BACKGROUND: Pancreaticoduodenectomy (PD) in dialysis patients is rare but carries a high risk of complications and mortality. This study aimed to identify preoperative factors associated with severe postoperative complications and mortality. METHODS: Using the Japanese National Clinical Database, 329 dialysis patients undergoing PD between 2016 and 2020 were retrospectively analyzed. Multivariable penalized logistic regression identified preoperative risk factors for Clavien-Dindo classification (CDC) grade ≥ 4 complications, 30-day mortality, operative mortality, postoperative sepsis, and postoperative pancreatic fistula (POPF) (grade B or C). RESULTS: CDC grade ≥ 4 complications, 30-day mortality, and operative mortality occurred in 10.3%, 5.5%, and 11.2%, respectively. Diet- or oral medication-treated diabetes (Odds ratio 5.19, 95% confidence interval 1.19-22.66) and insulin-treated diabetes (7.50, 1.61-34.93) independently predicted 30-day mortality. Serum albumin levels < 3.0 g/dL independently predicted operative mortality (2.72, 1.05-7.02), while cardiovascular disease showed a borderline association (2.15, 0.95-4.85). Elevated CRP was significantly associated with postoperative sepsis (2.47, 1.07-5.67), and pancreatic cancer was associated with a lower risk of POPF (grade B or C) (0.59, 0.37-0.94). CONCLUSIONS: Dialysis patients undergoing PD face perioperative risks. Early mortality is driven by acute metabolic and infectious vulnerability, whereas operative mortality reflects diminished physiologic reserve related to malnutrition and cardiovascular comorbidity.

OBJECTIVE: To describe real-world disease-free survival (DFS) and overall survival (OS) after radical cystectomy (RC) for muscle-invasive bladder cancer (MIBC) in Japan using nationwide data from the National Clinical Database (NCD). METHODS: This nationwide descriptive study included patients with MIBC who underwent RC and were registered in the NCD in 2020. Demographic and clinical characteristics, including age, sex, surgical approach, neoadjuvant chemotherapy (NAC), and pathological stage, were summarized. DFS and OS were estimated using the Kaplan-Meier method. Survival outcomes were descriptively compared across age groups, sex, NAC status, and surgical approach without adjustment for baseline characteristics. RESULTS: A total of 3773 patients were analyzed. The cohort showed an advanced age distribution, with 41% aged ≥ 75 years. Robotic-assisted RC was the most frequently performed approach (44%), and NAC was administered in 52% of patients. Survival declined progressively with increasing age, with the poorest outcomes observed in patients aged ≥ 80 years. Female sex and nonreceipt of NAC were associated with modestly lower DFS and OS in unadjusted analyses. Robotic-assisted and laparoscopic RC demonstrated comparable DFS and OS, whereas open RC was associated with less favorable survival outcomes. CONCLUSIONS: This nationwide descriptive analysis provides a comprehensive snapshot of real-world survival after RC for MIBC in Japan. This nationwide data reveal marked heterogeneity in patient characteristics, treatment patterns, and outcomes, and provide a foundation for identifying clinically relevant hypotheses for future risk-adjusted analyses.

PURPOSE: To provide a nationwide overview of groin hernia surgeries in Japan, using data from the National Clinical Database (NCD) as of 2023, with emphasis on procedure types, demographic trends, and hernia classification by sex and recurrence status. METHODS: We analyzed data on groin hernia surgeries registered in the NCD from January to December, 2023. Procedures were classified into four categories: open or endoscopic, and inguinal or femoral. Variables included age, sex, surgical urgency, anesthesiologist involvement, and admission type. Longitudinal trends (2011–2023) and sex-/recurrence-specific differences were also evaluated. RESULTS: A total of 127,139 groin hernia repairs were performed at 2,143 institutions. Inguinal hernias accounted for 96.5% of the repairs and femoral hernias accounted for 3.5%, with 56.8% of all the hernias repaired endoscopically. Emergency surgery was done more frequently for femoral hernias (44.3%) than for inguinal hernias (2.6%). Femoral hernias were more common in women, and their proportion was higher among recurrent hernias than primary hernias for both sexes. Recurrent hernia repair comprised 3.8% of the hernia surgeries for male patients and 1.9% of those for female patients. The number of endoscopic repairs increased over time, especially for bilateral hernias. CONCLUSION: This is the first large-scale hernia classification study from Asia. It highlights sex- and recurrence-specific patterns and supports clinical and international registry comparisons.

<h4>Background</h4>This study assessed the impact of an institutional certification system that was newly introduced by the Japanese Gastric Cancer Association on short-term surgical outcomes in patients with gastric cancer using data from the National Clinical Database.<h4>Methods</h4>A retrospective cohort study of distal gastrectomy and total gastrectomy procedures performed between January 2020 and December 2022 was conducted. The institutions were classified into three categories: type A, type B, and non-certified institutions, in decreasing order of certification stringency. The primary outcome was the incidence of grade ≥ IIIa postoperative complications based on the Clavien-Dindo classification system. The secondary outcome was surgery-related mortality. Logistic regression with risk adjustment, estimated using generalized estimating equations, was used to account for intra-cluster correlation.<h4>Results</h4>There was no significant difference in the risks of distal gastrectomy-related complications across the three institution types. However, type A- (odds ratio (OR) 0.39, 95% confidence interval (CI) 0.31-0.49) and type B-certified institutions (OR 0.59, 95% CI 0.49-0.71) had a significantly lower mortality risk than non-certified ones. On the other hand, Type A- (OR 1.25, 95% CI 1.09-1.44) and type B-certified institutions (OR 1.17, 95% CI 1.03-1.33) had higher risks of postoperative total gastrectomy-related complications than non-certified ones. Nevertheless, type A- (OR 0.41, 95% CI 0.29-0.58) and type B-certified institutions (OR 0.67, 95% CI 0.51-0.88) had significantly lower surgery-related mortality risks than non-certified ones.<h4>Conclusions</h4>Certified institutions demonstrated lower surgical mortality risks, highlighting the benefits of the certification system and the importance of institutional quality.

BACKGROUND: In Japan, the rapid reduction and aging of surgeons have become a serious problem in gastroenterological surgery field, therefore, an increase in the number and the activity of female surgeons is essential. Previous most studies comparing surgical outcomes between male and female surgeons included a variety of surgical procedures, which leads to be inconclusive. METHODS: This study enrolled patients who underwent laparoscopic right hemicolectomy for colon cancer and were registered in the Japanese National Clinical Database (NCD) between 2018 and 2022. A logistic model was applied to calculate the risk-adjusted odds ratio (OR) of surgical outcomes in comparison between male and female surgeons. Main outcome measures were surgical mortality and severe postoperative complications. RESULTS: Finally, 58 503 surgeries (male surgeon: 53 387 (91.3%), female surgeons: 5116 (8.7%)) were identified and analyzed. Female surgeons had fewer post-registration years and similar surgical risk patients compared with male surgeons. No significant differences were observed in the adjusted risk for mortality and severe complications between male and female surgeons (mortality: OR 1.29, 95% confidence interval (CI) 0.87-1.92 and severe complications: OR 0.96, 95% CI 0.83-1.13, respectively). CONCLUSIONS: From our results using NCD, no significant differences were observed in surgical mortality and severe complications in patients who underwent laparoscopic right hemicolectomy between male and female surgeons. Our findings suggest that providing well-structured and efficient surgical training programs for all surgeons, regardless of gender, may help further improve surgical quality.

BACKGROUND: Retroperitoneal tumors (RPTs) are rare and anatomically complex neoplasms, for which surgery remains the mainstay of treatment. However, real-world data on their surgical management in Japan have been limited. OBJECTIVE: To describe the clinical characteristics and short-term outcomes of patients undergoing resection for RPTs in Japan, based on data from gastroenterological surgical practice. METHODS: This study analyzed data from the Japanese National Clinical Database (NCD) for gastroenterological surgery. A total of 4948 patients with RPT who underwent surgery between 2019 and 2021 were included. RESULTS: There were 2360 men (47.7%) and 2588 women (52.3%), with a median age of 66 years. RPTs were histologically classified as malignant in 75.3% and benign in 24.7% of cases. The median operative time was 205 min, and the median blood loss was 150 mL. Postoperative complications occurred in 23.9% of patients, with 7.5% experiencing severe complications (Clavien-Dindo grade III or higher). The 30 day postoperative mortality rate was 0.5%, and the perioperative mortality rate was 1.0%. CONCLUSION: This analysis demonstrates that a substantial number (approximately 1650 per year) of RPTs surgeries are performed annually by gastrointestinal surgeons in Japan, and that the short-term surgical outcomes are acceptable. These data provide an important reference to exhibit the current surgical practice in Japan and to develop future strategies for RPTs.

BACKGROUND: Heat-not-burn cigarettes (HNBCs) are marketed as reduced-risk combustible cigarette alternatives. However, their impact on surgical outcomes after invasive procedures, including esophagectomy, remains unclear. To evaluate the association between preoperative HNBC use and short-term outcomes after oncological esophagectomy. METHODS: This retrospective cohort study utilized Japanese National Clinical Database data from patients who underwent esophagectomy for thoracic esophageal cancer between January 2019 and December 2021. The exposure was self-reported HNBC use within 1 year before surgery. The primary outcome was operative mortality. Secondary outcomes included life-threatening complications (Clavien-Dindo classification ≥ IV), anastomotic leakage, postoperative pneumonia, surgical site infection, and prolonged mechanical ventilation (≥ 48 h). Associations between HNBC use and outcomes were assessed using multilevel logistic regression models, adjusting for patient demographics, comorbidities, combustible cigarette smoking history, alcohol use, and tumor characteristics. RESULTS: Of 17,797 patients, 589 (3.3%) reported preoperative HNBC use. HNBC users were younger and male, with higher rates of concurrent combustible cigarette use (85.2% vs. 33.2%), intense smoking history (Brinkman index ≥ 600:67.2% vs. 47.9%), and habitual alcohol consumption (80.5% vs. 66.6%) than non-users. After adjusting for confounders, HNBC use was associated with nonsignificant trends toward increased operative mortality [adjusted odds ratio (aOR): 1.82, 95% confidence interval (CI): 0.95-3.48; P = 0.07] and life-threatening complications (aOR: 1.56, 95% CI: 0.98-2.48; P = 0.06). No other secondary outcomes were significantly associated with HNBC use. CONCLUSIONS: The observed trends, although nonsignificant, suggest that preoperative HNBC use may be associated with increased risks of operative mortality and life-threatening complications, warranting further investigation.

<jats:title>ABSTRACT</jats:title> <jats:sec> <jats:title>Aim</jats:title> <jats:p>The National Clinical Database (NCD) of Japan is the largest nationwide registry, covering over 95% of surgeries in the country. This 2022 annual report summarizes the short‐term outcomes of gastroenterological surgeries and discusses trends and insights over the past decade.</jats:p> </jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>We analyzed the NCD data for gastroenterological surgeries performed between 2013 and 2022. The number of surgeries, patient demographics, surgical approaches, postoperative outcomes, and the involvement of board‐certified surgeons and anesthesiologists were examined.</jats:p> </jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>A total of 591 221 surgeries were recorded in 2022. Compared to 2021, the overall surgical volume remained stable, with a continued increase in minimally invasive procedures. Patient aging continued across all organ categories, with a rise in the proportion of patients aged ≥ 80 years. Board‐certified surgeon participation remained high in complex procedures, while emergency surgeries were associated with higher morbidity and mortality. Operative mortality continued to decrease, particularly in pancreatic and hepatic surgeries.</jats:p> </jats:sec> <jats:sec> <jats:title>Conclusion</jats:title> <jats:p>The 2022 NCD data provide a comprehensive overview of the current status and evolving trends in gastroenterological surgery in Japan. Continued efforts toward data‐driven quality improvement and surgical education remain essential.</jats:p> </jats:sec>

<jats:title>ABSTRACT</jats:title> <jats:sec> <jats:title>Aim</jats:title> <jats:p>The adoption of robot‐assisted surgery (RAS) in Japan has progressed significantly since its initial approval in 2009. RAS gradually expanded into various surgical fields with 35 procedures now covered under Japan's national health insurance. This study provides an inaugural assessment of RAS outcomes for seven digestive procedures introduced in 2018.</jats:p> </jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>The Japanese Society for Endoscopic Surgery working group established an RAS registry integrating data from the National Clinical Database and additional RAS‐specific records. The analysis focused on three major gastrointestinal fields: the esophagus, stomach, and rectum.</jats:p> </jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>In 2019, 530 esophagectomies, 2295 gastrectomies, and 3269 proctectomies were performed. RAS for these procedures was characterized by relatively long operative times, low intraoperative blood loss, and very low conversion rates to open surgery (&lt; 1%). Postoperative morbidity rates Grade IIIa or higher were 23.2% for esophagectomy, 4.9% for gastrectomy, and 9.4% for proctectomy. Length of postoperative hospital stay correlated with morbidity, though readmission (1.3%–3.1%) and postoperative mortality rates (0.3%–0.6%) remained low. The early nationwide implementation of RAS in Japan was marked by a high surgeon qualification rate (98.9%) and meticulous case selection; the DVSS Xi model accounted for 66.3% of robotic platforms used.</jats:p> </jats:sec> <jats:sec> <jats:title>Conclusion</jats:title> <jats:p>These findings underscore the need for ongoing surveillance and data‐driven evaluation to ensure safe and effective implementation of RAS. Future longitudinal analyses will refine surgical quality, optimize resource allocation, and advance minimally invasive techniques. This study highlights the transformative potential of RAS in Japanese surgical practice and its alignment with global trends.</jats:p> </jats:sec>

<jats:title>ABSTRACT</jats:title><jats:sec><jats:title>Background</jats:title><jats:p>Radical gastrectomy with lymph node dissection is the primary treatment for gastric cancer. However, the overall complication rate remains approximately 10%–20%, with a postoperative mortality rate of 2.3%. Therefore, preoperative stratification of patients based on their expected surgical risks is important. This study aimed to develop a deep learning prediction model using big data from the National Clinical Database (NCD) to predict operative mortality after total gastrectomy.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>Patients aged 18 years or older who underwent total gastrectomy for gastric cancer and were registered in the NCD between January 2018 and December 2019 were included. A total of 62 variables, including age, sex, past medical history, preoperative blood test results, and tumor characteristics, were used as covariates, with operative mortality as the outcome variable. Deep learning models were developed using Python, TensorFlow and Keras. Hyperparameters were adjusted using the k‐fold method with the training data. The model was evaluated using validation data.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Of the 14 980 eligible cases, 11 980 were used for training and 3000 for validation. The event rate was 1.2%. A four‐layer, 5217‐variable model was developed. The final C‐statistic was 0.79 (95% confidence intervals: 0.74–0.83) for the training data and 0.74 (95% confidence intervals: 0.62–0.85) for the validation data.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>We developed a deep learning model to predict operative mortality using big data from the NCD. To improve the accuracy, it is necessary to introduce new variables related to postoperative complications or factors that cannot be analyzed using conventional methods.</jats:p></jats:sec>

<jats:title>ABSTRACT</jats:title> <jats:p>Accurate prediction of postoperative complications is critical in surgical care. Recently, deep learning has gained attention and has been applied to various predictive models and image recognition tasks, and researchers are attempting to apply this technology in medicine. This review compares logistic regression, machine learning, and deep learning models used in gastroenterological surgery. There are some studies reporting predictive models with large databases. Among these studies, some studies showed that deep learning outperformed other models, but others reported random forests or gradient boosting methods, a type of machine learning, performed better than the other methods including deep learning. On the other hand, applying image or time‐series data are reported to increase the prediction accuracy of postoperative morbidity/mortality, despite relatively small sample sizes. While deep learning shows potential, especially with image and time‐series data, it often underperforms on tabular clinical datasets such as current National Clinical Database (NCD). We discuss the limitations of deep learning in term of its “black‐box” nature and highlight the need for integrating complex data types to improve model accuracy and interpretability. Incorporating multimodal inputs may enable deep learning to outperform conventional methods and better support clinical decision‐making.</jats:p>

PURPOSE: To identify the risk factors for mortality and morbidity after distal pancreatectomy with en bloc celiac axis resection (DP-CAR) using prospectively registered data from the National Clinical Database (NCD). METHODS: We retrospectively analyzed patients registered in the NCD between 2018 and 2021 who underwent DP-CAR. Surgical morbidity, mortality, and associated clinical factors were evaluated. RESULTS: The study included 136 patients. Preoperative therapy included chemotherapy in 110 (80.9%) patients. The surgical mortality rate was 2.2% (3/136 patients). Recent weight loss (≥ 10% in the past 6 months) was significantly more prevalent in the mortality group than in the non-mortality group (33.3% [1/3] vs. 4.5% [6/133], respectively). Clavien-Dindo grade ≥ III complications occurred in 34.6% of the patients. Age ≥ 80 years old (odds ratio [OR], 8.75; 95% confidence interval [CI]: 1.21-63.43; p = 0.032) and portal vein resection (OR, 2.72; 95% CI: 1.04-7.13; p = 0.042) were identified as potential risk factors for severe postoperative complications. Recent weight loss (OR, 5.18; 95% CI: 0.96-27.8; p = 0.055) approached statistical significance. CONCLUSION: Although specific mortality risk factors could not be identified, the low mortality rate suggests that DP-CAR is safely performed in Japanese practice. Future efforts should focus on achieving zero DP-CAR-associated mortality.

PURPOSE: Endocrine surgery encompasses various organ systems, but thyroid surgery represents the major component. The Japanese Association of Thyroid Surgeons published nationwide data on thyroid cancer surgery until 2005, since when no further reports have been published. Thus, we analyzed thyroid surgery trends using data from the National Clinical Database (NCD) from 2014 to 2023. METHODS: We analyzed cases of thyroid surgery, for malignant and benign conditions, recorded in the NCD. A detailed analysis of papillary thyroid carcinoma (PTC) cases was conducted in 2014, 2019, and 2023 to assess TNM classification, surgical procedures, complications, and outcomes. RESULTS: The number of thyroid surgery facilities and the number of thyroid surgeries being performed have both declined since 2020. A trend toward more hemithyroidectomies and fewer total thyroidectomies for PTC is evident. The number of surgeries for cancers < 1 cm and lateral node dissection for PTC have also decreased. Endoscopically assisted surgery has increased continuously, accounting for > 4% of thyroid operations in 2020. The incidence of permanent hypoparathyroidism has decreased and perioperative mortality is rare. CONCLUSION: The changes in surgical trends are aligned with guideline updates and shifts in surgical practice. Future efforts will refine data collection and utilize the NCD to improve thyroid surgical quality and research.

BACKGROUND: Minimally invasive surgery (MIS) is increasingly used for gastric cancer; however, its application to remnant gastric cancer (RGC) remains technically challenging due to adhesions and altered anatomy. Large-scale comparative data on the safety and effectiveness of MIS versus open surgery for RGC are limited. This retrospective study aimed to evaluate the short-term outcomes of MIS versus open completion total gastrectomy for RGC. METHODS: We retrospectively analyzed data from 3337 patients who underwent completion total gastrectomy for RGC between January 2018 and December 2022 using the National Clinical Database of Japan. After applying predefined inclusion criteria, we performed one-to-one propensity score matching to balance baseline characteristics between the MIS and open surgery groups and compared short-term surgical outcomes. RESULTS: After matching, 540 patient pairs were included in the analysis. MIS was associated with a significantly longer operative time (median 344 vs. 248.5 min; P < 0.001) but reduced blood loss (median 70 vs. 290 mL; P < 0.001). The incidence of anastomotic leakage was higher in the MIS group (9.8% vs. 6.3%; P = 0.034). Postoperative hospital stay was numerically shorter in the MIS group (median 13 vs. 14 days; P = 0.065). Overall complication, reoperation, and mortality rates were comparable between groups. CONCLUSIONS: MIS for RGC showed comparable short-term outcomes to those of open surgery in a nationwide analysis, with advantages including reduced blood loss. However, the increased risk of anastomotic leakage highlights the need for careful patient selection and ongoing technical refinement.

AIM: To investigate the role of witnessed arrest as an effect modifier on neurological outcomes following bystander cardiopulmonary resuscitation (CPR) in patients with out-of-hospital cardiac arrest (OHCA). METHODS: This cohort study was conducted using an OHCA patient registry collected between September 2019 and March 2021 in Japan. The effect modification by witnessed arrest was analyzed using additive and multiplicative interactions with risk adjustment. The main outcome was a cerebral performance category of 1 or 2 at 30 days after OHCA. RESULTS: A total of 7496 patients from 42 hospitals were analyzed. Witnessed arrest and bystander CPR occurred in 3053 (40.7 %) and 3152 (42.0 %) patients, respectively. The adjusted odds ratio (OR) of witnessed arrest and bystander CPR for favorable neurological outcomes was 11.36 (95 % confidence interval [CI]: 7.10-18.17). The ORs for bystander CPR within each stratum of witnessed arrest were 2.38 (95 % CI: 1.34-4.24) for non-witnessed arrest and 3.80 (95 % CI: 2.61-5.55) for witnessed arrest. The additive interaction was 7.01 (95 % CI: 3.34-10.68) and the multiplicative interaction was 1.60 (95 % CI: 0.80-3.17). In the non-home arrest setting, bystander CPR had an adjusted OR of 1.23 (95 % CI: 0.58-2.62) for non-witnessed arrest and 2.77 (95 % CI: 1.69-4.53) for witnessed arrest. The additive interaction was 4.98 (95 % CI: 1.67-8.29) and the multiplicative interaction was 2.25 (95 % CI: 0.91-5.53). CONCLUSIONS: The interaction effect of bystander CPR and witnessed arrest exhibited the second strongest form of interaction. The non-significant effect of bystander CPR in non-witnessed arrest in the non-home cardiac arrest setting warrants further investigation.

<jats:title>ABSTRACT</jats:title><jats:sec><jats:title>Background</jats:title><jats:p>Excess intraoperative fluid can increase postoperative complications in elective surgery, but data on esophageal cancer surgery remain limited. We examined the relationship between intraoperative fluid volume and short‐term outcomes after minimally invasive esophagectomy.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>This study analyzed 8782 patients who underwent minimally invasive esophagectomy between 2018 and 2022 using data from the National Clinical Database in Japan. Multivariable logistic regression and smoothing spline models were used to assess associations between intraoperative fluid volume and short‐term outcomes.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>The median intraoperative fluid volume was 3700 mL (3000–4500) or 7.8 mL/kg/h (6.2–9.7). Postoperatively, pneumonia occurred in 13.6% of patients, anastomotic leakage in 13.1%, prolonged ventilation (&gt; 48 h) in 3.5%, and surgery‐related mortality in 0.8%. Patients were classified into tertiles (low, middle, high) based on fluid volume. A high intraoperative fluid volume was significantly associated with pneumonia (risk‐adjusted odds ratio 1.22, 95% confidence interval 1.04–1.45, <jats:italic>p</jats:italic> = 0.02). However, there was no significant association with anastomotic leakage, prolonged ventilation, or surgery‐related mortality. Smoothing spline model showed a positive monotonic relationship between fluid volume and the risk‐adjusted odds ratio for pneumonia, prolonged ventilation, and surgery‐related mortality, whereas anastomotic leakage showed a negative monotonic trend.</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>Higher intraoperative fluid volume was significantly associated with an increased risk of pneumonia after minimally invasive esophagectomy.</jats:p></jats:sec>

<jats:title>ABSTRACT</jats:title><jats:sec><jats:title>Aim</jats:title><jats:p>Previous studies have shown that the volume and short‐term outcomes of advanced hepatectomy in Japan remained stable during the coronavirus disease 2019 (COVID‐19) pandemic. However, whether these trends have changed in the postpandemic period remains unclear. This study aimed to evaluate surgical volume and short‐term outcomes following advanced hepatectomy in Japan during the postpandemic era.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>Data from the Japanese National Clinical Database (NCD) were analyzed for patients who underwent advanced hepatectomy between 2018 and 2023. Changes in the number of the procedures, major complications (Clavien–Dindo grade ≥ III), 30‐day and inhospital mortality rates, and failure‐to‐rescue rates were assessed. The standardized morbidity and mortality ratios—calculated as the observed‐to‐expected incidence rates using an NCD‐established risk model for 30‐day mortality, inhospital mortality, and major complications—were also examined.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>A total of 39 348 cases were included. The number of advanced hepatectomies showed a gradual decline, independent of the COVID‐19 pandemic. However, the proportion of patients aged over 80 years significantly increased throughout the study period. Monthly standardized mortality and morbidity ratios largely remained stable across the study period, including during the pandemic and postpandemic eras.</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>Analysis of data from a nationwide Japanese database indicates that advanced hepatectomy continues to be performed safely in the post‐COVID‐19 era, despite a decreasing procedural volume.</jats:p></jats:sec>

INTRODUCTION: The COVID-19 pandemic has disrupted elective surgeries worldwide. This study evaluated the impact of the pandemic on thoracic surgery volumes in Japan and investigated real-world triage practices by thoracic surgeons. METHODS: Using Japan's National Clinical Database, we analyzed both annual and quarterly trends in surgical procedures and patient characteristics of lung and thymic tumors from 2019 to 2023. RESULTS: Compared to 2019, surgeries for primary lung cancer, thymic tumors, and spontaneous pneumothorax declined in 2020, with the most pronounced decreases occurring in Q2 during Japan's first state of emergency. Specifically, the numbers declined by 8.7%, 9.7%, and 27.1%, respectively. The greatest decline in pathological (p-) stage 0-IA1 lung cancer cases occurred in Q2 2020 (- 22% vs. Q2 2019), while reductions in more advanced stages during Q2 remained below 10%, with peak decreases observed in Q3. By 2023, the number of p-Stage II-IV cases had decreased, while the number of IA1-IB cases had increased. Thymoma and thymic cysts declined in Q2 2020 (- 4.4%, - 35.1%, respectively), but thymic cancer remained stable. Notably, thymic tumor size showed no temporal change throughout the study period. DISCUSSION: Despite strategic triage by thoracic surgeons during the initial phase of the pandemic, the overall disease profile of thoracic malignancies remained largely unaffected by treatment delays through 2023 in Japan. (200 words).

BACKGROUND: The association between preoperative liver function and short-term outcomes after gastrointestinal cancer surgery is unknown. This study investigated the impact of Child-Pugh score-based preoperative liver dysfunction on short-term outcomes after distal gastrectomy and right hemicolectomy. MATERIALS AND METHODS: We included patients who underwent distal gastrectomy for gastric cancer or right hemicolectomy for colon cancer between 2018 and 2022 from the Japanese National Clinical Database. Patients were classified based on their Child-Pugh scores, and the association between Child-Pugh scores and short-term outcomes was assessed using multivariable logistic regression. Overall postoperative mortality and incidence of postoperative complications within 30 days (Clavien-Dindo Grade >III) were evaluated. RESULTS: A total of 104,905 distal gastrectomy and 62,775 right hemicolectomy cases were included. Overall surgery-related mortality increased to 31.8% and 20.7% and overall complication rate increased to 18.2% and 31% in patients with a Child-Pugh score of 9 who underwent distal gastrectomy and right hemicolectomy, respectively. Even after risk adjustment, those with a score of 9 had a significantly higher risk of surgical mortality than patients with a Child-Pugh score of 5 following distal gastrectomy (OR 64.80, 95% CI 23.64-177.65) and right hemicolectomy (OR 39.56, 95% CI 14.77-106.01). CONCLUSIONS: Surgical mortality and incidence of surgical complications were associated with the Child-Pugh score in a score-dependent manner. The Child-Pugh score effectively estimates postoperative risk in gastrointestinal cancer surgery. Special caution is needed for patients with poor liver function, especially those with higher Child-Pugh scores.

<jats:title>ABSTRACT</jats:title><jats:sec><jats:title>Aim</jats:title><jats:p>This study evaluated the short‐term outcomes of low anterior resection for rectal cancer in Japan before and after the COVID‐19 pandemic, with a particular focus on the timing of its reclassification within Japan in May 2023.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>Using data from the Japanese National Clinical Database, we analyzed 109 754 low anterior resection cases between January 2018 and December 2023, categorized into pre‐pandemic (February 2020 and earlier), pandemic (March 2020–April 2023), and post‐pandemic (May 2023 onward) periods. Trends in the number of low anterior resection cases, postoperative intensive care unit utilization, and complications, including anastomotic leakage and pneumonia, were examined. Standardized morbidity ratios were used to adjust for risk and assess trends over time.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>The number of low anterior resection cases declined during the pandemic but returned to pre‐pandemic levels thereafter. The postoperative intensive care unit admission rates remained stable, with a slight increase post‐pandemic. The incidence of major complications gradually declined from pre‐pandemic to post‐pandemic, with anastomotic leakage rates decreasing from 9.8% to 7.1% and the standardized morbidity ratio for anastomotic leakage decreasing from 1.0 to 0.8, reflecting improved outcomes. The number of robot‐assisted surgeries significantly increased from 246 cases in March 2020 to 535 in May 2023, and their proportion among total surgeries also rose from 16.8% to 41.2%.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>Despite initial challenges, the healthcare system of Japan effectively managed rectal cancer surgeries during and after the pandemic. Robotic surgery became more widely adopted, and complication rates improved, demonstrating resilience and adaptability in surgical care.</jats:p></jats:sec>

<jats:title>ABSTRACT</jats:title><jats:sec><jats:title>Background</jats:title><jats:p>We previously reported the gender disparities in surgical procedures between male and female surgeons using National Clinical Database covering more than 95% of all operations performed in Japan. This study aims to examine the changes in gender disparity in the surgical experience of gastrointestinal surgeons in Japan before and after implementation of measures by the Japanese Society of Gastrointestinal Surgery to address gender inequality commenced in 2021.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>We conducted a nationwide retrospective study to compare the number of operations performed by male and female surgeons using National Clinical Database. The number of operations per surgeon was calculated based on every 2 years of a surgeon's experience, and a comparison was made between male and female surgeons. The years selected for analysis were 2015, 2019, and 2023.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Almost no gender differences were observed in the number of low‐difficulty surgeries. For medium‐difficulty surgeries, the number performed by female surgeons showed an improving trend over the study period, yet some disparities remained. The number of high‐difficulty surgeries (low anterior resection and pancreaticoduodenectomy) performed by male surgeons was higher than the number performed by female surgeons, except for protrusions. This disparity remained unchanged over the study period.</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>The efforts of the Japanese Society of Gastrointestinal Surgery has been shown to be effective in mitigating gender disparities in the number of surgeries performed. High‐difficulty surgeries have emerged as the primary target for further improvement initiatives.</jats:p></jats:sec>

Predicting anastomotic leak preoperatively in patients undergoing low anterior resection for rectal cancer remains a significant challenge. This study aims to develop and validate a predictive model for anastomotic leaks using a machine learning algorithm. Data were collected on patients who underwent low anterior resection from 2015 to 2021 from the National Clinical Database in Japan. The patients were divided into 2 cohorts: a derivation cohort and a validation cohort. The derivation cohort included patients who underwent surgery between January 2015 and December 2019, while the validation cohort included those from January 2020 to December 2021. Three models were developed: logistic regression, logistic regression with least absolute shrinkage and selection operator (Lasso regression), and eXtreme gradient boosting model. We calculated the area under the receiver operating characteristic curve (AUROC) and compared it with the logistic regression model using the DeLong test. A total of 119,818 eligible patients were identified. The incidence of anastomotic leaks was 9.6% in the derivation cohort and 8.4% in the validation cohort, respectively. The predictive ability for the validation cohort using logistic regression (AUROC 0.6324, 95% confidence interval [CI] 0.6220-0.6427, reference) was similar to that of Lasso regression (AUROC 0.6333, 95% CI 0.6229-0.6436, P = .13) and eXtreme gradient boosting (AUROC 0.6333, 95% CI 0.6230-0.6437, P = .41). Machine learning prediction model for anastomotic leak using preoperative information routinely inputted in the National Clinical Database, showed suboptimal prediction ability. It wound be possible to share the fact with patients that preoperative prediction of anastomotic leak is difficult.

BACKGROUND: Radical cystectomy (RC) is a standard-of-care treatment for muscle-invasive bladder cancer (MIBC). However, there is a lack of data comparing the benefit of robot-assisted radical cystectomy (RARC) with laparoscopic radical cystectomy (LRC) or open radical cystectomy (ORC) in Japan. We aimed to explore the safety of RARC compared with that of LRC or ORC using the Japanese National Clinical Database (NCD). METHODS: This retrospective study reviewed the data of 17,549 patients with MIBC who underwent radical cystectomy between February 2019 and December 2022 in the Japanese NCD. We compared the postoperative complications within 30 days between the surgical procedures using the Clavien-Dindo classification. Multivariable logistic regression analysis was conducted for grade ≥ 3 postoperative complications. RESULTS: Overall, 8308, 3101, and 6140 patients underwent RARC, LRC, and ORC, respectively. The rates of any grade and grade ≥ 3 postoperative complications within 30 days were significantly lower in the RARC group than in the ORC group. RARC had no significant difference in grade ≥ 3 postoperative complications in the ileal neobladder. Regarding any grade postoperative complications, RARC had a significantly lower rate of delirium, surgical site infection, sepsis, and gastrointestinal tract leakage than ORC. Multivariable logistic regression analysis revealed that the incidence of grade ≥ 3 postoperative complications was significantly lower in RARC (odds ratio, 0.83; 95% confidence interval, 0.72-0.95). CONCLUSIONS: RARC had a lower complication rate compared with ORC. LRC had comparable outcomes to RARC. The findings of this study contribute to RARC as being the standard treatment for MIBC.

<jats:title>Abstract</jats:title> <jats:sec> <jats:title>Background</jats:title> <jats:p>The registration committee for esophageal cancer in the Japan Esophageal Society (JES) has collected the characteristics, treatments, and outcomes of patients who underwent any treatment in 2016 in Japan.</jats:p> </jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>We analyzed data on patients who had visited the participating hospitals in 2016. We collected the data using the National Clinical Database with a web-based data collection system. We used the Japanese Classification of Esophageal Cancer 11th edition by JES and the TNM Classification 8th edition by the Union of International Cancer Control (UICC) for cancer staging. Two committee members (A. O. and M. T.), endorsed by the Japan Esophageal Society and certified by the NCD, analyzed the data.</jats:p> </jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>A total of 9,593 cases were registered from 347 institutions in Japan. Squamous cell carcinoma (SCC) and adenocarcinoma accounted for 87.5% and 7.2%, respectively. The 5-year survival rates of patients treated by endoscopic resection, concurrent chemoradiotherapy, radiotherapy alone, and esophagectomy were 89%, 36%, 26%, and 59%, respectively. Esophagectomy was performed in 4,988 cases. Minimally invasive approaches were selected for 65.1%, and 57.7% underwent thoracoscopic esophagectomy. The 5-year survival rates of esophagectomy cases with pStage 0, I, II, III, IVa, and IVb in the JES system were 83%, 79%, 67%, 40%, 34%, and 27%, respectively. In the UICC system, the survival of surgically resected SCC cases with pStage IVB, mainly due to supraclavicular lymph-node metastasis, was better than that with pStage IVA.</jats:p> </jats:sec> <jats:sec> <jats:title>Conclusion</jats:title> <jats:p>We hope that this report improves all aspects of diagnosing and treating esophageal cancer in Japan.</jats:p> </jats:sec>

<jats:title>ABSTRACT</jats:title><jats:sec><jats:title>Background</jats:title><jats:p>Frailty is a significant predictor of death in patients with atrial fibrillation (AF), with the frailty index (FI) acting as an effective severity classification tool. However, even in patients with a similar FI, the underlying clinical profiles can differ substantially. As the severity classification relies solely on the number of deficits without considering their interaction, distinct clinical subgroups with differing prognoses and care needs may remain unrecognized within the same frailty category. We aimed to identify novel phenotypes based on the deficit patterns in older AF patients.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>Using data from a comprehensive claims database in Shizuoka (2012–2018), we extracted patients aged ≥ 65 years with AF and frailty who initiated oral anticoagulants. Latent class analysis (LCA) was conducted for each frailty status using 34 variables incorporated in the electronic FI (eFI), which is determined through a coding‐based algorithm. We performed multivariable Cox proportional hazards to evaluate the associations between the latent classes and all‐cause death within each frailty status.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Among 11 533 patients (mean age: 79.3 ± 8.03 years; women: <jats:italic>N</jats:italic> = 5359 [46.5%]) categorized as mildly (eFI &gt; 0.12–0.24; <jats:italic>N</jats:italic> = 3967), moderately (&gt; 0.24–0.36; <jats:italic>N</jats:italic> = 4385) and severely frail (&gt; 0.36–0.60; <jats:italic>N</jats:italic> = 3181), LCA identified three to four classes within each category: mildly frail, Class 1: high prevalence of hypotension (<jats:italic>N</jats:italic> = 326), Class 2: high prevalence of heart failure (<jats:italic>N</jats:italic> = 1404), Class 3: high prevalence of polypharmacy (<jats:italic>N</jats:italic> = 2237); moderately frail, Class 1: high prevalence of hypotension (<jats:italic>N</jats:italic> = 966), Class 2: high prevalence of heart failure (<jats:italic>N</jats:italic> = 1521), Class 3: high prevalence of polypharmacy (<jats:italic>N</jats:italic> = 1598), Class 4: high prevalence of mobility problems (<jats:italic>N</jats:italic> = 300); and severely frail, Class 1: high prevalence of hypotension (<jats:italic>N</jats:italic> = 1378), Class 2: high prevalence of heart failure (<jats:italic>N</jats:italic> = 1198), Class 3: high prevalence of mobility problems (<jats:italic>N</jats:italic> = 605). After multivariable adjustment, the other classes exhibited lower mortality risks than in the class characterized by high prevalence of mobility problems in the moderately (HR [95% CI]; Class 1: 0.59 [0.45–0.79], <jats:italic>p</jats:italic> &lt; 0.001; Class 2: 0.71 [0.55–0.93], <jats:italic>p</jats:italic> = 0.013; Class 3: 0.68 [0.52–0.88], <jats:italic>p</jats:italic> = 0.003) and severely frail (Class 1: 0.89 [0.74–1.07], <jats:italic>p</jats:italic> = 0.22; Class 2: 0.77 [0.63–0.94], <jats:italic>p</jats:italic> = 0.010), whereas there was no difference among the classes in the mildly frail (Class 1 vs. Class 3: 0.97 [0.67–1.40], <jats:italic>p</jats:italic> = 0.86; Class 2 vs. Class 3, 0.94 [0.76–1.16], <jats:italic>p</jats:italic> = 0.57).</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>The LCA, focused on the deficit patterns incorporated in the eFI, identified phenotypes, each representing distinct clinical outcomes. The classification expands the utility of eFI in clinical practice.</jats:p></jats:sec>

BACKGROUND: The Japanese Society of Hepatobiliary and Pancreatic Surgery has established a certification system for experienced surgeons. Evaluating its efficacy requires accounting for patient risk variations. The National Clinical Database (NCD) facilitates this using risk-adjusted outcome measures to validate and compare surgical performance. METHODS: We analyzed the NCD from 2014 to 2020 to examine trends in adjusted odds ratios (AORs) for mortality and morbidity following pancreaticoduodenectomy using 2014 as the reference. Primary outcomes were surgical and 30-day postoperative mortality. Secondary outcomes included severe complications and grade C pancreatic fistula. Subgroup analyses considered surgeon and institutional certification. RESULTS: Analysis of 78 972 pancreaticoduodenectomy reports revealed a decrease in the AOR for surgical mortality from 0.906 (95% Confidence Interval [CI]: 0.759-1.082, p = 0.276) in 2015 to 0.647 (95% CI: 0.539-0.777, p < 0.001) in 2020. A significant downward trend in the incidence of Grade C pancreatic fistula was observed. Board-certified surgeons have demonstrated superior performance compared to nonboard-certified surgeons since 2014, with board-certified training institutions having significantly lower AORs than those without certification. The AOR for surgical mortality showed an annual decrease across institutions. CONCLUSIONS: The certification system for hepatobiliary-pancreatic surgery and participation in the NCD significantly decreased surgical mortality after pancreaticoduodenectomy.

BACKGROUND: There is no comprehensive report regarding which patient groups were disrupted by the COVID-19 pandemic in Japan having universal health insurance system. To provide the guidance regarding how to act in future pandemics, we investigated the changes in breast cancer (BC) diagnosis and treatment during the COVID-19 pandemic. METHODS: The trends of monthly data were calculated in relation to the variables of a total of 291,018 primary BCs registered on the Japanese National Clinical Database between January 2018 and April 2021. RESULTS: An analysis of the nationwide data during the pandemic showed 9% decrease of newly identified BC compared with before the pandemic. The impact was more relevant in the 40-50, 51-60 and 61-70-years age groups (13%, 8% and 9% decrease, respectively). The most substantial reduction was noted in patients identified through screenings without symptoms with a 17% decrease. These effects were also apparent in cT1, cN0, cStage 0, and cStage I (11%, 9%, 8% and 11% decrease, respectively). In breast surgery procedures, there was a notable decrease in breast-conserving surgery (13%) as well as post-operative radiation therapy (11%). During this period, strategies using neoadjuvant endocrine therapy or chemotherapy were implemented to avoid treatment delays for especially Stage I patients (1.5 folds increase). CONCLUSIONS: We have identified the patient groups that are more vulnerable to the effects of the pandemic. The changes during the pandemic might provide the guidance regarding how to act in future emergencies to minimize disadvantages for BC patients.

PURPOSE: This study aimed to clarify the current treatment status for biliary tract cancers based on data from the National Clinical Database (NCD) in Japan. METHODS: Total 3895 cases of biliary tract cancers registered in the NCD during 2021 were included. We identified the rates of resection, R0 resection, postoperative complications, and incidences of lymph node metastasis for gallbladder carcinoma, perihilar cholangiocarcinoma, distal bile duct carcinoma, and ampullary carcinoma. RESULTS: The number of biliary tract cancers registered in the NCD during 2021 was 3895 (1775 in extrahepatic bile duct carcinoma, 1422 in gallbladder carcinoma, and 698 in ampullary carcinoma). In gallbladder carcinoma, the resection (89.59%) and R0 resection rates (87.99%) were favorable, and the complication rate (6.05%) was lower than that of others. However, the postoperative complication rate could be higher in T3-T4 cases and when extrahepatic bile duct resection was performed concomitantly. Lymph node metastasis was frequently seen in 12.60% at the No. 13a lymph node. In perihilar cholangiocarcinoma, the R0 resection (69.82%) and complication rates (16.75%) were significantly lower and higher, respectively. In distal cholangiocarcinoma and ampullary carcinoma, metastasis was observed in approximately 2% and 10% of the dissected No. 16b1 para-aortic lymph nodes, respectively. In conclusion, although short-term surgical outcomes for biliary tract cancers in Japan might be acceptable, the significantly lower R0 resection and higher complication rates of perihilar cholangiocarcinomas indicate additional challenges for surgeons in the future and should continue to be monitored by the Japanese Society of Hepatobiliary and Pancreatic Surgery.

<jats:title>Abstract</jats:title><jats:sec><jats:title>Aim</jats:title><jats:p>To evaluate the impact of the coronavirus disease (COVID‐19) pandemic on short‐term outcomes of low anterior resection (LAR) across hospitals classified by surgical volume.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>Data of patients who underwent elective LAR for rectal cancer between 2018 and 2022 were obtained from the National Clinical Database of Japan. Hospitals were categorized into high‐, medium‐, and low‐volume groups. Each group was constituted to represent approximately one‐third of all surgeries performed between 2018 and 2019. The standardized morbidity/mortality ratios (SMRs) of Clavien–Dindo grade ≥3 (CD ≥ 3) complications were the primary endpoint. The secondary endpoints included anastomotic leakage, pneumonia, and surgical mortality.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>This study analyzed 91 800 cases of elective LAR, with 10.5% experiencing CD ≥ 3 complications, 8.8% anastomotic leakage, 0.9% pneumonia, and 0.5% surgical mortality. Despite COVID‐19, SMRs of CD ≥ 3 complications decreased from 2018 to 2022 across all groups. However, increases in the rates and SMRs of CD ≥ 3 complications were observed in low‐volume hospitals around mid‐2020, followed by a decline. Anastomotic leakage showed similar trends. The rates and SMRs of pneumonia and surgical mortality remained unchanged. Notably, anastomotic leakage rates were 7.6%, 8.9%, and 10.0% in high‐, medium‐, and low‐volume hospitals, respectively, indicating superior outcomes in high‐volume hospitals.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>Early COVID‐19 waves may have disproportionately affected low‐volume hospitals. However, the decline in SMRs of CD ≥ 3 complications from 2018 to 2022 across all three groups suggests the robustness and resilience of surgical services for rectal cancer in Japan. The potential disparity in short‐term outcomes among hospitals is a new concern.</jats:p></jats:sec>

<jats:title>Abstract</jats:title><jats:sec><jats:title>Aims</jats:title><jats:p>We previously reported no change in surgical outcomes for laparoscopic distal gastrectomy (LDG) and laparoscopic low anterior resection (LLAR) early in the COVID‐19 pandemic (2020), although the number of elective surgeries decreased. In 2021, COVID‐19 spread further, with vaccination and other medical measures based on several medical societies' guidelines being initiated. Using the Japanese National Clinical Database (NCD), we added 2022 data to the 2018–2021 data to analyze the impacts of expansion of the COVID‐19 infection and its spread on laparoscopic surgery (including robot‐assisted surgery).</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>Data on patients who underwent LDG and LLAR for cancer were extracted from the NCD between 2018 and 2022. The numbers of LDG and LLAR were obtained, and morbidity and mortality rates were evaluated using a standardized morbidity/mortality ratio (SMR), i.e. the ratio of the observed number of incidences to expected number of incidences calculated by the risk calculator previously developed by the NCD.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>The numbers of LDG and LLAR cases declined in 2020, the first pandemic year, and continued to decline in 2022 to the same level as 2021, but with no further decline and no recovery trend in the number of cases. Numbers of robot‐assisted LDG and LLAR cases increased but at a rate lower than the prepandemic increase. Mortality and anastomotic leakage, two very important complications assessed in SMR, did not worsen during the pandemic compared to prepandemic levels.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>In Japan, laparoscopic surgery was safe and unaffected by the COVID‐19 pandemic, even in 2022, when the epidemic spread.</jats:p></jats:sec>

<jats:title>Abstract</jats:title><jats:sec><jats:title>Aim</jats:title><jats:p>Previous studies indicated that short‐term outcomes for gastroenterological surgeries did not worsen during the COVID‐19 pandemic. However, it remains unclear whether surgical volumes and medical resource use have recovered postpandemic. This study examines pre‐ and postpandemic trends in upper gastrointestinal surgeries, including esophagectomy and gastrectomy, and their short‐term outcomes.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>Data from the Japan's National Clinical Database (NCD) were analyzed for patients who underwent esophagectomy for esophageal cancer and gastrectomy for gastric cancer between January 2018 and December 2023. We evaluated changes in surgical volume, intensive care unit (ICU) use, morbidity, mortality rates, and the standardized morbidity and mortality ratio (SMR)—a comparison of observed versus expected outcomes using an NCD‐established risk calculator. Key metrics included 30d mortality, surgical mortality, and four major morbidities like pneumonia and anastomotic leakage.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Esophagectomy volumes remained stable from 2018 to 2023, while gastrectomy volumes decreased notably over the past 6 y. The proportion of patients over 70 increased significantly in both surgery types. Morbidity and mortality rates showed no significant deterioration postpandemic, as indicated by SMR values.</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>This study analyzed changes in surgical volume and short‐term outcomes for upper gastrointestinal cancer in the post‐COVID‐19 era using a Japanese nationwide database. It found that surgical treatments for gastrectomy and esophagectomy remained safe even after the pandemic.</jats:p></jats:sec>

<jats:title>Abstract</jats:title><jats:sec><jats:title>Aim</jats:title><jats:p>Risk prediction models for mortality, severe postoperative complications, and postoperative pancreatic fistula in patients undergoing pancreaticoduodenectomy were established using data from the National Clinical Database more than a decade ago, and the surgical outcomes of pancreaticoduodenectomy have improved over the years. The aim of this study is to update the risk prediction model for pancreaticoduodenectomy using National Clinical Database data.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>Between 2019 and 2021, the data of 35 365 patients who underwent pancreaticoduodenectomy and who were registered in the National Clinical Database were retrospectively analyzed. According to the registration year, the patients were divided into two cohorts: the development cohort (2019–2020; <jats:italic>n</jats:italic> = 23 654) and the validation cohort (2021; <jats:italic>n</jats:italic> = 11 711). Logistic regression analyses were performed to create risk models for surgical mortality, severe postoperative complications, and grade C postoperative pancreatic fistula.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Overall, the rates of surgical mortality, severe postoperative complications, and grade C postoperative pancreatic fistula were 1.8%, 2.2%, and 1.3%, respectively. Logistic regression analyses revealed 28, 28, and 14 risk factors for surgical mortality, severe postoperative complications, and grade C postoperative pancreatic fistula, respectively. The area under the receiver operating characteristic curve of the risk model in the development cohort was 0.759 for surgical mortality, 0.712 for severe complications, and 0.699 for postoperative pancreatic fistula, comparable to the validation cohort. The calibration plots were favorable in both cohorts.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>The updated risk model for pancreaticoduodenectomy will be useful to predict surgical mortality, severe postoperative complications, and grade C postoperative pancreatic fistula.</jats:p></jats:sec>

<jats:title>Abstract</jats:title><jats:sec><jats:title>Aim</jats:title><jats:p>Possible negative effects of the COVID‐19 pandemic on short‐term postoperative outcomes for colorectal perforation in Japan were examined in this study.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>The National Clinical Database (NCD) is a large‐scale database including more than 95% of surgical cases in Japan. We analyzed 13 107 cases of colorectal perforation from 2019 to 2021. National data were analyzed, and subgroup analyses were conducted for subjects in prefectures with high infection levels (HILs) and metropolitan areas (Tokyo Met. and Osaka Pref.). Postoperative 30‐day mortality, surgical mortality, and postoperative complications (Clavien–Dindo grade ≥3) were examined. Months were considered to have significantly high or low mortality or complication rates, if the 95% confidence interval (CI) of the standardized mortality (morbidity) ratio (SMR) does not contain 1.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>In the NCD, postoperative 30‐day mortality occurred in 1371 subjects (10.5%), surgical mortality in 1805 (13.8%), and postoperative complications in 3950 (30.1%). Significantly higher SMRs were found for 30‐day mortality in November 2020 (14.6%, 1.39 [95% CI: 1.04–1.83]) and February 2021 (14.6%, 1.48 [95% CI: 1.10–1.96]), and for postoperative complications in June 2020 (37.3%, 1.28 [95% CI: 1.08–1.52]) and November 2020 (36.4%, 1.21 [95% CI: 1.01–1.44]). The SMRs for surgical mortality were not significantly high in any month. In prefectures with HILs and large metropolitan areas, there were few months with significantly higher SMRs.</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>The COVID‐19 pandemic had limited negative effects on postoperative outcomes in patients with colorectal perforation. These findings suggest that the emergency system for colorectal perforation in Japan was generally maintained during the pandemic.</jats:p></jats:sec>

PURPOSE: This study aimed to investigate the effects of the coronavirus disease 2019 pandemic on morbidity and mortality after advanced hepatectomy by surgical volume in Japan. METHODS: Data from patients who underwent advanced hepatectomy between 2018 and 2022 from the Japanese National Clinical Database were collected. The transition of the number of hepatectomies and changes in risk-adjusted mortality and major complication rates based on the type of institutions certified by the Japan Society of Hepato-Biliary-Pancreatic Surgery were investigated. RESULTS: A total of 33 454 cases were included. The number of advanced hepatectomies gradually decreased, whereas the proportion of hepatectomies performed in certified institutions increased (from 63.4% in 2018 to 71.3% in 2022). Although the major complication rate in institution A was higher than that in institution B or noncertified institutions (16.3% vs. 14.5% vs. 13.5%), the in-hospital mortality rate was consistently favorable in the order of institution A, institution B, and noncertified institutions (1.4% vs. 2.0% vs. 2.8%). The monthly standardized mortality and major complication ratios did not significantly increase mostly throughout the pandemic, regardless of the institution type. CONCLUSIONS: The centralization to certified institutions progressed even during the pandemic. Surgical safety after advanced hepatectomy was satisfactorily maintained in any institution.

PURPOSE: To analyze the clinicopathological features and perioperative outcomes of patients who underwent robot-assisted thoracoscopic surgery (RATS) for primary lung cancer in the initial period after insurance approval in Japan. METHODS: The data source was the National Clinical Database, using four annual datasets (2018, 2019, 2020, and 2021) that included information on individuals who underwent lobectomy with lymph-node dissection via robot-assisted thoracoscopic surgery for primary lung cancer. Clinicopathological features and perioperative outcomes by year were analyzed descriptively. RESULTS: The median console time was reduced by 22 min from 2018 to 2021 (from 171 min to 149 min, respectively). The median overall operative time was also reduced by 29 min from 2018 to 2021 (from 245 min to 216 min, respectively). The conversion rate from robotic to other approaches was 3.5% in 2018 and 2.4% in 2021, with the frequency decreasing each year. The incidence of postoperative complications ranged from 14.6% to 16.6%, and the 90-day mortality rate ranged from 0.3% to 0.5%, with no remarkable change within the study period. CONCLUSIONS: The initial perioperative outcomes of RATS for lung cancer in Japan were favorable. Further accumulation of cases and comparative analyses of long-term outcomes with other approaches are expected.

<h4>Objective</h4>Surgical care has been significantly affected by the COVID-19 pandemic. This study was conducted to evaluate the effects of the pandemic on lung cancer and mediastinal tumor surgery.<h4>Methods</h4>Changes in the number of surgical procedures for lung cancer and mediastinal tumors were analyzed using the National Clinical Database of Japan. Patient characteristics, including disease stage and histological type, from 2019 to 2022 were evaluated using annual datasets.<h4>Results</h4>Comparisons with 2019 showed that the number of patients who underwent surgery for primary lung cancer or a mediastinal tumor decreased in 2020 and then remained stable. There were no clinically significant changes in the trend over the four-year period regarding the number of patients for each clinical and pathological stage of lung cancer. Regarding mediastinal tumors, there was no significant difference in tumor size between years. There was a slight change in the selection of surgical indication during the second quarter of 2020, although its impact on annual trends in the stage distribution for lung cancer and primary disease for mediastinal tumors was minimal.<h4>Conclusions</h4>Analyses of lung cancer and mediastinal tumor surgery cases in Japan during the COVID-19 pandemic showed no significant disease profile changes related to treatment delay.

AIM: The Japanese National Clinical Database, which covers more than 95% of the surgeries performed in Japan, is the largest nationwide database. This is the 2021 annual report of the Gastroenterological Section of the National Clinical Database, which aims to present the short-term outcomes of cases registered in 2021 and discuss significant changes and insights into gastroenterological surgeries observed over the decade. METHODS: We reviewed the data of patients registered in the National Clinical Database between 2012 and 2021. RESULTS: In total, 5 788 093 cases, including 597 780 cases in 2021, were extracted from the National Clinical Database. The number of surgeries resumed its original trend after a uniform decrease due to the coronavirus disease 2019 pandemic. The patient population continues to age, and the proportion of female patients is steadily increasing. The trend of surgeries being conducted in certified institutions with the involvement of board-certified surgeons is consistently rising. Moreover, the increasing trend of endoscopic surgery rate is still maintained. Although operative mortality is declining, the trend of increasing postoperative complications continues. Surgery on the esophagus, liver, and pancreas has shown substantial improvements in operative mortality, with a high participation rate of board-certified surgeons. Surgical procedures with a high incidence of emergency surgeries are characterized by low participation rates of board-certified surgeons, increased morbidity rates, and worse mortality outcomes. CONCLUSION: This overview of surgical patients in Japan, obtained using data extracted from the National Clinical Database, may serve as a critical cornerstone for the future development of gastroenterological surgery.

BACKGROUND: The COVID-19 pandemic had a profound impact on cancer screening, diagnosis, and treatment procedures. We speculated that during the COVID-19 pandemic, sufficient medical resources were maintained in board-certified hospitals, resulting in favorable short-term outcomes, whereas hospital functions in non-board-certified hospitals declined, leading to mortality increase. The aim of this study is to investigate the impact of COVID-19 pandemic on short-term outcomes after esophagectomy, based on the scale of the facilities. METHODS: Data of patients who underwent esophagectomy for esophageal cancer between January 2018 and December 2022 were analyzed using the National Clinical Database (NCD) of Japan. We selected the Authorized Institutes for Board-certified Esophageal Surgeons (AIBCESs) certified by the Japan Esophageal Society (JES) at the hospital level for evaluating the difference in outcomes between institutions. Operative mortality rates and other morbidities were evaluated using the standardized mortality and morbidity ratio (SMR, the ratio of the number of observed patients to the expected number of patients). RESULTS: Within the study period, the annual mean operative mortality rate was higher in non-AIBCESs than in AIBCESs. The SMR showed no significant difference after the COVID-19 pandemic in non-AIBCES for mortality, as well as that in AIBCES. CONCLUSIONS: In non-AIBCESs, no worsening of results caused by the COVID-19 pandemic was observed despite the shortage of medical resources. Our findings highlighted the high quality of esophageal surgery in Japan during the COVID-19 pandemic, a critical situation with limited medical resources.

PURPOSE: To investigate the current status of perioperative venous thromboembolism (VTE) prophylaxis in gastrointestinal surgery in Japan. METHODS: We reviewed data on eight gastroenterological procedures from the Japanese National Clinical Database (NCD), accrued between 2018 and 2020. Patient characteristics, prophylactic methods, postoperative bleeding, cardiac arrest, and postoperative mortality rate within 30 days were retrieved. RESULTS: Despite recommendations, approximately 30% of patients did not receive VTE prophylaxis, suggesting a lack of awareness. Pharmacological prophylaxis was associated with a higher incidence of VTE than mechanical or no prophylaxis for all procedures. Combined prophylaxis resulted in a lower incidence of VTE than pharmacological prophylaxis alone. Pharmacological prophylaxis was also associated with an increased incidence of bleeding events. The risk of cardiac arrest and death was higher in patients with pulmonary embolism (PE), but there was a trend toward lower mortality in the group that received pharmacological prophylaxis. CONCLUSION: Pharmacological prophylaxis for VTE was limited in reducing the incidence of VTE, but it may reduce the risk of death. Combining pharmacological and mechanical prophylaxis tended to be more effective for preventing VTE than either method alone. Conversely, pharmacological prophylaxis may increase the risk of bleeding.

PURPOSE: The National Clinical Database (NCD) in Japan captures over 95% of the surgeries performed by general surgeons. In May 2021, the Japan Hernia Society (JHS) introduced additional categories for groin hernia repair at JHS-registered institutions. This study presents the 2022 data on groin hernia repair from the NCD. METHODS: This study included all cases of groin hernia repair registered in the NCD for 2022. The basic data collected included age, sex, type of surgery, day surgery status, emergency status, and anesthesia involvement. For JHS-registered institutions, data on hernia laterality, whether the case was primary or recurrent, surgical details, and groin hernia classifications were also collected. RESULTS: Of the 908 institutions reporting to the NCD, 459 (50.6%) were JHS registered. A total of 118,365 groin hernia repairs were recorded, of which 43,952 (37.1%) were from JHS-registered institutions. Endoscopic repair accounted for 53.3% (n = 63,208) of the patients. Day surgery was performed in 5.1% (n = 6045) of the patients. At JHS-registered institutions, 81.6% of bilateral hernias were treated by endoscopic repair; 68.1% were lateral hernias. The most commonly used method was the TAPP method, which was applied in 48.8% of cases. CONCLUSIONS: Although endoscopic repair is widely used in Japan, day surgery rates remain low. Improving data collection and increasing NCD participation are crucial for aligning with international standards.

OBJECTIVES: The National Clinical Database (NCD) Urology Division commenced registration in April 2018 in Japan. This is the first report to focus on five surgeries for which detailed information is registered. METHODS: We herein describe annual trends in and the complication grades of the following five surgeries: partial nephrectomy, radical nephrectomy, radical cystectomy, radical prostatectomy, and pyeloplasty, using the NCD. A total of 149 417 patients treated with the five types of surgeries based on NCD data were enrolled in this report. RESULTS: The number of patients was 55 630 for partial/radical nephrectomy from April 2018 to December 2021, 83 653 for radical prostatectomy from April 2018 to December 2021, and 9342 for radical cystectomy from January 2020 to December 2021. In 2021, partial nephrectomy was performed on 7416 cases, radical nephrectomy on 7739 cases, radical prostatectomy on 22 692 cases, radical cystectomy on 4677 cases, and pyeloplasty on 792 cases. CONCLUSIONS: The results obtained showed that a robot-assisted or laparoscopic procedure has replaced open surgery as the common approach for all five surgeries. An analysis of NCD data may be useful for understanding trends in surgical procedures across the major field of urology.

BACKGROUND: The Japanese National Clinical Database (NCD) is a large-scale, nationwide, web-based data entry system that covers the majority of surgical cases performed in Japan. An NCD specializing in urological surgery was launched based on the NCD system in 2018. METHODS: All urological surgeries performed at more than 1000 institutions were registered from 2018. We herein report the number of surgeries conducted as stipulated in the "Certified Urology Surgeon Training Curriculum" between April 2018 and December 2021. RESULTS: A total of 1 377 677 cases were registered from 1185 facilities nationwide under the initiative of the Japanese Urological Association. We examined the number of procedures performed every year for each of the 10 categories. CONCLUSIONS: The NCD system sustainably provides important information relating to the preoperative status, operational outcome, and best practice for urological surgery in Japan.

BACKGROUND: The incidence and prognosis of aortoesophageal fistula (AEF) has not been clarified. The clinical characteristics and surgical outcomes of AEF were investigated. METHODS: The clinical data of patients who underwent surgical treatment for AEF from January 2020 to December 2021 that were registered in the Japan Cardiovascular Surgery Database (JCVSD) were analyzed. RESULTS: During the period, 123 patients (71.0 [IQR: 61.0-78.0] years old; 76.4% men) underwent surgical treatment for AEF. The prevalence of secondary AEF was 61%. Secondary AEF after aortic grafting was the most frequent (n = 40; 32.5%), followed by AEF after thoracic endovascular aortic repair (TEVAR) (n = 30; 24.4%). Operative mortality was observed in 23 patients (18.7%). TEVAR for AEF (p = 0.019), postoperative bleeding (p = 0.047), stroke (p = 0.004), renal failure (p < 0.001), newly required hemodialysis (p = 0.023), pneumonia (p = 0.003), multisystem failure (p < 0.001), and dyslipidemia (p = 0.02) were associated with risk factors of operative mortality after surgical treatment of AEF on univariable logistic regression analyses. CONCLUSIONS: This first nationwide study on the surgical treatment for AEF demonstrated a higher incidence of secondary AEF than primary AEF. Both open surgical repair and TEVAR for AEF were associated with high operative mortality. TEVAR and dyslipidemia were risk factors for operative mortality. Precautions and further improved treatment strategies for AEF are still required.

Esophagectomy for esophageal cancer is a highly invasive gastrointestinal surgical procedure. The National Clinical Database (NCD) of Japan, initiated in 2011, has compiled real-world data on esophagectomy, one of nine major gastroenterological surgeries. This review examines outcomes after esophagectomy analyzed using the Japanese big databases. Certification systems by the Japanese Society of Gastroenterological Surgery (JSGS) and the Japan Esophageal Society (JES) have shown that institutional certification has a greater impact on short-term surgical outcomes than surgeon certification. Minimally invasive esophagectomy has emerged as a viable alternative to open esophagectomy, although careful patient selection is crucial, especially for elderly patients with advanced tumors. The NCD has significantly contributed to the assessment and enhancement of surgical quality and short-term outcomes, while studies based on Comprehensive Registry of Esophageal Cancer in Japan (CRECJ) have provided data on patient characteristics, treatments, and long-term outcomes. The JES has conducted various questionnaire-based retrospective clinical reviews in collaboration with authorized institutions certified by JES. The Diagnosis Procedure Combination (DPC) database provides administrative claims data including itemized prices for surgical, pharmaceutical, laboratory, and other inpatient services. Analyzing these nationwide databases can offer precise insights into surgical quality for esophageal cancer, potentially leading to improved treatment outcomes.

AIM: To examine the potential negative effects of the COVID-19 pandemic on short-term postoperative outcomes of emergency surgery for gastroduodenal perforation in Japan. METHODS: A total of 7973 cases of gastroduodenal perforation from 2019 to 2021 were retrieved from the National Clinical Database (NCD), which includes >95% of surgical cases in Japan. Data were analyzed nationally and in subgroups for subjects in areas with high infection levels (HILs). Postoperative 30-d mortality, surgical mortality, and complications (Clavien-Dindo (CD) grade ≥3) were examined. Months were considered to have significantly high or low mortality or complication rates, if the 95% confidence interval (CI) of the standardized mortality (morbidity) ratio (SMR) does not contain 1. RESULTS: Nationally, data from 2019 vs 2020 and 2021 showed 30-d mortality of 175 (6.7%) vs 398 (7.4%), surgical mortality of 250 (9.5%) vs 537 (10.1%), and complications (CD ≥3) of 558 (21.2%) vs 1163 (21.8%). Among these data, the only significantly high SMR was found for complications in July 2020 (1.36 [95% CI: 1.001-1.80]). In areas with HILs, data from 2019 vs 2020 and 2021 indicated 30-d mortality of 91 (6.3%) vs 215 (7.3%), surgical mortality of 135 (9.4%) vs 294 (10.0%), and complications (CD ≥3) of 304 (21.1%) vs (23.1%). In these data, no month had a significantly high SMR. CONCLUSION: The COVID-19 pandemic had few negative effects on outcomes after surgery for gastroduodenal perforation. These findings suggest that the emergency system for gastroduodenal perforation in Japan was generally maintained during the pandemic.

<jats:title>Abstract</jats:title><jats:sec><jats:title>Aim</jats:title><jats:p>The coronavirus disease 2019 (COVID‐19) pandemic greatly impacted medical resources such as cancer screening, diagnosis, and treatment given to people for various diseases. We surveyed the impacts of the pandemic on the incidence of complications and mortality following pancreaticoduodenectomy for pancreatic cancer in Japan.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>Data on patients who underwent pancreaticoduodenectomy for pancreatic cancer were extracted from the Japanese National Clinical Database (NCD) between 2018 and 2021. The number of the pancreaticoduodenectomy for pancreatic cancer were obtained and then the morbidity and mortality rates were evaluated using a standardized morbidity/mortality ratio (SMR), which is the ratio of the observed number of incidences to the expected number of incidences calculated by the risk calculator previously developed by the NCD.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>This study included 22 255 cases. The number of pancreaticoduodenectomies exhibited an increasing trend even during the COVID‐19 pandemic. The mean observed incidence rates of Grade C pancreatic fistula and Clavien–Dindo grade ≥4 complications, and the 30‐day mortality and surgical mortality rates were 0.8%, 1.8%, 0.8% and 0.9%, respectively. The standardized morbidity ratios did not increase during the COVID‐19 pandemic. The standardized mortality ratios remained within the range of variations observed before the COVID‐19 pandemic.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>The increasing trend in the number of pancreaticoduodenectomies and favorable short‐term outcomes even in the COVID‐19 pandemic suggest the medical care for pancreatic cancer in Japan functioned well during the pandemic.</jats:p></jats:sec>

PURPOSE: We aimed to identify preoperative risk factors for secondary spontaneous pneumothorax surgery. METHODS: The National Clinical Database of Japan, with six annual datasets from 2014 to 2019, was used. All patients who underwent surgery for secondary spontaneous pneumothorax were included, excluding those < 15 years old and those with incomplete data. The effects of preoperative risk factors were analyzed for operative mortality (mortality during hospitalization or within 30 days, regardless of hospitalization status), 30-day mortality, and postoperative respiratory morbidities. RESULTS: Of the 18,309 patients enrolled in the study, operative mortality, 30-day mortality, and postoperative respiratory morbidities were observed in 654 (3.6%), 343 (1.9%), and 2258 (12.3%) patients, respectively. Increasing age, male sex, body mass index < 18.5 or > 30, performance status > 2, emergent surgery, interstitial pneumonia, and diabetes in preoperative co-morbidity, tumors, and other diseases in underlying lung disease were significant risk factors for operative mortality. Those for 30-day mortality included autoimmune disease instead of male sex and diabetes, while those for postoperative respiratory morbidities included lymphangiomyomatosis instead of a body mass index > 30. CONCLUSION: We identified many preoperative risk factors for operative mortality, 30-day mortality, and postoperative respiratory morbidities in secondary spontaneous pneumothorax surgery. These findings will assist in selecting appropriate surgical candidates.

BACKGROUND: The increasing prevalence of frailty has gained considerable attention due to its profound influence on clinical outcomes. However, our understanding of the progression of frailty and long-term clinical outcomes in older individuals with atrial fibrillation remains scarce. METHODS: Using data from 2012 to 2018 from a comprehensive claims database incorporating primary and hospital care records in Shizuoka, Japan, we selected patients aged ≥65 years with atrial fibrillation who initiated oral anticoagulant therapy. The trajectory of frailty was plotted using Sankey plots, illustrating the annual changes in their frailty according to the electronic frailty index during a 3-year follow-up after oral anticoagulant initiation, along with the incidence of clinical adverse outcomes. For deceased patients, we assessed their frailty status in the year preceding their death. RESULTS: Of 6247 eligible patients (45.1% women; mean age, 79.3±8.0 years) at oral anticoagulant initiation, 7.7% were categorized as fit (electronic frailty index, 0-0.12), 30.1% as mildly frail (>0.12-0.24), 35.4% as moderately frail (>0.24-0.36), and 25.9% as severely frail (>0.36). Over the 3-year follow-up, 10.4% of initially fit patients transitioned to moderately frail or severely frail. Conversely, 12.5% of severely frail patients improved to fit or mildly frail. Death, stroke, and major bleeding occurred in 23.4%, 4.1%, and 2.2% of patients, respectively. Among the mortality cases, 74.8% (N=1183) and 3.5% (N=55) had experienced moderately or severely frail and either a stroke or major bleeding in the year preceding their death, respectively. CONCLUSIONS: In a contemporary era of atrial fibrillation management, a minor fraction of older patients on oral anticoagulants died following a stroke or major bleeding. However, their frailty demonstrated a dynamic trajectory, and a substantial proportion of death was observed after transitioning to a moderately or severely frail state.

BACKGROUND: Although curative resection with vascular reconstruction improves the prognosis of blood-invading locally advanced hepatobiliary tumors, the mortality and morbidity of the procedure remains unclear. This study aimed to clarify the risk factors associated with mortality and morbidity in patients undergoing liver resection with vascular reconstruction. METHODS: This retrospective observational study included 1215 patients undergoing hepatectomy of more than one section with vascular reconstruction, except for left lateral sectionectomy registered in the National Clinical Database (NCD) between 2015 and 2019. The rates of surgical mortality and relevant clinical factors were evaluated. RESULTS: Among the four types of vascular reconstruction, portal venous reconstruction was frequently performed in 724 patients (59.6% of the enrolled patients). Surgical mortality was 8.1%. Patients with hepatic artery reconstruction had the highest surgical mortality rate of 15.8%. In other types of reconstruction, surgical mortality was 9.1% in the portal vein, 5.2% in inferior vena cava, and 4.9% in hepatic vein. Factors significantly associated with surgical mortality include age, sex (male), preoperative comorbidity (American Society of Anesthesiologists grade >3, respiratory distress, diabetes, preoperative pneumonia, weight loss, and obstructive jaundice), poorer liver functional reserve (indocyanine green retention rate at 15 min and prothrombin time/international normalized ratio >1.1) and accompanying biliary reconstruction. CONCLUSIONS: The NCD revealed the detailed status of liver resection combined with vascular reconstruction in Japan. Based on the results of this analysis, understanding the factors that influence the outcome and postoperative course of each procedure will provide patients with accurate information and opportunities to improve future outcomes.

OBJECTIVES: This study analyzed the long-term survival of dialysis patients undergoing AVR using the Japanese National Clinical Database with additional survival data. METHODS: De-novo AVR for dialysis-dependent patients between 2010 and 2012 who were registered in the Japan Cardiovascular Surgery Database were included. Concomitant aortic surgery and transcatheter aortic valve replacement were excluded. An additional questionnaire was sent to each hospital regarding the underlying kidney disease, the duration of dialysis initiation to the surgery, and clinical outcomes. The Kaplan-Meier survival curve was descriptively shown for all cohorts and each renal pathology. Furthermore, we compared the incidence of bioprosthetic valve failure in patients who were < 65 years old (group Y) and ≧65 years old (group O). RESULTS: Of these 1529 patients, diabetic nephropathy was 517, chronic glomerulonephritis was 437, and renal sclerosis was 210, regarding renal pathology. 1, 3, and 5-year survival in each pathology was 78.4%, 58.6%, 45.9% in diabetic nephritis, 78.8%, 68.4%, 58.2% in chronic glomerulonephritis, 79.0%, 67.8%, 52.1% in renal sclerosis, and 74.4%, 62.6%, 49.2% in others. Active infectious endocarditis was more prevalent in group Y (O 2.7% vs. Y 9.6%). The incidence of bioprosthetic valve failure requiring re-hospitalization was too small to analyze. 1, 3, and 5-year survival was 76.0%, 63.4%, 49.2% in group O and 74.3%, 64.2%, and 47.7% in group Y. CONCLUSIONS: Long-term survival of AVR for dialysis-dependent was higher in patients with chronic glomerulonephritis and lower in patients with diabetic nephritis than in other pathologies.

PURPOSES: The present study evaluated the impact of clinical guidelines for gastric cancer surgery on surgeons' choice of procedure in real-world practice. We focused on the 2014 guideline revision recommending laparoscopic surgery and the evidence concerning splenectomy for prophylactic lymphadenectomy reported in 2015 using the National Clinical Database, which is the most comprehensive database in Japan. METHODS: We investigated the monthly percentages of laparoscopic distal gastrectomies performed for stage I gastric cancer (LDG%) and splenectomies performed during total gastrectomy for advanced cancer (TGS%) between 2014 and 2017. We evaluated the descriptive statistics of the time-series changes in the LDG%, TGS%, and annual trends of outcomes. RESULTS: In total, 124,787 patients were enrolled. The mean LDG% and TGS% were 69.8% and 9.2%, respectively. The LDG% and TGS% were 66.4% and 16.7%, respectively, in January 2014 and 73.1% and 5.9%, respectively, in December 2017. LDG% consistently increased, and TGS% showed a consistent downward trend throughout the observation period. There was no significant change in this trend after the publication of the guideline recommendations or clinical trial results. CONCLUSION: No significant changes in surgical procedures were observed after publication of the guidelines or results of clinical trials.

PURPOSE: The coronavirus disease 2019 (COVID-19) pandemic limited the delivery of medical resources. Although surgeries are triaged according to disease severity and urgency, a delay in diagnosis and surgery can be detrimental. We conducted this study to analyze data on the impact of the COVID-19 pandemic on pediatric surgery for different diseases or disorders. METHODS: We compiled and compared data on pediatric surgical cases from 2018 to 2020, using the National Clinical Database. The number of diseases, severity, complication rates, mortality rates by disease/disorder, and the COVID-19 pandemic areas were analyzed. RESULTS: The total number of cases of pediatric surgery in 2018, 2019, and 2020 was 50,026, 49,794, and 45,621, respectively, reflecting an 8.8% decrease in 2020 from 2018 and an 8.4% decrease in 2020 from 2019. A decrease was observed when the number of patients with COVID-19 was high and was greater in areas with a low infection rate. There was a marked decrease in the number of inguinal hernia cases. The number of emergency room visits and emergency surgeries decreased, but their relative proportions increased. CONCLUSIONS: The COVID-19 pandemic decreased the number of pediatric surgeries, reflecting the limitations of scheduled surgeries and infection control measures.

AIM: The coronavirus disease 2019 (COVID-19) pandemic has significantly impacted the allocation of medical resources, including cancer screening, diagnosis, and treatment. We aimed to investigate the effects of the pandemic on morbidity and mortality following hepatectomy for hepatocellular carcinoma (HCC). METHODS: We identified patients who underwent hepatectomy for HCC between 2018 and 2021 from the Japanese National Clinical Database (NCD). The number of surgical cases, the use of intensive care units, and the incidence of morbidity were assessed. The standardized morbidity / mortality ratio (SMR) was used to evaluate the rates of morbidity (bile leakage and pneumonia) and mortality in each month, which compares the observed incidence to the expected incidence calculated by the NCD's risk calculator. RESULTS: The study included a total of 10 647 cases. The number of patients undergoing hepatectomy for HCC gradually decreased. The proportion of patients aged 80 years or older increased and that of cases with T1 stage decreased. The proportion of patients who were admitted to the intensive care unit did not change between the pre- and postpandemic period. The mean actual incidence rates of bile leakage, pneumonia, 30-day mortality, and surgical mortality were 9.2%, 2.3%, 1.4%, and 2.1%, respectively. The SMR for the mortalities and morbidities in each month did not increase mostly throughout the COVID-19 pandemic. CONCLUSIONS: The present study showed the decreasing number of resected cases for HCC, while the surgical safety for hepatectomy was enough to be maintained by managing medical resources in Japan.

Abstract Background The COVID‐19 outbreak made conventional medical care impossible, forcing changes in both healthcare providers and patients. In Japan, COVID‐19 infection began spreading in earnest in 2020 and exploded in 2021. There was concern that the medical impact of COVID‐19 in 2021 would differ from that in 2020. We aimed to clarify the impact of COVID‐19 on mortality and anastomotic leakage in laparoscopic surgery for gastric cancer and rectal cancer in Japan using the National Clinical Database (NCD). Methods We collected data from patients who underwent laparoscopic distal gastrectomy (LDG) and laparoscopic low anterior resection (LLAR) from January 2018 to December 2021 from the NCD, a web‐based surgical registration system in Japan. The number of surgical cases, monthly incidence of mortality and morbidity (anastomotic leakage), standardized mortality ratio (SMR), and standardized morbidity‐leakage ratio (SMLR [ratio of observed patients to expected patients calculated using the risk calculator established in the NCD]) were evaluated. Results The numbers of LDG and LLAR cases continued to decline in the first year of the pandemic in 2020 and were as low in 2021 as in 2020. Although the numbers of robot‐assisted LDG and LLAR cases increased, the growth rate was lower than the rate of increase prior to the pandemic. Mortality and anastomotic leakage, two of the most important complications, as assessed by SMR and SMLR, did not worsen during the pandemic in comparison to the pre‐pandemic period. Conclusions Laparoscopic surgeries were performed safely in Japan and were not affected by the COVID‐19 pandemic.

<jats:title>Abstract</jats:title><jats:sec><jats:title>Background</jats:title><jats:p>Anemia has negative effects on long‐term outcomes of rectal cancer patients; however, its status as a risk factor for severe complications is disputed. Perioperative risks may differ based on the severity of pre‐surgical anemia; nonetheless, no previous study has investigated these differences. This study identified risks of severe postoperative complications in rectal cancer patients based on severity of their pre‐surgical anemia.</jats:p></jats:sec><jats:sec><jats:title>Materials and Methods</jats:title><jats:p>This study enrolled patients who underwent low anterior resection for rectal cancer and were registered in the Japanese National Clinical Database (NCD) between 2017 and 2019. Anemia severity was categorized into three levels: mild, moderate, and severe. A logistic regression model was applied to calculate the risk‐adjusted odds ratio (OR) of severe complications after surgery.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>This study analyzed a cohort of 51 765 rectal cancer patients who underwent low anterior resection. Results showed that severe complications occurred in 10.9% of patients and were significantly more frequent in patients with anemia (13.6%) than those with normal hemoglobin levels (9.2%). Risk‐adjusted ORs of severe complications in the severe, moderate, and mild anemia groups versus the normal group for males were 1.19 (95% confidence interval [CI]: 0.89–1.58), 1.47 (1.34–1.62), and 1.21 (1.12–1.31), respectively. Those for females were 1.39 (0.90–2.15), 1.64 (1.37–1.97), and 1.36 (1.16–1.58), respectively.</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>According to this large cohort study, pre‐surgical anemia significantly increases the risk of severe postoperative complications in rectal cancer patients. Even mild anemia presents a significant risk.</jats:p></jats:sec>

PURPOSE: The volume of surgical services has significantly reduced globally due to the coronavirus disease 2019 (COVID-19) pandemic. This study evaluated the level of recovery in terms of the number of operations performed in Japan in 2021, based on nationwide periodic surveillance. METHODS: Information on the weekly and annual volumes of 20 representative procedures in 6 surgical subspecialties in 2021 was extracted from the National Clinical Database. Statistical data for 2018 and 2019 (pre-pandemic era) were compared with those for 2020. Data on waves of infection, peak period, and high-prevalence areas (13 of 47 prefectures) were analyzed individually. RESULTS: The volumes of the 10 procedures, including gastrectomy, hepatectomy, valve replacement and valve plasty, coronary artery bypass grafting, infrarenal abdominal aorta replacement, ventricular septal defect closure, lung lobectomy, inguinal hernia repair (age < 16 years old), and appendectomy (age < 16 years old), did not reach 95% of that in the pre-pandemic era. The most striking decline in the surgical volume of these 10 procedures was observed during the peak period of wave 5 in high-prevalence areas. CONCLUSION: This near-complete enumeration survey identified the polarization of 20 representative procedures in terms of resumption of surgical service after the pandemic.

PURPOSE: The relationship between board certification, clinical guideline implementation, and quality of gastric cancer surgery remains unclear. METHODS: A web-based questionnaire survey was administered to departments registered in the National Clinical Database (NCD) of Japan between October 2014 and January 2015. Quality indicators (QIs) based on the Donabedian model were evaluated. Structural QIs (e.g., affiliations with academic societies and board certifications) and process QIs (adherence to clinical practice guidelines for gastric cancer) were assessed using risk-adjusted odds ratios (AORs) for surgical mortality. Multivariable logistic regression models with a generalized estimating equation were used. RESULTS: A total of 835 departments performing 40,992 distal gastrectomies and 806 departments performing 19,618 total gastrectomies responded. Some certified institutions and physicians showed significant associations, with lower AORs for surgical mortality. Important process QIs included pre- and postoperative abdominal CT scanning, endoscopic resection based on progression, curative resection with D2 dissection for advanced gastric cancer, laparoscopic surgery, and HER2 testing for patients with unresectable recurrent gastric cancer. CONCLUSIONS: Multiple structural and process QIs are associated with surgical mortality after gastrectomy in Japan. Measuring and visualizing QIs may enhance healthcare improvements.

PURPOSE: The current study was designed to analyze the impact of the COVID-19 pandemic on general thoracic surgeries in Japan. METHODS: Changes in surgeries for lung cancer and metastatic lung tumors were evaluated based on National Clinical Database data regarding cancer screening. RESULTS: In 2021, surgeries for primary lung cancer increased by 3.4% compared to 2020, which, given the increase from 2014 to 2019, indicates an overall 11.1% decrease. In contrast, surgeries for metastatic lung tumors in 2021 decreased by 5.8% compared to 2020, which, given the increase from 2014 to 2020, indicates an overall 9.2% decrease. Half of the primary diseases for metastatic lung tumor were cases of colorectal cancer. Low anterior resection procedures in 2020 decreased by 5.5% compared to 2019. Lung and colon cancer screening examinees in 2021 were increased compared to 2020; however, they still showed respective decreases of 11% and 9.0% compared to 2019. CONCLUSIONS: Surgeries for primary lung cancer still decreased substantially during the COVID-19 pandemic. The continued stagnation of screening was responsible for this decrease. Surgeries for metastatic lung tumors decreased profoundly, and the decrease in screening for primary tumors was responsible for this reduction. Our findings emphasize the significance of maintaining cancer screening efforts, even during a pandemic.

BACKGROUND: There are few studies on the impact of a colorectal-specific technically certified surgeon on good surgical outcome for laparoscopic low anterior resection in the real world. OBJECTIVE: To evaluate the short-term outcomes of laparoscopic low anterior resection with the participation of a certified colorectal surgeon. DESIGN: This was a retrospective cohort study using Japanese nationwide database. SETTING: This study was conducted as a project for the Japan Society of Endoscopic Surgery and Japanese Society of Gastroenterological Surgery. PATIENTS: This study included 41,741 patients listed in the National Clinical Database who underwent laparoscopic low anterior resection performed by certified, non-certified, and colorectal-specific certified surgeons, according to Endoscopic Surgical Skill Qualification System from 2016 to 2018. MAIN OUTCOME MEASURES: Operative mortality rate and Anastomotic leak rate were the primary outcomes. RESULTS: Overall 30-day mortality and operative mortality were 0.2% and 0.3%, respectively, without significant differences between the all kinds of certified and non-certified surgeon groups. Overall anastomotic leak rate was 9.3%, with a significant difference between the two groups. Colorectal- and stomach-certified groups had lower 30-day mortality and operative mortality than the biliary-certified and non-certified groups. The anastomotic leak rate was the lowest in the colorectal-certified group. Based on a logistic regression analysis using the risk-adjusted model, operative mortality was significantly higher in the biliary-certified group than in the colorectal-certified group. Moreover, anastomotic leak rate was significantly lower in the colorectal-certified group than in the stomach-certified and non-certified groups. LIMITATIONS: This study was a retrospective study and there was a possibility of different definitions of anastomotic leak due to the use of a nationwide database. CONCLUSIONS: The participation of a colorectal-specific video-certificated surgeon may decrease the risk of operative mortality and anastomotic leak for laparoscopic low anterior resection.

<jats:title>Abstract</jats:title><jats:sec><jats:title>Aim</jats:title><jats:p>The Coronavirus Disease 2019 (COVID‐19) pandemic affected the allocation of various medical resources to several areas, including intensive care units (ICUs). However, currently, its impact on the short‐term postoperative outcomes of gastrointestinal cancer surgeries remains unclear. We aimed to evaluate the impact of the pandemic on the incidence of complications occurring after low anterior resection in patients with rectal cancer in Japan.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>Data from the Japanese National Clinical Database between 2018 and 2021 were retrospectively examined. The primary outcome of the study was the postoperative morbidity and mortality rates before and after COVID‐19 pandemic. Moreover, the postoperative ICU admission rate was assessed. Morbidity and mortality rates were also assessed using a standardized morbidity/mortality ratio (SMR, the ratio of the actual number of incidences to the expected number of incidences calculated by the risk calculator).</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>This study included 74 181 patients, including 43 663 (58.9%) from COVID‐19 epidemic areas. The mean actual incidences of anastomotic leakage (AL) and pneumonia during the study period were 9.2% and 0.9%, respectively. The SMRs of these complications did not increase during the pandemic but those of AL declined gradually. The mean 30‐day mortality and operative mortality rates were 0.3% and 0.5%, respectively. Moreover, SMRs did not change significantly in the pandemic or regional epidemic status. The ICU admission rate temporarily decreased, especially in the epidemic areas.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>Although the pandemic temporarily decreased the ICU admission rate, its impact on short‐term outcomes following low anterior resection in patients with rectal cancer was insignificant in Japan.</jats:p></jats:sec>

AIM: This study aimed to evaluate the impact of the coronavirus disease (COVID-19) pandemic on elective endoscopic surgeries in Japan using the National Clinical Database. METHODS: We retrospectively analyzed the clinicopathological factors and surgical outcomes of laparoscopic cholecystectomy (LC), laparoscopic distal gastrectomy (LDG), and laparoscopic low anterior resection (LLAR) and compared the monthly numbers of each procedure performed in 2020 with those in 2018 and 2019. The degree of infection in prefectures was classified into low and high groups. RESULTS: In 2020, the number of LCs (except for acute cholecystitis) was 76 079 (93.0% of that in 2019), the number of LDGs was 14 271 (85.9% of that in 2019), and the number of LLARs was 19 570 (88.1% of that in 2019). Although the number of robot-assisted LDG and LLAR cases increased in 2020, the growth rate was mild compared with that in 2019. There was little difference in the number of cases in the degree of infection in the prefectures. The numbers of LC, LDG, and LLAR cases decreased from May to June and recovered gradually. In late 2020, the proportion of T4 and N2 cases of gastric cancer and the number of T4 cases of rectal cancer increased compared with those in 2019. There was little difference between the proportions of postoperative complications and mortality in the three procedures between 2019 and 2020. CONCLUSION: The number of endoscopic surgeries decreased in 2020 as a result of the COVID-19 pandemic. However, the procedures were performed safely in Japan.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic had adversely impacted cancer screening, diagnosis, and treatment. We investigated the change in medical resource, such as the intensive care unit use, and short-term outcomes after esophagectomy during the pandemic. METHODS: Data of patients who underwent esophagectomy for esophageal cancer registered in the National Clinical Database (NCD) in Japan from January 2018 to December 2021 were analyzed. The time series change in the number of surgical cases; usage of intensive care unit; incidence of morbidity and mortality; standardized mortality and morbidity ratio (SMR) for 30-days mortality; surgical mortality; and morbidities for pneumonia, sepsis, unplanned intubation, and anastomotic leakage were evaluated. RESULTS: The annual number of patients undergoing esophagectomy remained similar from 2018 to 2021. The negative impact of the pandemic on medical resources was strongly identified in the patients from an epidemic area where there is a higher cumulative number of infections per population as compared to all prefectures. The proportions of patients admitted to the intensive care unit were 91.4%, 93.0%, 91.6%, and 90.5% in 2018, 2019, 2020, and 2021, respectively. Moreover, 93.3%, 94.0%, 92.0%, and 90.9% patients who underwent surgery in an epidemic area were admitted to the intensive care unit in 2018, 2019, 2020, and 2021, respectively. However, the morbidity and mortality rates during the pandemic did not worsen according to the SMR values. CONCLUSIONS: Esophagectomy was performed during the pandemic despite limited medical resources by a systematic endeavor of the entire surgical department in Japan, without increasing the incidence rate of worse outcome.

PURPOSE: To investigate the incidence of postoperative cerebral infarction after curative lobectomy, its association with the type of lobectomy, and how postoperative new-onset arrhythmia contributes to postoperative cerebral infarction. METHODS: The subjects of this analysis were 77,060 patients who underwent curative lobectomy for lung cancer between 2016 and 2018 according to the National Clinical Database. Incidences of postoperative cerebral infarction and postoperative new-onset arrhythmia were analyzed. Moreover, mediation analysis was performed to evaluate the causal pathway between postoperative new-onset arrhythmia and postoperative cerebral infarction. RESULTS: Postoperative cerebral infarction occurred in 110 (0.7%) patients after left upper lobectomy and in 85 (0.7%) patients after left lower lobectomy. Left upper lobectomy and left lower lobectomy were associated with a higher likelihood of postoperative cerebral infarction than right lower lobectomy. Left upper lobectomy was the strongest independent predictor of postoperative new-onset arrhythmia. However, in the mediation analysis, the odds ratio for cerebral infarction did not change after the addition of the factor of postoperative new-onset arrhythmia. CONCLUSION: Cerebral infarction occurred significantly more often not only after left upper lobectomy, but also after left lower lobectomy. Postoperative new-onset arrhythmia was less likely to be related to cerebral infarction after left upper lobectomy.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic had resulted in either failure to provide required medical resources or delayed treatment for gastric cancer patients. This study aimed to investigate the impact of COVID-19 on the incidence of postoperative complications using a nationwide Japanese database of patients undergoing distal gastrectomy for gastric cancer. METHODS: We collected the data of patients who underwent distal gastrectomy from January 2018 to December 2021 from the National Clinical Database (NCD), a web-based surgical registration system in Japan. The number of surgical cases, the use of intensive care units, and the incidence of morbidity per month were analyzed. We also calculated the standardized mortality ratio (SMR), defined as the ratio of the number of observed patients to the expected number of patients calculated using the risk calculator established in the NCD, for several morbidities, including pneumonia, sepsis, 30-day mortality, and surgical mortality. RESULTS: A decrease of 568 gastrectomies was observed from April 2020 to May 2020. Although the absolute number of patients admitted to intensive care units had declined since 2020, the proportion of patients admitted to the ICU did not change before and after the pandemic. Mortality and critical morbidity (such as pneumonia and sepsis) rates were not worse during the pandemic compared to pre-pandemic periods per the SMR. CONCLUSIONS: Surgical management was conducted adequately through the organized efforts of the entire surgery department in our country even in a pandemic during which medical resources and staff may have been limited.

AIM: The National Clinical Database (NCD) of Japan is a nationwide data entry system for surgery, and it marked its 10th anniversary in 2020. The aim was to present the 2020 annual report of gastroenterological surgery of the NCD. METHODS: The data of the surgical procedures stipulated by the training curriculum for board-certified surgeons of the Japanese Society of Gastroenterological Surgery in the NCD from 2011 to 2020 were summarized. RESULTS: In total, 5 622 845 cases, including 593 088 cases in 2020, were extracted from the NCD. The total number of gastroenterological surgeries increased gradually in these 10 years, except for the year 2020 due to the COVID-19 pandemic. The annual number of surgeries of each organ, except the pancreas and liver, decreased by 0.4%-13.1% in 2020 compared to 2019. The surgical patients were consistently aging, with more than 20% of all gastroenterological surgeries in 2020 involving patients aged 80 years or older. The participation of board-certified surgeons increased for each organ (75.9%-95.7% in 2020). The rates of endoscopic surgery also increased constantly. Although the incidences of postoperative complications of each organ increased by 0.7%-7.9% in these 10 years, postoperative mortality rates decreased by 0.2%-1.5%. CONCLUSIONS: We present here the short-term outcomes of each gastroenterological operative procedure in 2020. This review of the 10-years of NCD data of gastroenterological surgery revealed a consistent increase of the number of surgeries (except for in 2020), especially endoscopic procedures, and aging of the Japanese population. The good safety of Japanese gastroenterological surgeries was also indicated.

PURPOSE: Minimally invasive surgery (MIS) for thymic tumors is now accepted widely, in line with improved surgical techniques; however, we occasionally encounter complicated cases of large tumors or of total thymectomy requiring prolonged operative duration or conversion to an open procedure (OP). We reviewed patients registered in a nationwide database to identify the technical feasibility of MIS for thymic epithelial tumors. METHODS: Data on patients treated surgically between 2017 and 2019 were extracted from the National Clinical Database of Japan. Clinical factors and operative outcomes were calculated by tumor diameter using trend analyses. Perioperative outcomes of MIS for non-invasive thymoma were investigated using propensity score-matched analyses. RESULTS: MIS was performed in 46.2% of the patients. The operative duration and conversion rate increased with the tumor diameter (p < .001). After propensity score-matching, operative duration and postoperative hospital stay were shorter (p < .001), and the transfusion rate was lower (p = .007) in patients who underwent MIS than in those who underwent OP for thymomas ≥ 5 cm. Among patients who underwent total thymectomy, blood loss was less (p < .001) and the postoperative hospital stay was shorter (p < .001) in those who underwent MIS than in those who underwent OP. There were no significant differences in postoperative complications and mortality. CONCLUSIONS: MIS is technically feasible even for large non-invasive thymomas or for total thymectomy, although the operative duration and open conversion rate increase with the tumor diameter.

BACKGROUND: Proficiency of the operating surgeon is one of the most critical factors potentially associated with reductions in complications and surgery-related mortality. With video-rating systems having shown potential for assessing laparoscopic surgeons' proficiency, the Endoscopic Surgical Skill Qualification System (ESSQS) was developed by the Japan Society for Endoscopic Surgery to subjectively assess the proficiency of laparoscopic surgeons by rating applicants' non-edited case videos. We conducted a study to evaluate how ESSQS skill-qualified (SQ) surgeon involvement influences short-term outcomes of laparoscopic gastrectomy performed for gastric cancer. METHODS: Data from the National Clinical Database regarding laparoscopic distal and total gastrectomy performed for gastric cancer between January 2016 and December 2018 were analyzed. Operative mortality, defined as 30-day mortality or 90-day in-hospital mortality, and anastomotic leakage rates were compared per involvement vs. non-involvement of an SQ surgeon. Outcomes were also compared per involvement of a gastrectomy-, colectomy-, or cholecystectomy-qualified surgeon. The association between the area of qualification and operative mortality/anastomotic leakage was also analyzed with a generalized estimating equation logistic regression model used to account for patient-level risk factors and institutional differences. RESULTS: Of 104,093 laparoscopic distal gastrectomies, 52,143 were suitable for inclusion in the study; 30,366 (58.2%) were performed by an SQ surgeon. Of 43,978 laparoscopic total gastrectomies, 10,326 were suitable for inclusion; 6501 (63.0%) were performed by an SQ surgeon. Gastrectomy-qualified surgeons outperformed non-SQ surgeons in terms of both operative mortality and anastomotic leakage. They also outperformed cholecystectomy- and colectomy-qualified surgeons in terms of operative mortality or anastomotic leakage in distal and total gastrectomy, respectively. CONCLUSION: The ESSQS appears to discriminate laparoscopic surgeons who can be expected to achieve significantly improved gastrectomy outcomes.

BACKGROUND: In older patients with atrial fibrillation (AF), frailty is frequently prevalent. However, the prognostic value of frailty for adverse events after initiation of oral anticoagulants (OACs) is unclear. OBJECTIVES: We assessed whether frailty at the time of OAC initiation is associated with subsequent bleeding or embolic events. METHODS: We extracted patients aged ≥65 years with nonvalvular AF in whom OACs were initiated from a universal administrative claims database incorporating primary and hospital care records in Shizuoka, Japan, between 2012 and 2018. Frailty was assessed using the electronic frailty index (eFI). The association of frailty with bleeding events and ischemic stroke/transient ischemic attack were evaluated using the Fine-Gray model and restricted cubic spline model. RESULTS: Among 12,585 patients with AF, 7.8% were categorized as fit, 31.5% as mildly frail, 34.8% as moderately frail, and 25.9% as severely frail. The risk of bleeding was associated with a higher eFI (adjusted subdistribution hazard ratio [95% CI] for fit or mild frailty: 1.15 [1.02-1.30]; moderate frailty: 1.42 [1.24-1.61]; and severe frailty: 1.86 [1.61-2.15]), whereas the association was weaker for ischemic stroke/transient ischemic attack. The spline models demonstrated that the relative hazard for bleeding increased steeply with increasing eFI. CONCLUSION: Patients with frailty in whom OAC therapy is initiated have higher risk of bleeding, highlighting the importance of discussing this increased risk with patients with AF who have frailty and assessing frailty at the time of OAC initiation.

BACKGROUND: This study shows an analysis of long-term survival of dialysis-dependent patients undergoing aortic valve replacement (AVR) using the Japan National Clinical Database and additional data. METHODS: Dialysis-dependent patients with de-novo AVR between 2010 and 2012 registered in the database were included. Concomitant aortic surgery and transcatheter aortic valve replacement were excluded. Additional data on the underlying kidney disease, the duration of dialysis, and clinical outcomes were registered between October 29, 2019, and August 30, 2020. The primary outcome was all-cause mortality. The secondary outcomes were cerebral infarction, cerebral bleeding, gastrointestinal bleeding, and prosthetic valve failure. RESULTS: After propensity score matching, 1016 cases (508 each in bioprosthetic and mechanical valve group) were matched. The median follow-up period was 3.29 years (IQR; 0.59 years, 6.25 years). The median survival time was 5.38 years (IQR 1.20 and 9.26 years) in the mechanical valve group and 4.98 years (IQR 1.69 and 9.62 years) in the bioprosthetic valve group. The Cox regression model showed no significant difference in long-term survival between groups (mechanical valve; HR 0.895, 95% CI 0.719-1.113, p=0.318). The incidence of cerebral infarction and prosthetic valve failure requiring admission were similar between groups. Cerebral (HR 2.143, 95% CI 1.125-4.080, p=0.002) and gastrointestinal bleeding (HR 2.071, 95% CI 1.243-3.451, p=0.0005) were more frequent in the mechanical valve group. CONCLUSIONS: Long-term survival of dialysis-dependent patients was similar regardless of whether mechanical or bioprosthetic valves were implanted. The incidences of cerebral and gastrointestinal bleeding were twofold higher in the mechanical valve group.

AIM: This study aimed to investigate the effect of the coronavirus disease pandemic on the number of surgeries for gastroenterological cancer cases in Japan. METHODS: The data recorded in the National Clinical Database of Japan between 2018 and 2020 were utilized for this study. Five specific surgeries for primary cancers and surgery for acute diffuse peritonitis were considered the primary endpoints. We divided the study period into the prepandemic and postpandemic (after April 2020) periods and examined the number of surgeries in relation to clinical factors. RESULTS: Overall, 228 860 surgeries were analyzed. Among the five primary cancer surgeries, the number of distal gastrectomies for gastric cancer decreased the most (to 81.0% of the monthly number in the prepandemic period), followed by that of low anterior resections for rectal cancer (91.4%). In contrast, the number of pancreaticoduodenectomies for pancreatic cancer increased by 7.1%, while that of surgeries for peritonitis remained stable. This trend was observed nationwide. We also noted a marked reduction in the number of distal gastrectomy (to 72.5%), low anterior resection (84.0%), and esophagectomy (88.8%) procedures for T1 tumors. The noncurative resection rate and mortalities were low despite the increased proportion of T4 tumors and older patients. CONCLUSION: A marked reduction in surgeries for gastric and rectal cancers with early T factors may reflect prioritization of surgeries and reduction in cancer screenings. Although the quality of the surgery was maintained in terms of reduced mortalities and morbidities, the long-term effects of this pandemic should be monitored.

OBJECTIVES: This study aimed to compare the real-world outcomes of segmentectomy and lobectomy for lung cancer after adjusting for background factors and the extent of lymphadenectomy. METHODS: This retrospective cohort study used a nationwide database in Japan. The data of patients with clinical stage 0/IA lung cancer who underwent segmentectomy or lobectomy between 2017 and 2019 were retrieved. Short-term postoperative outcomes were compared between the segmentectomy and lobectomy groups using propensity score-matched analysis. RESULTS: In the total cohort of 59 663 patients, 11 975 and 47 688 patients were in the segmentectomy and lobectomy groups, respectively. After propensity-score matching, 8 426 matched patients from each group were retrieved. All confounders including age, sex, comorbidities, smoking history, respiratory function, tumour size, clinical stage, affected lobe and extent of lymphadenectomy were appropriately adjusted. The overall complication rate and the cardiopulmonary complication rate were lower in the segmentectomy group than in the lobectomy group (8.5% versus 11.2%, p < 0.001 and 7.5% versus 10.3%, p < 0.001, respectively). The incidence of prolonged air leak was also lower after segmentectomy than after lobectomy (3.6% versus 5.3%). Surgical mortality, operative time and blood loss volume were comparable between the two groups. CONCLUSIONS: The postoperative complication rate was lower with segmentectomy than with lobectomy for early-stage lung cancer.

OBJECTIVES: The aim of this study was to reveal the neurological outcomes of choking-induced out-of-hospital cardiac arrest (OHCA) and evaluate the presence of witnesses, cardiopulmonary resuscitation (CPR) performed by a witness (bystander-witnessed CPR), and the proportion of patients with favourable neurological outcomes by the time from CPR by emergency medical services (EMS) to the return of spontaneous circulation (ROSC) (CPR-ROSC time). METHODS: We retrospectively analysed the SOS-KANTO 2012 database, which included data of 16,452 OHCAs in Japan. We selected choking-induced OHCA patients aged ≥ 20 years. We evaluated the neurological outcomes at 1 month with the Cerebral Performance Category (CPC). We defined favourable neurological outcomes (CPCs: 1-2) and present the outcomes with descriptive statistics. RESULTS: Of 1,045 choking-induced OHCA patients, 18 (1.7%) had a favourable neurological outcome. Of 1,045 OHCAs, 757 (72.6%) were witnessed, and 375 (36.0%) underwent bystander-witnessed CPR. Of the 18 OHCAs with favourable outcomes, 17 (94.4%) were witnessed, and 11 (61.1%) underwent bystander-witnessed CPR. With a CPR-ROSC time of 0-5 minutes, the proportion of patients with favourable neurological outcomes was 29.7%, ranging from 0% to 6% in the following time groups. CONCLUSIONS: The neurological outcome of choking-induced OHCA was poor. The neurological outcomes deteriorated rapidly from 5 minutes after the initiation of CPR by EMS. The presence of witnesses and bystander-witnessed CPR may be factors that contribute to improved outcomes, but the effects were not remarkable. As another approach to reduce deaths due to choking, citizen education for the prevention of choking may be effective.

Autosomal dominant polycystic kidney disease (ADPKD) is a rare hereditary disease leading to end-stage renal failure in approximately half of patients by seventy years of age. It is important to continuously take tolvaptan to control disease progression. However, adherence to tolvaptan in a real-world setting, rather than randomized controlled trials (RCTs), has not been sufficiently reported. We aimed to investigate tolvaptan persistence among patients with ADPKD using a large claims database. Using the Shizuoka Kokuho Database, we identified patients diagnosed with ADPKD who were prescribed tolvaptan from March 2014-September 2018 in Japan. The persistence rate of tolvaptan medication was estimated by Kaplan-Meier analysis, and patient background factors associated with treatment discontinuation were exploratively evaluated with log-rank tests. We identified 1714 eligible patients with ADPKD, and among them, 25 patients used tolvaptan medication. We followed up these patients, whose median treatment duration was 21 months. The persistence rates at 12, 24, and 36 months were estimated to be 70.8% (95% confidence interval: 48.2-93.4), 46.5% (23.2-66.9), and 38.7% (16.4-60.8), respectively. In the exploratory analysis, there were no factors that were obviously associated with tolvaptan discontinuation. The persistence rate of tolvaptan in patients with ADPKD in a real-world setting may be lower than that in previous RCTs. Our innovative method, particularly in Japan, to analyze adherence using large claims data should change the way clinical epidemiological research and health policies of rare diseases are designed in the future.

OBJECTIVE: The COVID-19 pandemic has far-reaching collateral health impacts on the ongoing delivery of surgical care worldwide. The current study was designed to analyze the impact of the COVID-19 pandemic on the number of surgeries of general thoracic surgery in Japan. METHODS: Changes in the number of surgeries for total and three representative tumors were analyzed using the National Clinical Database data with reference to the pandemic infection rate and lung cancer screening. RESULTS: In 2020, the number of surgeries in total and for primary lung cancer and mediastinal lung tumor decreased by 4.9, 5.1, and 5.0 %, respectively. Considering the five-year trend towards a 5 % annual increase, there was a potential 10 % decrease in the number of primary lung cancer surgeries. The number of primary lung cancer surgeries bottomed in July 2020 but recovered towards the end of the year. In contrast, the number of metastatic lung tumor surgeries in 2020 increased by 3.2 %, following a similar trend observed over the previous five years. The number of lung cancer screening examinees decreased markedly with the lowest number in May. Our findings indicate that surgical triage had a limited impact on the decrease in primary lung cancer surgeries during the pandemic; rather, the decrease in lung cancer screening, which was a few months preceding, is most likely responsible. CONCLUSIONS: The decrease in primary lung cancer was mainly caused by the decrease in lung cancer screening, indicating that continuing screening is vital even during a pandemic.

Abstract Objective To compare short term surgical outcomes between male and female gastrointestinal surgeons in Japan. Design Retrospective cohort study. Setting Data from the Japanese National Clinical Database (includes data on &gt;95% of surgeries performed in Japan) (2013-17) and the Japanese Society of Gastroenterological Surgery. Participants Male and female surgeons who performed distal gastrectomy, total gastrectomy, and low anterior resection. Main outcome measures Surgical mortality, surgical mortality combined with postoperative complications, pancreatic fistula (distal gastrectomy/total gastrectomy only), and anastomotic leakage (low anterior resection only). The association of surgeons’ gender with surgery related mortality and surgical complications was examined using multivariable logistic regression models adjusted for patient, surgeon, and hospital characteristics. Results A total of 149 193 distal gastrectomy surgeries (male surgeons: 140 971 (94.5%); female surgeons: 8222 (5.5%)); 63 417 gastrectomy surgeries (male surgeons: 59 915 (94.5%); female surgeons: 3502 (5.5%)); and 81 593 low anterior resection procedures (male surgeons: 77 864 (95.4%); female surgeons: 3729 (4.6%)) were done. On average, female surgeons had fewer post-registration years, operated on patients at higher risk, and did fewer laparoscopic surgeries than male surgeons. No significant difference was found between male and female surgeons in the adjusted risk for surgical mortality (adjusted odds ratio 0.98 (95% confidence interval 0.74 to 1.29) for distal gastrectomy; 0.83 (0.57 to 1.19) for total gastrectomy; 0.56 (0.30 to 1.05) for low anterior resection), surgical mortality combined with Clavien-Dindo grade ≥3 complications (adjusted odds ratio 1.03 (0.93 to 1.14) for distal gastrectomy; 0.92 (0.81 to 1.05) for total gastrectomy; 1.02 (0.91 to 1.15) for low anterior resection), pancreatic fistula (adjusted odds ratio 1.16 (0.97 to 1.38) for distal gastrectomy; 1.02 (0.84 to 1.23) for total gastrectomy), and anastomotic leakage (adjusted odds ratio 1.04 (0.92 to 1.18) for low anterior resection). Conclusion This study found no significant adjusted risk difference in the outcomes of surgeries performed by male versus female gastrointestinal surgeons. Despite disadvantages, female surgeons take on patients at high risk. Greater access to surgical training for female physicians is warranted in Japan.

BACKGROUND: Two prominent patient positions during thoracoscopic esophagectomy are the left lateral decubitus position (LP) and the prone position (PP). However, whether the patient position during thoracoscopic esophagectomy influences short-term outcomes, especially postoperative pneumonia, remains unclear. We aimed to elucidate the impact of patient position on the occurrence of postoperative pneumonia. METHODS: We analyzed 9850 patients who underwent oncologic thoracoscopic esophagectomies between 2016 and 2019 from the National Clinical Database. We compared the short-term outcomes between the LP and PP groups, and the primary outcome measure was the incidence of postoperative pneumonia. RESULTS: This study included 2637 (26.8%) and 7213 (73.2%) patients in the LP and the PP groups, respectively. The baseline characteristics of the two groups were well-balanced. Compared with the LP group, the PP group had a longer operative time and less blood loss. There were no significant differences in the incidences of postoperative pneumonia, recurrent laryngeal nerve palsy, anastomotic leakage, severe complications, and reoperation between the groups. Meanwhile, prolonged ventilation and surgery-related mortality occurred more frequently in the LP than in the PP group (P < 0.001 and 0.046, respectively). After multivariable adjustment, the patient position did not significantly influence the incidence of postoperative pneumonia (odds ratio 0.91, 95% confidence interval 0.80-1.04). CONCLUSIONS: Although prolonged ventilation and surgery-related mortality occurred more frequently in the LP group than in the PP group, the patient position did not significantly influence the occurrence of postoperative pneumonia.

Objective: Anemia is a common complication of chronic kidney disease (CKD). The aim of this study was to evaluate the hemoglobin levels at the initiation of erythropoiesis stimulating agent (ESA) therapy in patients with non-dialysis-dependent CKD (NDD-CKD) and anemia using a large-scale administrative database in Japan.Methods: The longitudinal data of adult patients who initiated ESA therapy between April 2008 and December 2018 were extracted from a hospital-based administrative database. The primary outcome was the hemoglobin level at the initiation of ESA therapy, whereas the exploratory outcome was the hemoglobin level recorded 6 months after the onset of the ESA therapy.Results: A total of 4939 patients were included in the primary analysis. The mean hemoglobin level at the initiation of ESA therapy was 9.1 g/dL, which was lower than the level (11 g/dL) recommended for the initiation of treatment by the current Japanese treatment guidelines. Moreover, 42.1% and 15.0% of the patients had hemoglobin levels <9.0 and <8.0 g/dL, respectively, at the initiation of ESA therapy. In 2964 patients for whom hemoglobin levels at 6 months after the initiation of ESA therapy were available, the mean hemoglobin level increased to 10.3 g/dL, and 61.9% and 31.1% of these patients had hemoglobin levels ≥10.0 and >11.0 g/dL, respectively.Conclusion: This real-world database study revealed that the hemoglobin levels at the initiation of ESA therapy in new users of ESA were lower than those recommended by the treatment guidelines in Japan.

Importance: Women are vastly underrepresented in surgical leadership and management in Japan. The lack of equal opportunities for surgical training is speculated to be the main reason for this disparity; however, this hypothesis has not been investigated thus far. Objective: To examine gender disparity in the number of surgical experiences among Japanese surgeons. Design, Setting, and Participants: This retrospective, multicenter cross-sectional study used data from the National Clinical Database, which contains more than 95% of all surgical procedures in Japan. Participants included male and female gastroenterological surgeons who performed appendectomy, cholecystectomy, right hemicolectomy, distal gastrectomy, low anterior resection, and pancreaticoduodenectomy between January 1, 2013, and December 31, 2017. Exposures: Differences in the number of surgical experiences between male and female surgeons. Main Outcomes and Measures: The primary outcomes were the total number of operations and number of operations per surgeon by gender and years of experience. Data were analyzed from March 18 to August 31, 2021. Results: Of 1 147 068 total operations, 83 354 (7.27%) were performed by female surgeons and 1 063 714 (92.73%) by male surgeons. Among the 6 operative procedures, the percentage of operations performed by female surgeons were the highest for appendectomy (n = 20 648 [9.83%]) and cholecystectomy (n = 41 271 [7.89%]) and lowest for low anterior resection (n = 4507 [4.57%]) and pancreaticoduodenectomy (n = 1329 [2.64%]). Regarding the number of operations per surgeon, female surgeons had fewer surgical experiences for all 6 types of operations in all years after registration, except for appendectomy and cholecystectomy in the first 2 years after medical registration. The largest gender disparity for each surgical procedure was 3.17 times more procedures for male vs female surgeons for appendectomy (at 15 years after medical registration), 4.93 times for cholecystectomy (at 30-39 years), 3.65 times for right hemicolectomy (at 30-39 years), 3.02 times for distal gastrectomy (at 27-29 years), 6.75 times for low anterior resection (at 27-29 years), and 22.2 times for pancreaticoduodenectomy (at 30-39 years). Conclusions and Relevance: This cross-sectional study found that female surgeons had less surgical experience than male surgeons in Japan, and this gap tended to widen with an increase in years of experience, especially for medium- and high-difficulty operations. Gender disparity in surgical experience needs to be eliminated, so that female surgeons can advance to leadership positions.

OBJECTIVES: Surgical site infection in cardiovascular surgery had a great effect on postoperative outcomes. This study examined the current status of surgical site infection and postoperative outcomes used the registered data of the Japan Cardiovascular Surgery Database. METHODS: From the registry, we extracted 53,186 cases of thoracic cardiovascular surgery performed under median sternotomy in 2018. According to Japanese Healthcare Associated Infections Surveillance (JHAIS), patients were divided into three groups: coronary artery bypass graft (CABG) with saphenous vein graft (SVG) (SVG+ ; n = 14,246), CABG without SVG (SVG-; n = 5535), and operations other than CABG (no CABG; n = 33,405). The incidence of deep sternal wound infection, leg wound infection, hospital death, and hospitalization more than 90 days was examined. RESULTS: The incidence of deep sternal wound infection is 1.4% in all cases and 1.7% in SVG+ , 1.2% in SVG-, and 1.4% in no CABG. In deep sternal wound infection cases, incidence of hospital death was 24.7% and was higher than no infection cases. Especially, in no CABG group, incidence of hospital death was 30.1%. The long-term hospitalization rate and readmission rate within 30 days of patients with deep sternal wound infection were also high. CONCLUSIONS: The incidence of deep sternal wound infection was low, but it has not decreased. Postoperative outcomes in patients with surgical site infection were still bad.

BACKGROUND: The risk of choking increases with aging, and the number of cases of choking-induced cardiac arrest is increasing. However, few studies have examined the prognosis of choking-induced cardiac arrest. The aim of this study was to reveal the rates of survival and dependence on devices in the long term after choking-induced cardiac arrest. METHODS: We analyzed data from the Shizuoka Kokuho Database, which consists of claims data of approximately 2.2 million people, from April 2012 to September 2018. We selected patients with choking-induced cardiac arrest who received cardiopulmonary resuscitation in the hospital. Patients were excluded if they were less than 20 years old, had an upper airway tumor, received ventilation assistance, or received enteral nutrition in the month prior to cardiac arrest. The primary outcome was death, and the secondary outcomes were the rates of survival at 3-months and independence on devices. Descriptive statistics are presented and compared among age groups (20-64 years, 65-74 years, 75-84 years, 85 years and older), and survival time analysis (Kaplan-Meier method) was performed. RESULTS: In total, 268 patients were analyzed, including 26 patients in the 20-64 age group, 33 patients in the 65-74 age group, 70 patients in the 75-84 age group, and 139 patients in the ≥85 age group. The overall 3-month survival rate was 5.6% (15/268). The 3-month survival rates were 3.8% (1/26) in the 20-64 age group, 15.2% (5/33) in the 65-74 age group, 8.6% (6/70) in the 75-84 age group, and 2.2% (3/139) in the ≥85 age group. The overall 12-month survival rate was 2.6% (7/268). Of the 7 patients who survived for 12 months, 3 received ventilation management and 5 received tube or intravenous feedings at 3 months. These survivors were still receiving ventilation assistance and tube feedings in the hospital and had not been discharged at 12 months. CONCLUSIONS: The prognosis of choking-induced cardiac arrest was extremely poor when patients were not resuscitated before hospital arrival. Those who survived were mostly dependent on assistive devices. Additionally, none of the survivors dependent on assistive devices had discontinued the use of the devices at the long-term follow-up.

PURPOSE: To assess the increase in hospital costs associated with postoperative complications after lower anterior resection (LAR) for rectal cancer. METHODS: The subjects of this retrospective analysis were patients who underwent elective LAR surgery between April, 2015 and March, 2017, collected from a Japanese nationwide gastroenterological surgery registry linked to hospital-based claims data. We evaluated total and category-specific hospitalization costs based on the level of postoperative complications categorized using the Clavien-Dindo (CD) classification. We assessed the relative increase in hospital costs, adjusting for preoperative factors and hospital case volume. RESULTS: We identified 15,187 patients (mean age 66.8) treated at 884 hospitals. Overall, 71.8% had no recorded complications, whereas 7.6%, 10.8%, 9.0%, 0.6%, and 0.2% had postoperative complications of CD grades I-V, respectively. The median (25th-75th percentiles) hospital costs were $17.3 K (16.1-19.3) for the no-complications group, and $19.1 K (17.3-22.2), $21.0 K (18.5-25.0), $27.4 K (22.4-33.9), $41.8 K (291-618), and $22.7 K (183-421) for the CD grades I-V complication groups, respectively. The multivariable model identified that complications of CD grades I-V were associated with 11%, 21%, 61%, 142%, and 70% increases in in-hospital costs compared with no complications. CONCLUSIONS: Postoperative complications and their severity are strongly associated with increased hospital costs and health-care resource utilization. Implementing strategies to prevent postoperative complications will improve patients' clinical outcomes and reduce hospital care costs substantially.

This study aimed to evaluate the effect of the asthma care program available under the Universal Coverage Scheme (UCS) in Thailand on hospital admissions per 100,000 population, its regional and seasonal variation, readmission within 28 days, and the asthma-specific fatality rate of patients aged 0-29 years in 2009-2016 compared with those in 2007-2008. A retrospective study was conducted using data sources from the UCS register and in-patient databases from the National Health Security Office (NHSO), Thailand. Hospital admissions per 100,000 population was the highest among those aged 0-4 years, but the trends decreased from 470.8 to 288.1 per 100,000 population in 2010-2014. The hospital admission rates were high in Southern Thailand and common in rainy seasons. The readmission rates within 28 days slightly decreased in all age groups in 2016 compared to those in 2007. The case fatality rate of patients aged 20-29 years decreased from 0.40% in 2007 to 0.34% in 2016. The readmission rate within 28 days and case fatality rate were the highest in patients aged 20-29 years. In conclusion, the asthma hospital admission, readmission, and case fatality rates declined over time along with the investment in the asthma care program under the UCS in Thailand. The highest hospital admission rates in patients aged 0-4 years and the readmission and case fatality rates in patients aged 20-29 years should be given more attention. Recordings of individual service utilization data in asthma patients, including quality of care provided, should be monitored to improve the asthma care system.

OBJECTIVES: To assess the applicability of Electronic Frailty Index (eFI) and Hospital Frailty Risk Score (HFRS) algorithms to Japanese administrative claims data and to evaluate their association with long-term outcomes. STUDY DESIGN AND SETTING: A cohort study using a regional government administrative healthcare and long-term care (LTC) claims database in Japan 2014-18. PARTICIPANTS: Plan enrollees aged ≥50 years. METHODS: We applied the two algorithms to the cohort and assessed the scores' distributions alongside enrollees' 4-year mortality and initiation of government-supported LTC. Using Cox regression and Fine-Gray models, we evaluated the association between frailty scores and outcomes as well as the models' discriminatory ability. RESULTS: Among 827,744 enrollees, 42.8% were categorised by eFI as fit, 31.2% mild, 17.5% moderate and 8.5% severe. For HFRS, 73.0% were low, 24.3% intermediate and 2.7% high risk; 35 of 36 predictors for eFI, and 92 of 109 codes originally used for HFRS were available in the Japanese system. Relative to the lowest frailty group, the highest frailty group had hazard ratios [95% confidence interval (CI)] of 2.09 (1.98-2.21) for mortality and 2.45 (2.28-2.63) for LTC for eFI; those for HFRS were 3.79 (3.56-4.03) and 3.31 (2.87-3.82), respectively. The area under the receiver operating characteristics curves for the unadjusted model at 48 months was 0.68 for death and 0.68 for LTC for eFI, and 0.73 and 0.70, respectively, for HFRS. CONCLUSIONS: The frailty algorithms were applicable to the Japanese system and could contribute to the identifications of enrollees at risk of long-term mortality or LTC use.

Background and Aim: In Japan, the actual number of stoma constructions and stoma closures is not known. The aim of this study was to conduct a survey to determine the number of gastrointestinal stoma constructions and closures in Japan. Methods: Enrolled participants comprised patients undergoing selected gastrointestinal surgeries who were recorded in the National Clinical Database. This database uses the "Common Items for Gastrointestinal Surgeons." These procedures were formulated by the Japanese Society of Gastroenterological Surgery during 2013-2018. Results: According to the National Clinical Database, a total of 154,323 gastrointestinal stomas were constructed between January 1, 2013 and December 31, 2018. By procedure, there were 78,723 cases of stoma construction, 39,653 of abdominoperineal resection, 2470 total pelvic exenteration procedures, and 33,572 Hartmann's procedures. The ratio of stoma closures to stoma constructions increased annually in patients under 70 y of age but not in older patients. Approximately 35% of total colectomies, 60% of proctocolectomies, and 20% of low anterior resections were accompanied by stoma construction. The number of patients with rectal cancer who underwent colostomy increased gradually during the study period and the number who underwent stoma construction increased among older patients. Conclusion: The number of cases of gastrointestinal stoma construction has increased gradually in Japan, and the proportion of older patients is increasing each year. The purposes and surgical techniques for stoma construction are diverse and are expected to increase in Japan, a super-aged society.

BACKGROUND AND PURPOSE: The spread of COVID-19 has restricted the delivery of standard medical care to surgical patients dramatically. Surgical triage is performed by considering the type of disease, its severity, the urgency for surgery, and the condition of the patient, in addition to the scale of infectious outbreaks in the region. The purpose of this study was to evaluate the impact of the COVID-19 pandemic on the number of surgical procedures performed and whether the effects were more prominent during certain periods of widespread infection and in the affected regions. METHODS: We selected 20 of the most common procedures from each surgical field and compared the weekly numbers of each operation performed in 2020 with the respective numbers in 2018 and 2019, as recorded in the National Clinical Database (NCD). The surgical status during the COVID-19 pandemic as well as the relationship between surgical volume and the degree of regional infection were analyzed extensively. RESULTS: The rate of decline in surgery was at most 10-15%. Although the numbers of most oncological and cardiovascular procedures decreased in 2020, there was no significant change in the numbers of pancreaticoduodenectomy and aortic replacement procedures performed in the same period. CONCLUSION: The numbers of most surgical procedures decreased in 2020 as a result of the COVID-19 pandemic; however, the precise impact of surgical triage on decrease in detection of disease warrants further investigation.

BACKGROUND: Hemoglobin A1c (HbA1c) levels are routinely measured during health check-ups and are used as an indicator of glycemic control in Japan. However, only a few studies have followed up individuals to assess the risk of diabetes development and worsening based on HbA1c screening results. This study evaluated the relationship between HbA1c screening results and the risk of diabetes development and worsening. METHODS: Data were collected from the Shizuoka Kokuho Database, a Japanese administrative claims database of insured individuals aged > 40 years. We included individuals available for follow-up from April 2012 to March 2018 who had not received any diabetes treatment before March 2014. HbA1c screening results were categorized into 4 groups based on the HbA1c levels at the 2012 and 2013 health check-ups: group A, those whose HbA1c levels were < 6.5% in 2012 and 2013; group B, those whose HbA1c levels > 6.5% in 2012 but < 6.5% in 2013; group C, those whose HbA1c levels were > 6.5% in 2012 and 2013; and group D, those whose HbA1c levels were < 6.5% in 2012 and > 6.5% in 2013. Logistic regression models were used to analyze diabetes development and worsening, defined as the initiation of diabetes treatment by March 2018 and the use of injection drugs by participants who initiated diabetes treatment by March 2018. RESULTS: Overall, 137,852 individuals were analyzed. After adjusting for covariates, compared with group A, group B was more likely to initiate treatment within 4 years (odds ratio: 22.64; 95% confidence interval: 14.66-34.99). In patients who initiated diabetes treatment by March 2018, injection drugs were less likely used by group D than by group A (odds ratio: 0.28; 95% confidence interval: 0.12-0.61). CONCLUSIONS: Our study suggests that although HbA1c levels measured during health check-ups were correlated with the risk of diabetes development and worsening, HbA1c levels in a single year may not necessarily provide sufficient information to consider these future risks.

BACKGROUND: Robotic gastrectomy (RG) has increased since being covered by universal health insurance in 2018. However, to ensure patient safety the operating surgeon and facility must meet specific requirements. We aimed to determine whether RG has been safely implemented under the requirements for universal health insurance in Japan. METHODS: Data of consecutive patients with primary gastric cancer who underwent minimally invasive total or distal gastrectomy-performed by a surgeon certified by the Japan Society for Endoscopic Surgery (JSES) endoscopic surgical skill qualification system (ESSQS) between October 2018 and December 2019-were extracted from the gastrointestinal surgery section of the National Clinical Database (NCD). The primary outcome was morbidity over Clavien-Dindo classification grade IIIa. Patient demographics and hospital volume were matched between RG and laparoscopic gastrectomy (LG) using propensity score-matched analysis (PSM), and the short-term outcomes of RG and LG were compared. RESULTS: After PSM, 2671 patients who underwent RG and 2671 who underwent LG were retrieved (from a total of 9881), and the standardized difference of all the confounding factors reduced to 0.07 or less. Morbidity rates did not differ between the RG and LG patients (RG, 4.9% vs. LG, 3.9%; p = 0.084). No difference was observed in 30-day mortality (RG, 0.2% vs. LG, 0.1%; p = 0.754). The reoperation rate was greater following RG (RG, 2.2% vs. LG, 1.2%; p = 0.004); however, the duration of postoperative hospitalization was shorter (RG, 10 [8-13] days vs. LG, 11 [9-14] days; p < 0.001). CONCLUSIONS: Insurance-covered RG has been safely implemented nationwide.

Background: Esophagectomy followed by gastric conduit reconstruction is a standard surgical procedure for esophageal cancer. However, there is no evidence of the superiority or inferiority of the posterior mediastinal (PM) versus the retrosternal (RS) reconstruction route with regard to short-term outcomes after esophagectomy. We aimed to elucidate whether the reconstruction route can affect the short-term outcomes after esophagectomy followed by gastric conduit reconstruction. Methods: We reviewed the clinical data of patients who underwent esophagectomy between 2016 and 2018 from the Japanese National Clinical Database. This study included 9786 patients who underwent gastric conduit reconstruction through the PM or RS route with cervical anastomosis. Results: Of the 9786 patients analyzed, 3478 and 6308 underwent gastric conduit reconstruction thorough the PM and RS routes, respectively. The incidence of anastomotic leak and surgical site infection (SSI) was significantly lower in the PM group than in the RS group (11.7% vs 13.8%, P = .005 and 8.4% vs 14.9%, P < .001, respectively), while the incidence of pneumonia was higher in the PM group (13.7% vs 12.2%, P = .040). Generalized estimating equation logistic regression analysis revealed a higher risk of anastomotic leak and SSI (odds ratio [OR], 1.32; 95% confidence interval [CI], 1.15-1.51; P < .001 and OR, 2.06; 95% CI, 1.78-2.38; P < .001, respectively) and a lower risk of pneumonia (OR, 0.86; 95% CI, 0.75-0.98; P = .028) in the RS group than in the PM group. Conclusion: The findings of this study will help surgeons to design the reconstruction route following esophagectomy.

Background: We aimed to present the 2019 annual report of the gastroenterological section of the National Clinical Database (NCD). Methods: We reviewed 609,589 cases recorded in 2019 and 5,029,764 cases registered from 2011 to 2019 for the 115 selected gastroenterological surgical procedures. Results: The main features of gastroenterological surgery in Japan were similar to those described in the 2018 annual report, namely, that 1) operative numbers gradually increased in all procedures, except gastrectomy and hepatectomy, which decreased in these years; 2) in all eight major gastroenterological surgeries, the age distribution tended toward older patients; 3) the morbidity of esophagectomy, hepatectomy, and pancreaticoduodenectomy increased, but mortality was minimized in all procedures; 4) all eight major gastroenterological procedures have increasingly been performed under laparoscopy; and 5) board-certified surgeons were increasingly involved. These trends in recent years were more prominent in 2019. Conclusions: Thanks to the continuous cooperation and dedication of the surgeons, medical staff, and surgical clinical reviewers who registered the clinical data into the NCD, it is possible to understand the comprehensive landscape of surgery in Japan and to disclose new evidence in this field. The Japanese Society of Gastroenterological Surgery will continue to promote the value of this database and encourage the use of feedback and clinical studies using the NCD, now and in the future. Generating further approaches to surgical quality improvement are important directions for future research.

PURPOSE: We investigated the association between the number of certified general thoracic surgeons (GTSs) and the mortality after lung cancer surgery, based on the data from the National Clinical Database (NCD). METHODS: We analyzed the characteristics and operative and postoperative data of 120,946 patients who underwent lung cancer surgery in one of the 905 hospitals in Japan. The number of GTSs in each hospital was categorized as 0, 1-2, or 3 or more. Multivariable analysis was applied to adjust the patients' preoperative risk factors, as identified in a previous study. We calculated 95% confidence intervals (CI) for the mortality rate based on the odds ratios (ORs). RESULTS: The patients' characteristics were distributed almost uniformly regardless of the number of GTSs. Crude mortality according to the number of GTSs of 0, 1-2, or 3 or more was 0.9%, 0.8%, and 0.7%, respectively (p = 0.03). However, after adjustment, the ORs for 1-2 and 3 or more GTSs (reference: 0) were 0.86 (p = 0.23, 95% CI: 0.67-1.10) and 0.84 (p = 0.18, 95% CI: 0.64-1.09), respectively. The number of GTSs did not have a significant association with mortality. Similar results were observed for patients in the lobectomy cohort. CONCLUSION: Low surgical mortality was consistent, regardless of the number of GTSs in each hospital.

OBJECTIVES: There have been limited data available regarding aortic arch replacement in dialysis patients. The purpose of this study was to examine real-world data and to determine the impact of preoperative dialysis status and other risks on surgical aortic arch replacement using the Japan Cardiovascular Surgery Database. METHODS: A total of 5044 patients who underwent elective, isolated aortic arch replacement using antegrade cerebral perfusion during 2014-2017 were eligible for the study. Of these, 89 patients received haemodialysis preoperatively. The patients were divided into 6 groups according to their preoperative estimated glomerular filtration rate and dialysis status for comparison. Preoperative and postoperative data were examined using a multivariable regression model. RESULTS: The overall surgical mortality rates of non-Chronic Kidney Disease (CKD) (estimated glomerular filtration rate >60 ml/min/1.73 m2), stage 3A, stage 3B, stage 4, stage 5 CKD and dialysis patients were 2.6%, 3.1%, 6.8%, 11.6%, 16.7% and 13.5%, respectively. After risk adjustment, dialysis was shown to be strongly associated with surgical mortality (odds ratio 4.39 and 95% confidence interval 2.22-8.72) and have a trend to be associated with postoperative stroke (odds ratio 2.02, 95% confidence interval 1.00-4.10, P = 0.051) when compared to the non-CKD group. As predictors of mortality, male sex, peripheral arterial disease, preoperative liver dysfunction and impaired left ventricular function were identified. CONCLUSIONS: The Japanese nationwide database revealed the outcomes of aortic arch replacement in dialysis patients. Appropriate counselling and an alternative strategy should be considered for such patients with multiple risks for mortality.

OBJECTIVE: The incidence of type 1 diabetes mellitus (T1DM) and hypothyroidism as immune-related adverse events (irAEs) after programmed cell death-1 inhibitor (PD-1i) administration has not yet been sufficiently evaluated in a real clinical setting. To assess the incidence of T1DM and hypothyroidism among PD-1is and to identify the risk factors associated with hypothyroidism using a large claims database. METHODS: This cohort study used the Shizuoka Kokuho database in Japan from 2012 to 2018, including approximately 2.2 million people. We enrolled 695 PD-1i-treated patients. T1DM and hypothyroidism as irAEs were identified using International Classification of Diseases 10th Revision and Anatomical Therapeutic Chemical classification codes. Risk factors for hypothyroidism were explored using the multivariable Fine and Gray regression model after adjusting for age group and sex, treating death as a competing risk. RESULTS: The cumulative incidences of T1DM and hypothyroidism were 0.3% and 8.3%, respectively. We described the detailed onset timing of irAEs in patients with T1DM and hypothyroidism; hypothyroidism was observed evenly within 1 year of the PD-1i prescription. Sex and certain cancer types, such as lung and urothelial cancers, were significantly associated with subdistribution hazard ratio (sHR) (female: sHR, 2.04 [95% CI, 1.20-3.47]; lung cancer: sHR, 0.55 [95% CI, 0.32-0.95]; and urothelial carcinoma: sHR, 2.40 [95% CI, 1.05-5.49]). CONCLUSION: The incidence of T1DM and hypothyroidism as irAEs and associated risk factors identified in this analysis were comparable to those found in previous studies. The use of a large claims database to detect irAEs, such as T1DM and hypothyroidism, may lead to safer use of PD-1is.

PURPOSE: This study compared the quality of healthcare before and after implementation of a policy restructuring the healthcare delivery system and estimated the impact of centralization. METHODS: We used the National Clinical Database to study patients undergoing esophagectomies from 2011 to 2016. We compared the effect of centralization based on the patient background, surgical mortality, and year of surgery. Difference-in-difference methods based on the generalized estimating equation logistic regression model were used for before-and-after comparisons after adjusting for patient-level expected surgical mortality. RESULTS: In total, 34,640 cases were identified. More cases with risk factors were noted in ultra-low-volume hospitals, where 38.4% of cases in underpopulated areas were treated, than in higher volume facilities, and the operative mortality, readmission within 30 days and length of stay were worse among patients treated in these hospitals. In centralized prefectures, the number of cases per hospital increased over time (7.2 in 2011 to 9.5 in 2016) while the crude operative mortality tended to decrease (3.4% in 2011 to 1.8% in 2016). The difference-in-difference estimator was 0.856 (95% confidence interval: 0.639-1.147, p = 0.298). CONCLUSION: The centralization of ultra-low-volume hospitals did not lead to a deterioration in the quality of care but rather an improving trend.

BACKGROUND: It is unclear to what extent a board certification system and implementation of clinical guidelines improves the quality of hepatectomy. METHODS: A web-based questionnaire survey was administered to departments registered with the National Clinical Database (NCD) in Japan between 1 October 2014 and 31 January 2015. Quality indicators (QIs), including affiliations with academic societies, numbers of board-certified doctors affiliated with each institute, and adherence to clinical practice guidelines for hepatocellular carcinoma, were evaluated by calculating risk-adjusted odds ratios (AORs) for 90-day postoperative mortality of patients who had undergone hepatectomy in 2013 and 2014. RESULTS: Of 1255 departments that had registered at least one hepatectomy in NCD, 592 departments, performing 8601 hepatectomies in total, responded to the questionnaire. AORs were significantly lower in departments that were certified as training hospitals by the Japanese Society of Gastroenterological Society, Japanese Society of Hepato-Biliary Pancreatic Surgery (JSHBPS), and Japan Society of Hepatology than in non-certified departments. Affiliation of three or more JSHBPS-certified experts or instructors with an institution also contributed to low AORs. None of the QIs regarding implementation of guidelines significantly impacted on the AOR. CONCLUSIONS: QI measurements may improve quality of post-hepatectomy outcomes in Japan.

PURPOSE: The objective of our study was to develop a clinical prediction model for prolonged air leak (PAL) after lobectomy for lung cancer using preoperative variables in a large patient dataset from the National Clinical Database (NCD) in Japan. METHODS: The preoperative characteristics of 57,532 and 30,967 patients who had undergone standard lobectomy for lung cancer were derived from the 2014 to 2015 and 2016 NCD datasets, respectively. PAL was defined as air leak persisting ≥ 7 days postoperatively or requiring postoperative interventional treatment, such as pleurodesis or reoperation. Risk models were developed from the 2014 to 2015 dataset and validated using the 2016 dataset. When performing model derivation, the least absolute shrinkage and selection operator (LASSO) method were applied for parameter selection. RESULTS: The rate of PAL was 4.5% in 2014-2015 and 5.3% in 2016. The age, sex, body mass index, comorbid interstitial pneumonia, smoking habits, forced expiratory volume in 1 s, tumor histology, multiple lung cancer, and tumor location were selected as important variables for PAL. Our risk model for predicting PAL was fair with a concordance index of 0.6895. CONCLUSION: The LASSO-based risk model for PAL after lobectomy provided important preoperative variables for PAL and risk weighting for each variable.

BACKGROUND: Few reports about surgical outcomes in malignant pleural mesothelioma (MPM) were based on reliable nationwide databases. Here we analyzed the incidence, surgical outcome, and operative risk factors using Japanese nationwide database. METHODS: Characteristics and perioperative data from 622 patients who underwent curative-intent surgery for MPM between January 2014 and December 2017 were recorded from National Clinical Database of Japan. We analyzed the incidence, surgical outcomes, and risk factors for surgical complications after two surgical procedures (extrapleural pneumonectomy, EPP; and pleurectomy/decortication, P/D). RESULTS: During 4 years, EPP was performed in 279 patients and P/D in 343. EPP was more frequently performed in less-MPM-experienced institutions, while P/D was more frequently performed in well-MPM-experienced institutions (P < .001), especially in high-volume centers with more than 10 cases during this period. P/D was more frequently performed, especially in high-volume centers. The morbidity rates were 45.2% in EPP and 35.9% in P/D. Heart failure and pneumonia were most frequent in EPP, while prolonged air leakage was most frequent in P/D. Thirty-day- and in-hospital mortality rates were 1.1% and 3.2% (EPP) and 1.2% and 3.2% (P/D), respectively. Regression analyses revealed that higher age (>65 years) was associated with operative complications in EPP (odds ratio, OR: 3.56 [1.26-8.56]), whereas no risk factor was observed in P/D. CONCLUSIONS: In Japanese nationwide annual database, P/D was more frequently performed, especially in high-volume centers. Morbidity was higher in EPP than P/D; however, the mortality rates were quite low in Japan regardless surgical procedures.

The National Clinical Database (NCD) of Japan grew rapidly, harvesting over 11 million cases of data between 2011 and 2018 from more than 5000 facilities. This is the Report of the NCD based upon gastrointestinal surgery information in 4 420 175 cases from 2011 to 2018. More than 70% of all gastrointestinal surgeries were performed at certified institutions, and the percentage of surgeries performed at certified institutions was particularly high for the esophagus (93.8% in 2018), liver (89.4%), pancreas (91.3%), and spleen (86.9%). Also, more than 70% of the surgeries were performed with the participation of the board-certified surgeon. As the patients have been getting older, the morbidities have been increasing. However, the mortalities have been kept at a low level. The rates of endoscopic surgery have been increasing year by year, especially high in low anterior resection (67.0%) and esophagectomy (61.0%). Nationwide, this database is surely expecting to ensure the quality of board certification system and surgical outcomes in gastroenterological surgery.

BACKGROUND: The high operative mortality rate after hepatopancreatoduodenectomy (HPD) is still a major issue. The present study explored why operative mortality differs significantly due to hospital volume. METHOD: Surgical case data were extracted from the National Clinical Database (NCD) in Japan from 2011 to 2014. Surgical procedures were categorized as major (≥2 sections) and minor (<2 sections) hepatectomy. Hospitals were categorized according to the certification system by the Japanese Society of Hepato-Biliary-Pancreatic Surgery (JSHBPS) based on the number of major hepato-biliary-pancreatic surgeries performed per year. The FTR rate was defined as death in a patient with at least one postoperative complication. RESULTS: A total of 422 patients who underwent HPD were analyzed. The operative mortality rates in board-certified A training institutions, board-certified B training institutions, and non-certified institution were 7.2%, 11.6%, and 21.4%, respectively. Multiple logistic regression showed that certified A institutions, major hepatectomy, and blood transfusion were the predictors of operative mortality. Failure to rescue rates were lowest in certified A institutions (9.3%, 17.0%, and 33.3% in certified A, certified B, and non-certified, respectively). CONCLUSIONS: To reduce operative mortality after HPD, further centralization of this procedure is desirable. Future studies should clarify specific ways to improve the failure-to-rescue rates in certified institutions.

Aim: Appendicitis is divided into two categories: complicated appendicitis (CA) and uncomplicated appendicitis (UA). In pediatric patients with CA, the use of interval appendectomy (IA), which is non-operative management followed by elective surgery, has decreased the number of postoperative complications. Before discussing the merit of IA for adult patients, we need to clarify whether the frequency and seriousness of the complication rate after emergency surgery is higher for CA than for UA. Methods: This retrospective cohort study included adult patients who underwent appendectomy and who were registered in the National Clinical Database (NCD) from 2014 to 2016. Patients with CA who underwent emergency appendectomy comprised the CA group. Patients with UA comprised the UA group. Patients with chronic or recurrent appendicitis who underwent elective appendectomy comprised the elective appendectomy (EA) group. Primary outcomes were all morbidity, serious morbidity, and mortality within 30 days after appendectomy. Results: We included 109 256 patients in the study: 14 798 CA, 86 876 UA, and 7582 EA patients. Compared with the UA group, the rates of all morbidity, serious morbidity, and mortality were significantly higher in the CA group. All morbidity, serious morbidity, and mortality rates were significantly lower in the EA group than in the other two groups. Conclusions: We confirmed that emergency surgery for CA places the patient at relatively higher risk. We also showed that the risk associated with EA is significantly lower than that for the other methods.

The traditional anion gap (AG) equation is widely used, but its misdiagnosis in end-stage kidney disease (ESKD) patients has not been investigated fully. Diagnostic accuracy to detect high AG was cross-sectionally evaluated using 3 AG equations in 1733 ESKD patients with an eGFR less than 15 mL/min/1.73 m2. The prevalence of high AG was 67.9%, 92.1% and 97.4% by the traditional, albumin-adjusted AG (aAG) and full AG equations, respectively. The sensitivity, specificity, accuracy and Kappa coefficient obtained with the traditional AG vs aAG equation were 0.70 vs 0.94, 0.98 vs 0.93, 0.7 vs 0.94, and 0.103 vs 0.44, respectively. Next, we created a subcohort comprising only patients with high full AG and investigated how the traditional AG equation leads to misdiagnoses. Multivariable-adjusted regression analysis in 1688 patients revealed that independent factors associated with a false-negative AG diagnosis were ARB use, eGFR, blood leukocyte count, serum chloride, bicarbonate, ionized calcium, potassium, albumin and phosphate. 93.2% of our subcohort prescribed any of RAAS inhibitors, Loop diuretics or Alkali which could increase either serum chloride or bicarbonate. Frequent use of these possible AG-reducing medications may conceal high AG state in patients with ESKD unless they have incidental inflammation which may increase AG value.

BACKGROUND: Smoking is a known risk factor for postoperative mortality and morbidity. However, the significance of cumulative smoking dose in preoperative risk assessment has not been established. We examined the influence of preoperative cumulative smoking dose on surgical outcomes after lobectomy for primary lung cancer. METHODS: A total of 80,989 patients with primary lung cancer undergoing lobectomy from 2014 to 2016 were enrolled. Preoperative cumulative smoking dose was categorized by pack-years (PY): Non-smokers, PY = 0; Light smokers, 0 < PY < 10; Moderate smokers, 10 ≤ PY < 30; and Heavy smokers, 30 ≤ PY. The risk of short-term outcomes was assessed according to PY by multivariable analysis adjusted for other covariates. RESULTS: Postoperative 30-day mortality, as well as pulmonary, cardiovascular, and infectious complications, increased with preoperative PY. Multivariable analysis revealed the odds ratios (ORs) for postoperative mortality compared with non-smokers were 1.76 for light smokers (p=0.044), 1.60 for moderate smokers (p=0.026), and 1.73 for heavy smokers (p=0.003). The ORs for pulmonary complications compared with non-smokers were 1.20 for light smokers (p= 0.022), 1.40 for moderate smokers (p<0.001), and 1.72 for heavy smokers (p<0.001). Heavy smokers had a significantly increased risk of postoperative cardiovascular (OR, 1.26; p=0.002) and infectious complications (OR, 1.39; p=0.007) compared with non-smokers. CONCLUSIONS: The risk of mortality and morbidity after lung resection could be predicted according to preoperative cumulative smoking dose. These findings contribute to the development of strategies in perioperative management of lung resection patients.

The National Clinical Database (NCD) of Japan was established in 2010 with the board certification system. A joint committee of 16 gastroenterological surgery database-affiliated organizations has been nurturing this nationwide database and utilizing its data for various analyses. Stepwise board certification systems have been validated by the NCD and are used to improve the surgical outcomes of patients. The use of risk calculators based on risk models can be particularly helpful for establishing appropriate and less invasive surgical treatments for individual patients. Data obtained from the NCD reflect current developments in the surgical approaches used in hospitals, which have progressed from open surgery to endoscopic and robot-assisted procedures. An investigation of the data acquired by the NCD could answer some relevant clinical questions and lead to better surgical management of patients. Furthermore, excellent surgical outcomes can be achieved through international comparisons of the national databases worldwide. This review examines what we have learned from the NCD of gastroenterological surgery and discusses what future developments we can expect.

BACKGROUND: Descriptive analyses of 2009-2016 were performed using the data of the Universal Coverage Scheme (UCS) which covers nearly 70 percent of the Thai population. The analyses described the time and geographical trends of nationwide admission rates of type 2 diabetes mellitus (T2DM) and its complications, including chronic kidney disease (CKD), myocardial infarction, cerebrovascular diseases, retinopathy, cataract, and diabetic foot amputation. METHODS AND FINDINGS: The database of T2DM patients aged 15-100 years who were admitted between 2009 and 2016 under the UCS and that of the UCS population were retrieved for the analyses. The admitted cases of T2DM were extracted from the database using disease codes of principal and secondary diagnoses defined by the International Classification of Diseases 9th and 10th Revisions. The T2DM admission rates in 2009-2016 were the number of admissions divided by the number of the UCS population. The standardized admission rates (SARs)were further estimated in contrast to the expected number of admissions considering age and sex composition of the UCS population in each region. A linearly increased trend was found in T2DM admission rates from 2009 to 2016. Female admission rates were persistently higher than that of males. In 2016, an increase in the T2DM admission rates was observed among the older ages relative to that in 2009. Although the SARs of T2DM were generally higher in Bangkok and central regions in 2009, except that with CKD and foot amputation which had higher trends in northeastern regions, the geographical inequalities were fairly reduced by 2016. CONCLUSION: Admission rates of T2DM and its major complications increased in Thailand from 2009 to 2016. Although the overall geographical inequalities in the SARs of T2DM were reduced in the country, further efforts are required to improve the health system and policies focusing on risk factors and regions to manage the increasing T2DM.

AIMS/INTRODUCTION: Increased incidence of hospitalization for heart failure (HHF) among patients with diabetes is increasingly being reported. We investigated the incidence of adverse cardiovascular events including HHF among patients with type 2 diabetes mellitus, and the potential clinical improvement with sodium-glucose cotransporter 2 inhibitors (SGLT2i) using a contemporary administrative claims database from a large governmental district of Japan. MATERIALS AND METHODS: We included initiators of any oral glucose-lowering drugs between 2013 and 2018. We estimated the 5-year cumulative incidence of hospitalization for HF, myocardial infarction and stroke, treating death as a competing risk. We evaluated the possible impact of introducing SGLT2i to the potential recipients of the drug, using the inclusion criteria from Empagliflozin Cardiovascular Outcome Event Trial in Type 2 Diabetes Mellitus Patients (EMPA-REG OUTCOME) and Dapagliflozin Effect on Cardiovascular Events-Thrombolysis in Myocardial Infarction 58 (DECLARE-TIMI 58) trials, assuming the same risk reduction as theirs. RESULTS: Among 23,340 drug initiators (54.0% men, and 6.4% aged >85 years), the 5-year cumulative incidence was 5.4% (95% confidence interval 4.9-5.9%) for HHF, 1.9% (95% confidence interval 1.7-2.2%) for myocardial infarction admission and 6.1% (95% confidence interval 5.7-6.6%) for stroke admission. Among 6,192 patients with laboratory test data, 651 (10.5%) and 2,680 (43.3%) patients met the EMPA-REG-like and DECLARE-like criteria, respectively. The 5-year cumulative incidence among the 2,849 patients meeting either of the criteria was estimated to decrease from 97.1 to 75.6 events through 75% adoption of SGLT2i. CONCLUSIONS: The incidence of HHF was similar to that of stroke. A significant portion of our cohort met the inclusion criteria for major randomized clinical trials for SGLT2i, and estimated reduction in the HHF events was substantial.

PURPOSE: As the number of cases of early lung cancer in Japan grows, an analysis of the present status of surgical treatments for clinical stage IA lung cancer using a nationwide database with web-based data entry is warranted. METHODS: The operative and perioperative data from 47,921 patients who underwent surgery for clinical stage IA lung cancer in 2014 and 2015 were obtained from the National Clinical Database (NCD) of Japan. Clinicopathological characteristics, surgical procedure, mortality, and morbidity were analyzed, and thoracotomy and video-assisted thoracic surgery (VATS) were compared. RESULTS: The patients comprised 27,208 men (56.8%) and 20,713 women (43.2%); mean age, 69.3 years. Lobectomy was performed in 64.8%, segmentectomy in 15.2%, and wedge resection in 19.8%. The surgical procedures were thoracotomy in 12,194 patients (25.4%) and a minimally invasive approach (MIA) in 35,727 patients (74.6%). MIA was divided into VATS + mini-thoracotomy (n = 13,422, 28.0%) and complete VATS (n = 22,305, 46.5%). The overall postoperative mortality rate was 0.4%, being significantly lower in the MIA group than in the thoracotomy group (0.3% vs 0.8%, P < 0.001). CONCLUSIONS: Our analysis of data from the NCD indicates that MIA has become the new standard treatment for clinical stage IA lung cancer.

BACKGROUND: Ischemic papillary muscle rupture (PMR) is a catastrophic complication following acute myocardial infarction (AMI). We evaluated early outcomes of PMR by using data from the Japan Cardiovascular Surgery Database, a nationwide Japanese registry. METHODS: We retrospectively analyzed data from 196 patients diagnosed with PMR following AMI in Japan between January 2014 and December 2017. Risk factors for operative mortality and severe complications following mitral valve surgery were analyzed. RESULTS: The 30-day and hospital mortality rates were 20% and 26%, respectively. Chronic hemodialysis, abrupt rupture after AMI, resuscitation before surgery, and preoperative venoarterial extracorporeal membrane oxygenation were associated with mortality. Mitral valve replacement was chosen mainly (90%) for surgical correction of mitral regurgitation in these patients. There was no significant difference in short-term outcomes between mitral valve replacement versus mitral valve repair, despite non-matched characteristics in background between the treatment groups. Concomitant coronary artery bypass grafting had no impact on short-term outcomes. CONCLUSIONS: Information derived from the nationwide database of patients with AMI-associated PMR show that PMR is a rare condition in the modern era. However, PMR is a severe disease with a mortality rate as high as 26%. The severity of the condition is associated with the risk for poor outcomes.

OBJECTIVE: To elucidate the association between preoperative hemoglobin A1c (HbA1c) levels and short-term outcomes after oncologic esophagectomy. SUMMARY BACKGROUND DATA: Although diabetes mellitus (DM) is associated with an increased risk of postoperative morbidity in several types of surgery, the association of DM with short-term outcomes after esophagectomy has shown conflicting results. METHODS: We analyzed 15801 patients who underwent oncologic esophagectomy between 2015 and 2017 from the National Clinical Database. We evaluated the associations between preoperative HbA1c levels and short-term outcomes, using multivariable logistic regression and restricted cubic spline models. RESULTS: The cohort included 12074, 1361, 1097, 909, and 360 patients with HbA1c levels of ≤5.9%, 6.0%-6.4%, 6.5%-6.9%, 7.0%-7.9%, and ≥8.0%, respectively. There were value-dependent associations between HbA1c values and odds ratios (ORs) for anastomotic leakage (AL), surgical site infections (SSIs), pneumonia, and composite outcomes. Compared with the HbA1c category of ≤5.9%, the categories of 7.0%-7.9% and ≥8.0% were at higher risk for AL (P <0.001 and 0.031, respectively), the category of ≥8.0% was at higher risk for SSIs (P = 0.001), the categories of 6.5%-6.9% and 7.0%-7.9% were at higher risk for pneumonia (P = 0.016 and 0.002, respectively), and the categories of 7.0-7.9 and ≥ 8.0% were at higher risk for composite outcomes (P < 0.001 and 0.001, respectively). CONCLUSIONS: Preoperative HbA1c levels are associated with the risk of postoperative complications following esophagectomy, and the threshold values differed among the outcomes. Preoperative HbA1c is useful in predicting the risk of postoperative complications.

Aim: This study aimed to evaluate the association between surgeons certified via the Endoscopic Surgical Skill Qualification System (ESSQS) of the Japan Society for Endoscopic Surgery (JSES) and surgical outcomes of laparoscopic distal gastrectomy (LDG) and laparoscopic low anterior resection (LLAR). Methods: Japanese National Clinical Database data on the patients undergoing LDG and LLAR between 2014-2016 were analyzed retrospectively. The proportion of cases performed by ESSQS-certified surgeons was calculated for each procedure, and clinicopathological factors with or without participation of ESSQS-certified surgeons as an operator were assessed. Then, effects of operations performed by ESSQS-certified surgeons on short-term patient outcomes were analyzed using generalized estimating equations logistic regression analysis. Results: There were 110 610 and 65 717 patients who underwent LDG and LLAR, respectively. The operations performed by ESSQS-certified surgeons in each procedure totaled 28 467 (35.3%) and 12 866 (31.2%), respectively. A multivariable logistic regression model showed that odds ratios of mortality for LDG and LLAR performed by ESSQS-certified surgeons were 0.774 (95% CI, 0.566-1.060, P = 0.108) and 0.977 (0.591-1.301, P = 0.514), respectively. Odds ratios for secondary endpoints of anastomotic leakage in LDG and LLAR performed by ESSQS-certified surgeons were 0.835 (95% CI, 0.723-0.964, P = 0.014) and 0.929 (0.860-1.003, P = 0.059), respectively, whereas that of ileus/bowel obstruction for LLAR performed by ESSQS-certified surgeons was 1.265 (1.132-1.415, P < 0.001). There were no significant associations between the two operations performed by ESSQS-certified surgeons and other factors such as mortality and overall complications. Conclusions: ESSQS certification did not affect postoperative mortality following LDG and LLAR, but annual experience of laparoscopic surgery was associated with it. ESSQS certification may contribute to favorable outcomes regarding anastomotic leakage following LDG and LLAR.

BACKGROUND: Despite interest in surgeon and hospital volume effects on total gastrectomy (TG), clinical significance has not been confirmed in a large-scale population. This study aimed at clarifying the association of surgeon and hospital volume on postoperative mortality after TG for gastric cancer among Japanese patients in National Clinical Database (NCD). METHODS: Between 2011 and 2015, we retrospectively extracted data on TG for gastric cancer from the NCD. The primary outcome was operative mortality. We divided surgeon volume as the number of TGs performed by a patient's surgeon in the previous year: S1 (0-2 cases), S2 (3-9), S3 (10-25), S4 (26-79) and hospital volume by the number of TGs performed in the previous year: H1 (0-11 cases), H2 (12-26), H3 (27-146). We calculated the 95% confidence interval (CI) for the mortality rate based on odds ratios (OR) estimated from a hierarchical logistic regression model. RESULTS: We analyzed 71,307 patients at 2051 institutions. Low-volume surgeons and hospitals had significantly older and poorer-risk patients with various comorbidities. The operative mortality rate decreased with surgeon volume, 2.5% in S1 and 0.6% in S4. The operative mortality was 3.1% in H1, 1.7% in H2, and 1.2% in H3. After risk adjustment for surgeon, hospital volume and patient characteristics, hospital volume was significantly associated with operative morality (H3: OR = 0.53, 95% CI 0.43-0.63). CONCLUSIONS: We demonstrate hospital volume has an impact on postoperative mortality after TG in a nationwide population study. These findings suggest centralization may improve outcomes after TG.

Secondary prevention with medications is essential for the better prognosis of patients who have experienced cardiovascular events. We aimed to evaluate the use of guideline-based medications for secondary prevention in older adults in the community settings after discharge following percutaneous coronary intervention (PCI). A retrospective cohort study was conducted using anonymized claims data of older beneficiaries in a suburban city of Japan between April 2012 and March 2015. The prescriptions of antiplatelets, statins, angiotensin-converting enzyme inhibitors (ACEi)/angiotensin II receptor blockers (ARB), and β-blockers were evaluated for 3 months before and after the month in which the participants underwent PCI. Multivariable logistic regression analysis was conducted to evaluate the associations of age ("pre-old" group [63-72 years] vs. "old" group [≥ 73 years]) and sex with the prescriptions, adjusting for whether a participant was followed-up by the PCI-performing hospital. Of 815 participants, 59.6% constituted the old group and 70.9% were men. The prescription rates for antiplatelets, statins, ACEi/ARB, and β-blockers after discharge were 94.6%, 65.0%, 59.3%, and 32.9%, respectively. The adjusted analysis indicated that statins were less likely to be prescribed for the old group (adjusted odds ratio [aOR], 0.70; 95% confidence interval [CI], 0.51-0.95; p = 0.023) and for men (aOR, 0.64; 95% CI, 0.45-0.89; p = 0.008). β-blockers were more likely to be prescribed for men (aOR, 1.66; 95% CI, 1.17-2.33; p = 0.004). Our results suggest the potential for improvements in secondary prevention by increasing the prescription rates of guideline-based medications in this population.

BACKGROUND: In 2015, an academic-led surgical quality improvement (QI) programme was initiated in Japan to use database information entered from 2013 to 2014 to identify institutions needing improvement, to which cardiovascular surgery experts were sent for site visits. Here, posthoc analyses were used to estimate the effectiveness of the QI programme in reducing surgical mortality (30-day and in-hospital mortality). METHODS: Patients were selected from the Japan Cardiovascular Surgery Database, which includes almost all cardiovascular surgeries in Japan, if they underwent isolated coronary artery bypass graft (CABG), valve or thoracic aortic surgery from 2013 to 2016. Difference-in-difference methods based on a generalised estimating equation logistic regression model were used for pre-post comparison after adjustment for patient-level expected surgical mortality. RESULTS: In total, 238 778 patients (10 172 deaths) from 590 hospitals, including 3556 patients seen at 10 hospitals with site visits, were included from January 2013 to December 2016. Preprogramme, the crude surgical mortality for site visit and non-site visit institutions was 9.0% and 2.7%, respectively, for CABG surgery, 10.7% and 4.0%, respectively, for valve surgery and 20.7% and 7.5%, respectively, for aortic surgery. Postprogramme, moderate improvement was observed at site visit hospitals (3.6%, 9.6% and 18.8%, respectively). A difference-in-difference estimator showed significant improvement in CABG (0.29 (95% CI 0.15 to 0.54), p<0.001) and valve surgery (0.74 (0.55 to 1.00); p=0.047). Improvement was observed within 1 year for CABG surgery but was delayed for valve and aortic surgery. During the programme, institutions did not refrain from surgery. CONCLUSIONS: Combining traditional site visits with modern database methodologies effectively improved surgical mortality in Japan. These universal methods could be applied via a similar approach to contribute to achieving QI in surgery for many other procedures worldwide.

PURPOSES: The aim of this study was to clarify the impact of a board certification system and the implementation of clinical practice guidelines for pancreatic cancer (PC) on the mortality of pancreaticoduodenectomy in Japan. METHODS: By a web questionnaire survey via the National Clinical Database (NCD) for departments participating in the NCD, quality indicators (QIs) related to the treatment for PC, namely the board certification systems of various societies and the adherence to clinical practice guidelines for PC, were investigated between October 2014 and January 2015. A multivariable logistic regression analysis was performed to evaluate the relationship between the QIs and mortality of pancreaticoduodenectomy. RESULTS: Of 1415 departments that registered at least 1 pancreaticoduodenectomy between 2013 and 2014 in NCD, 631 departments (44.6%), which performed pancreaticoduodenectomy for a total of 11,684 cases, answered the questionnaire. The mortality of pancreaticoduodenectomy was positively affected by the board certification systems of the Japanese Society of Gastroenterological Surgery, Japanese Society of Hepato-Biliary-Pancreatic Surgery, Japanese Society of Gastroenterology, and Japanese Society of Medical Oncology as well as by institutions that used magnetic resonance imaging of ≥ 3 T for the diagnosis of PC in principle. CONCLUSIONS: The measurement of the appropriate QIs is suggested to help improve the mortality in pancreaticoduodenectomy. Masamichi Mizuma and Hiroyuki Yamamoto equally contributed.

Aim: To investigate the effectiveness of the institutional medical structure and of the implemented clinical practice guidelines for improving colon cancer surgical outcomes. Methods: We conducted a web-based questionnaire survey among departments registered at the National Clinical Database in Japan from October 2014 to January 2015 to assess the association between quality indicators (QIs), including structure and process indicators (clinical practice guideline adherence), and the risk-adjusted odds ratio for operative mortality (AOR) after right hemicolectomy for colorectal cancer during the study period. Results: Among the 2064 departments registering at least one colorectal surgery during the study period, we obtained responses from 814 departments (39.4%). Our analysis on data from 22 816 patients with right hemicolectomy demonstrated that three structural QIs (certification of training hospitals by the Japanese Society of Gastroenterological Surgery and the presences of board-certified gastroenterological and colorectal surgeons) were associated with significantly lower AOR (P < .001, P = .02, and P = .05, respectively). The "performed at the doctor's discretion" answer was associated with poorer short-term outcomes in six process QIs than other answers. Conclusion: The board certification system for gastroenterological and colorectal surgeons and the adherence to the clinical guidelines improve the operative mortality after right hemicolectomy. It is desired to clarify the most suitable QIs to reduce the operative mortality after colorectal surgery.

OBJECTIVES: To evaluate the background trends and surgical outcomes for more than 10 000 patients with acute type A dissection in Japan in a recent 8-year period. METHODS: Data on replacement of the ascending aorta and/or aortic arch for acute type A dissection were collected from the Japan Cardiovascular Surgery Database from 2008 to 2015. Linear-by-linear association tests or Cuzick's test for trend was used to evaluate group trends over time. The results were calculated for ascending or hemiarch replacement and arch replacement. A multivariable logistic regression model was used to calculate the risk-adjusted operative mortality rate. RESULTS: A total of 11 843 patients were included. The overall 30-day mortality and operative mortality rates were 7.6% and 9.5%, respectively. The number of surgically treated cases increased from 2436 patients in 2008-2009 to 3533 in 2014-2015, a 45.0% increase. A trend analysis revealed significant changes in patient characteristics with time, including increasing age and rate of preoperative renal failure. Despite worsening risk factors, the unadjusted operative mortality rate with arch replacement showed a significant downward trend (P = 0.01; test of trend). The risk-adjusted mortality rate showed a downward trend both in ascending aorta or hemiarch replacement and arch replacement, although the trend was not statistically significant (P > 0.05). CONCLUSIONS: Unadjusted and adjusted operative deaths have shown a decreasing trend, although patients undergoing surgery for acute type A dissection have demonstrated worsening of risk factors, such as age and renal failure. The number of surgeries performed for acute type A dissection significantly increased throughout the study period in Japan.

BACKGROUND: This study aimed to define an objective evidence-based threshold of high-volume hospitals (HVHs) for pancreatoduodenectomy (PD) using nationwide data systems. METHODS: A total of 36,453 patients underwent PD in 1,499 hospitals from 2012 to 2015 were collected from the National Clinical Database in Japan. Restricted cubic spline model with risk adjustment was used for definition of an objective evidence-based threshold of HVHs. RESULTS: The restricted cubic spline curve of 30-day and in-hospital mortality showed a continuous decrease with an increase in hospital volume and plateau phase of mortality was detected between approximately 30 and 50 PDs/year. On the basis of this curve, we defined hospitals ≥30 PDs/year as HVHs and ≤29 PDs/year as non-HVHs. We also sub-classified hospitals <5, 5-29, 30-49, and ≥50 PDs/year as low-volume, intermediate-volume, high-volume, and very high-volume hospitals using the spline curve. The odds ratio (OR) of risk-adjusted mortality decreased as hospital volume increased, with an OR of 0.34 for HVHs and 0.26 for very HVHs compared with low-volume hospitals. CONCLUSIONS: We consider that this concept is applicable to other high-risk procedures for reducing mortality after these procedures, which could improve medical care and health services.

BACKGROUND: Given the rapid expansion in the use of transcatheter aortic valve implantation (TAVI), recent outcomes of surgical aortic valve replacement (SAVR) should be re-evaluated.Methods and Results:Using the data from the Japan Cardiovascular Surgery Database of 160 enrolled hospitals, trends in elective isolated SAVR were evaluated until the introduction of TAVI in Japan. Trend analyses were performed over 4 periods: period 1, 2008-2009 (4,415 cases); period 2, 2010-2011 (4,861 cases); period 3, 2012-2013 (5,674 cases); and period 4, 2014-2015 (5,563 cases). Baseline risk, evaluated on JapanSCORE, increased significantly over the 4 periods, from a median of 1.56 (IQR, 0.99-2.61) in period 1 to 2.08 (IQR, 1.33-3.96) in period 4 (P<0.001, trend test). Despite the increased risk, the composite major complication and operative mortality rate decreased significantly (10.7% in period 1 to 9.2% in period 4, P=0.01). Using a risk-adjusted model, the OR of operative mortality was 1.61 (95% CI: 1.29-2.02) in period 1 (P<0.0001) compared with period 4. An increase in the use of bioprostheses was also observed, from 60.4% to 76.8% (P<0.001) over the 4 periods. CONCLUSIONS: Even in a short 8-year period, SAVR outcomes improved in Japan. This should be taken into account when discussing the indications for aortic valve intervention.

BACKGROUND: In 2009, the Japan Esophageal Society (JES) established a system for certification of qualified surgeons as "Board Certified Esophageal Surgeons" (BCESs) or institutes as "Authorized Institutes for Board Certified Esophageal Surgeons" (AIBCESs). We examined the short-term outcomes after esophagectomy, taking into consideration the certifications statuses of the institutes and surgeons. METHODS: This study investigated patients who underwent esophagectomy for thoracic esophageal cancer and who were registered in the Japanese National Clinical Database (NCD) between 2015 and 2017. Using hierarchical multivariable logistic regression analysis adjusted for patient-level risk factors, we determined whether the institute's or surgeon's certification status had greater influence on surgery-related mortality or postoperative complications. RESULTS: Enrolled were 16,752 patients operated on at 854 institutes by 1879 surgeons. There were significant differences in the backgrounds and incidences of postoperative complications and surgery-related mortality rates between the 11,162 patients treated at AIBCESs and the 5590 treated at Non-AIBCESs (surgery-related mortality rates: 1.6% vs 2.8%). There were also differences between the 6854 patients operated on by a BCES and the 9898 treated by a Non-BCES (1.7% vs 2.2%). Hierarchical logistic regression analysis revealed that surgery-related mortality was significantly lower among patients treated at AIBCESs. The institute's certification had greater influence on short-term surgical outcomes than the operating surgeon's certification. CONCLUSIONS: The certification system for surgeons and institutes established by the JES appears to be appropriate, as indicated by the improved surgery-related mortality rate. It also appears that the JES certification system contributes to a more appropriate medical delivery system for thoracic esophageal cancer in Japan.

BACKGROUND: Ventricular septal defect (VSD) after myocardial infarction (MI) is a rare but fatal complication. We report patients' characteristics and operative outcomes after surgical repair of post-MI VSD using a national database of Japan.Methods and Results:This was a retrospective review of the Japan Adult Cardiovascular Surgery Database (JCVSD) to identify adults (age ≥18 years) who underwent surgical repair of post-MI VSD between 2008 and 2014. The primary outcome was operative death. We identified 1,397 patients (671 male [48%], 74.1±9.3 years old) undergoing surgical repair of post-MI VSD among 288,736 patients undergoing cardiac surgery enrolled in the JCVSD during the same period. Of these, 1,075 (77.0%) were supported preoperatively with an intra-aortic balloon pump. Surgical status was urgent in 391 (28.0%) and emergency/salvage in 731 (52.3%). Concomitant coronary artery bypass grafting was performed in 475 (34.0%). Overall 30-day and operative mortalities were 24.3% and 33.0%, respectively. Operative mortality varied according to surgical status: 15.6% in elective, 30.9% in urgent, and 40.6% in emergency/salvage cases. Multivariable analysis identified advanced age and emergency/salvage status as being strongly associated with increased odds of operative death. CONCLUSIONS: Post-MI VSD remains a devastating complication in Japan as well as in the USA and Europe.

BACKGROUND: It remains unknown how much institutional medical structure and process of implementation of clinical practice guidelines for esophageal cancers can improve quality of surgical outcome in Japan. METHODS: A web-based questionnaire survey was performed for departments registered in the National Clinical Database in Japan from October 2014 to January 2015. Quality indicators (QIs) including structure and process indicators (clinical practice guideline adherence) were evaluated on the risk-adjusted odds ratio for operative mortality (AOR) of the patients using registered cases in the database who underwent esophagectomy and reconstruction in 2013 and 2014. RESULTS: Among 916 departments which registered at least one esophagectomy case during the study period, 454 departments (49.6%) responded to the questionnaire. Analyses of 6661 cases revealed that two structure QIs (certification of training hospitals by Japan Esophageal Society and presence of board-certified esophageal surgeons) were associated with significantly lower AOR (p < 0.001 and p = 0.005, respectively). One highly recommended process QI regarding preoperative chemotherapy had strong tendency to associate with lower AOR (p = 0.053). In two process QIs, the answer "performed at the doctor's discretion" showed a significant negative impact on prognosis, suggesting importance of institutional uniformity. CONCLUSIONS: The medical institutional structure of board-certified training sites for esophageal surgeons and of participation of board-certified esophageal surgeons improves surgical outcome in Japan. Establishment of appropriate QIs and their uniform implementation would be crucial for future quality improvement of medical care in esophagectomy.

BACKGROUND: Despite interest in surgeon and hospital volume effects on distal gastrectomy, clinical significance has not been confirmed in a large-scale population. We studied to clarify the effects of surgeon and hospital volume on postoperative mortality after distal gastrectomy for gastric cancer among Japanese patients in a nationwide web-based data entry system. METHODS: We extracted data on distal gastrectomy for gastric cancer from the National Clinical Database between 2011 and 2015. The primary outcome was operative mortality. Hospital volume was divided into 3 tertiles: low (1-22 cases per year), medium (23-51) and high (52-404). Surgeon volume was divided into the 5 groups: 0-3, 4-10, 11-20, 21-50, 51 + cases per year. We calculated the 95% confidence interval (CI) for the mortality rate based on odds ratios (ORs) estimated from a hierarchical logistic regression model. RESULTS: We analyzed 145,523 patients at 2182 institutions. Operative mortality was 1.9% in low-, 1.0% in medium- and 0.5% in high-volume hospitals. The operative mortality rate decreased definitively with surgeon volume, 1.6% in the 0-3 group and 0.3% in the 51 + group. After risk adjustment for surgeon and hospital volume and patient characteristics, hospital volume was significantly associated with operative morality (medium: OR 0.64, 95% CI 0.56-0.73, P < 0.001; high: OR 0.42, 95% CI 0.35-0.51, P < 0.001). CONCLUSIONS: We demonstrate that hospital volume can have a crucial impact on postoperative mortality after distal gastrectomy compared with surgeon volume in a nationwide population study. These findings suggest that centralization may improve outcomes after distal gastrectomy.

OBJECTIVES: High prevalence of iron deficiency (ID) and cardiomyopathy have been observed in patients with end-stage kidney disease (ESKD). Our objective was to clarify associations between ID and cardiac remodeling in patients with ESKD. DESIGN AND METHODS: A cross-sectional study was conducted using 1974 Japanese patients with ESKD at the initiation of maintenance dialysis. Levels of hemoglobin (Hb), iron status, and cardiac enlargement as assessed by the cardiothoracic ratio (CTR) were determined immediately before the first hemodialysis session. Circulatory ID was defined as transferrin saturation (TSAT) < 20%, and stored ID was defined as ferritin level <100 ng/dL. RESULTS: The mean age was 67 years. Median CTR was 54.0%. The prevalence of circulatory and stored ID was found to be 38% and 34%, respectively. CTR was higher in patients with circulatory ID than in those without. Even in ESKD patients without overhydration, significant negative association was observed between TSAT and CTR. Higher odds ratios in parallel with higher CTR categories compared with the reference category of CTR <45% were found in patients with TSAT <20% on multinomial analysis, but ferritin did not show any significant associations. The odds ratio for CTR >54% showed an upward trend in patients with TSAT <20% (odds ratio: 1.3) and <10% (odds ratio: 1.6) compared with the reference, even after adjusting for confounding variables such as Hb and ferritin. However, that phenomenon was eliminated by adding usage of an iron agent. CONCLUSIONS: Circulatory ID is closely associated with an enlarged heart independent of ferritin and Hb. Iron supplementation in the predialysis phase of chronic kidney disease may prevent cardiac remodeling independent of Hb level in patients chronic kidney disease.

Background and Aim: Benchmarking has proven beneficial in improving the quality of surgery. Mortality rate is an objective indicator, of which the 30-day mortality rate is the most widely used. However, as a result of recent advances in medical care, the 30-day mortality rate may not cover overall surgery-related mortalities. We examined the significance and validity of the 30-day mortality rate as a quality indicator. Methods: The present study was conducted on cancer surgeries of esophagectomy, total gastrectomy, distal gastrectomy, right hemicolectomy, low anterior resection, hepatectomy, and pancreaticoduodenectomy that were registered in the first halves of 2012, 2013 and 2014 in a Japanese nationwide large-scale database. This study examined the mortality curve for each surgical procedure, "sensitivity of surgery-related death" (capture ratio) at each time point between days 30-180, and the association between mortality within 30 days, mortality after 31 days, and preoperative, perioperative, and postoperative factors. Results: Surgery-related mortality rates of each surgical procedure were 0.6%-3.0%. Regarding 30-day mortality rates, only 38.7% (esophagectomy) to 53.3% (right hemicolectomy) of surgery-related mortalities were captured. The capture ratio of surgery-related deaths reached 90% or higher for 120-day to 150-day mortality rates. Factors associated with mortality rate within 30 days/after the 31st day were different, depending on the type of surgical procedure. Conclusion: Thirty-day mortality rate is useful as a quality indicator, but is not necessarily sufficient for all surgical procedures. Quality of surgery may require evaluation by combining 30-day mortality rates with other indicators, depending on the surgical procedure.

OBJECTIVE: To assess the use of laparoscopic surgeries (LS) and the association between its performance and hospitals' preference for LS over open surgeries. SUMMARY BACKGROUND DATA: LS is increasingly used in many abdominal surgeries, albeit both with and without solid guideline recommendations. To date, the hospitals' preference (LS vs. open surgeries) and its association with in-hospital outcomes has not been evaluated. METHODS: We enrolled patients undergoing 8 types of gastrointestinal surgeries in 2011-2013 in the Japanese National Clinical Database. We assessed the use of LS and the occurrences of surgery-related morbidity and mortality during the study period. Further, for 4 typical LS procedures, we assessed the hospitals' preference for LS by modeling the propensity to perform LS (over open surgeries) from patient-level factors, and estimating each institution's observed/expected (O/E) ratio for LS use. Institutions with O/E>2 were defined as LS-dominant. Using hierarchical logistic regression models, we assessed the association between LS preference and in-hospital outcomes. RESULTS: Among 1,377,118 patients undergoing gastrointestinal procedures in 2,336 participating hospitals, use of LS increased in all 8 procedures (35.1% to 44.7% for distal gastrectomy (DG), and 27.5% to 43.2% for right hemi colectomy (RHC)). Those operated at LS-dominant hospitals were at an increased risk of operative death (OR 1.83 [95%CI, 1.37-2.45] for DG, 1.79 [95%CI, 1.43-2.25] for RHC) compared to standard O/E level hospitals (0.5≤O/E<2.0). CONCLUSIONS: LS use widely increased during 2011-2013 in Japan. Facilities with higher than expected LS use had higher mortality compared to other hospitals, suggesting a need for careful patient selection and dissemination of the procedure.

Objectives: Infective endocarditis (IE) has an extremely poor prognosis unless appropriate treatment is received. Hemodialysis patients with IE show higher rates of morbidity and mortality in comparison with non-dialysis patients with IE. We focused on hemodialysis patients, as well as patients in other stages of chronic kidney disease. We sought to assess the relationship between renal function and mortality in patients with IE.<br>Methods: We carried out a retrospective cohort study on 45 consecutive patients with IE in an urban teaching hospital between November 2003 and August 2008. We collected demographic and clinical data as well as pre- and post-discharge outcomes. Patients were subdivided into four groups according to their eGFR level at admission: A: eGFR≧60 ml/min/1.73 m² (n=23); B: eGFR 30-59 ml/min/1.73 m² (n=15); C: eGFR<30 ml/min/1.73 m² (n=3); and, D: dialysis patients (n=3). It was not possible to determine the outcome status of one patient. The Trend Test was used to evaluate the association between renal function and mortality.<br>Results: There were 29 male and 16 female patients with IE and the mean age was 67.9+-17.6 (SD). There were 10 diabetic patients (22%). Thirty-nine patients (84%) were either discharged or transferred to another hospital. Seven patients (16%) died: two (9%) Group A patients; three (20%) Group B patients; no Group C patients; and, two (67%) Group D patients. Patients with lower eGFR had higher mortality rates (Trend Test, P=0.046).<br>Conclusion: We presume a trend towards a higher mortality rate in conjunction with advancing CKD stage.