Objective: In Japan, supplementation with 400 µg of folic acid per day is recommended for women who are planning to get pregnant to decrease the risk of their babies getting neural tube defects (NTD). However, the proportion of women who have taken folic acid supplements before conception is low among Japanese pregnant women. In addition, the dietary intake of folic acid has not yet reached the government recommended dietary intake levels (480 µg per day). This study aimed to clarify the prevalence and determinants of adequate folic acid supplements among Japanese pregnant women with dietary folic acid intake lower than 480 µg per day.Methods: This cross-sectional study was a part of the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study. We collected information on folic acid supplements before conception, sociological/lifestyle characteristics, and food consumption. The primary outcome was the use of folic acid supplements (adequate or inadequate, based on the timing of initiation of folic acid supplements). Multiple logistic regression analysis was used to examine the association between sociological/lifestyle characteristics and the adequate intake of folic acid supplements.Results: Among the 11,562 pregnant women who took lower than 480 µg per day of folic acid from food, the prevalence of adequate users was 18.0%. Pregnant women who reported adequate use of folic acid supplements were more likely to be older and educated; and reported higher household income, and history of fertility treatment. Conversely, they were less likely to be ever or current smokers and multipara.Conclusion: This study found that the prevalence of folic acid supplements use for the prevention of NTD among Japanese pregnant women was still low.

Influenza vaccination is the most effective method for preventing influenza virus infection. The incidence of influenza is higher in schoolchildren than other age groups. This study evaluated the effectiveness of seasonal inactivated influenza vaccination (IIV) in a community population of schoolchildren during two seasons. This study was a cross-sectional survey of public schoolchildren based on data collected in the 2012/2013 and 2014/2015 seasons. The questionnaire was distributed to all public schoolchildren of target grade in a survey area, and 7945 respondents were included in the analysis. The vaccination status and influenza onset were defined based on the self-reported questionnaire by parents or guardians. Generalized linear mixed models were used to adjust clustering within schools and individual covariates and calculate odds ratios (ORs) and 95% confidence intervals (CIs) for associations between vaccination status and influenza onset. The influenza incidence was higher in the 2015 than the 2013 survey (25% versus 17%), although the vaccination rates were comparable between the two seasons. Receiving one- or two-dose vaccination was more protective against influenza than non-vaccination in both the 2013 (OR, 0.77; 95%CI, 0.65-0.92) and 2015 (OR, 0.88; 95%CI, 0.75-1.02) surveys. Full vaccination was also more protective in both the 2013 (OR, 0.75; 95%CI, 0.62-0.89) and 2015 (OR, 0.86; 95%CI, 0.74-1.00) surveys. Seasonal IIV was protective against influenza for Japanese schoolchildren in a community-based real-world setting. The difference in clinical effectiveness of IIV between the two seasons was likely due to the antigenic mismatch between the circulating and vaccine strains.

Backgrounds: The effect of breastfeeding on weight status of individuals after a large-scale natural disaster in a developed country is unclear. We aimed to investigate the association of breastfeeding with childhood overweight and/or obesity in areas affected by the Great East Japan Earthquake. Materials and Methods: From health examination records of 15,563 children, we retrospectively obtained anthropometric and feeding practice (formula, mixed, and breastfeeding) data during early childhood. According to their age at the time of the earthquake, we subdivided the children into study groups 1 (42-48 months), 2 (18-24 months), and 3 (<3 months). Overweight, obesity, and underweight were defined on the basis of body mass index. To assess the association between feeding practice at 3 months of age and the risk of overweight and/or obesity at 3 years of age, we developed generalized linear mixed models that included a random effect of the municipality of residence; for this analysis, we combined "mixed feeding" and "formula feeding" into a single category: "mixed plus formula feeding." Results: Mixed- plus formula-fed children had a significantly higher risk of overweight and/or obesity than breastfed children in all three study groups (odds ratios, 1.20-2.22; all p ≤ 0.047). The rate of underweight at 3 years of age was ≤0.3%, irrespective of feeding practices. Conclusion: Breastfeeding, even during a large-scale natural disaster in a developed country, maintained its protective effect against overweight and/or obesity in childhood.

<sec><title>Objectives</title>Healthy-weight children tend to gain weight during winter but lose weight during summer. However, overweight elementary school children have shown accelerated summertime weight gain. Whether this seasonal growth variation occurs during preschool period is of substantial interest. </sec><sec><title>Methods</title>Data were derived from a nationwide retrospective cohort of nursery school children. Eight consecutive sets of longitudinal measurements on height and weight were obtained from 15 259 preschool children. Thereafter, growth in height, weight and body mass index (BMI) over a period of 6 months was calculated. Summertime growth was defined as that from April to October, whereas wintertime growth was defined as that from October to April of the following year. Longitudinal growth seasonality was analysed by classifying children according to their BMI status at the age of elementary school entry. </sec><sec><title>Results</title>Accelerated summertime weight and BMI gain were observed among children with obesity. This distinctive growth seasonality was detected from around age 2. Children having this growth seasonality at approximately 2 years of age tended to be obese at the age of elementary school entry (OR: 3.7; 95% CI: 2.9 to 4.6; p&lt;0.0001). In height gain, obese children were growing apparently faster than those in the other groups at all ages. </sec><sec><title>Conclusion</title>Early excessive growth with distinct seasonality was observed in preschool obese children. These findings suggest that individuals involved in child healthcare should pay closer attention to early excessive growth with distinct seasonality in preschool obesity. </sec>

We investigated whether machine learning methods could potentially identify a subgroup of persons with autism spectrum disorder (ASD) who show vitamin B6 responsiveness by selected phenotype variables. We analyzed the existing data from our intervention study with 17 persons. First, we focused on signs and biomarkers that have been identified as candidates for vitamin B6 responsiveness indicators. Second, we conducted hypothesis testing among these selected variables and their combinations. Finally, we further investigated the results by conducting cluster analyses with two different algorithms, affinity propagation and k-medoids. Statistically significant variables for vitamin B6 responsiveness, including combination of hypersensitivity to sound and clumsiness, and plasma glutamine level, were included. As an a priori variable, the Pervasive Developmental Disorders Autism Society Japan Rating Scale (PARS) scores was also included. The affinity propagation analysis showed good classification of three potential vitamin B6-responsive persons with ASD. The k-medoids analysis also showed good classification. To our knowledge, this is the first study to attempt to identify subgroup of persons with ASD who show specific treatment responsiveness using selected phenotype variables. We applied machine learning methods to further investigate these variables' ability to identify this subgroup of ASD, even when only a small sample size was available.

Introduction We experienced a devastating disaster, the Great East Japan Earthquake, in 2011. Some previous studies showed that disasters affected maternal blood pressure and their health. Its longer effect on pregnant women is necessary to investigate. Objective The purpose of this present study was to investigate if maternal disaster exposure affected their blood pressure. Methods The relationship between disaster exposure and maternal outcomes was retrospectively analyzed using the data of 4426 women who were recruited to the Tohoku Medical Megabank Birth and Three-generation Cohort Study, which was conducted in the years 2013–2017. Women were classified into three groups by the severity of the destruction of their house: group A, no destruction/did not live in the disaster-hit area; group B, half/a part of the house was destroyed; and group C, house totally/mostly destroyed. Multiple logistic regression analysis was performed to investigate the relationship between disaster exposure and hypertensive disorders of pregnancy, adjusting for body mass index, age, smoking, drinking, income, parity, and multiple pregnancy. Results Of 4,426 women eligible for the analyses, the houses of 489 women (11.0%) were totally or mostly destroyed, and the houses of 1706 women (38.5%) were half or partly destroyed. Those whose houses were not destroyed or did not live in the area affected by the disaster included 2,231 women (50.4%). The prevalence of hypertensive disorders of pregnancy in groups B and C were 0.82 and 1.47 times higher than in group A, but there was no statistical significance. Discussion Involvement in a disaster event about three to six years before pregnancy was not related to a higher prevalence of hypertensive disorders of pregnancy.

BACKGROUND: The body mass index (BMI) of preschool children from 4 years of age through primary school has increased since the Great East Japan Earthquake, but that of children aged under 3 years has not been studied. This study evaluated how the anthropometrics of younger children changed following the earthquake. METHODS: Height and weight data of children living in northeast Japan were collected from 3-, 6-, 18-, and 42-month child health examinations. We compared the changes in BMI, weight, and height among infants affected by the earthquake between their 3- and 6-month health examinations, toddlers affected at 21-30 months of age (affected groups), and children who experienced the earthquake after their 42-month child health examination (unaffected group). A multilevel model was used to calculate the BMI at corresponding ages and to adjust for the actual age at the 3-month health examination, health examination interval, and gestational age. RESULTS: We recruited 8,479 boys and 8,218 girls living in Fukushima, Miyagi, and Iwate Prefectures. In the infants affected between their 3- and 6-month health examinations in Fukushima, the change in BMI at 42 months of age was greater than among the unaffected children. In the toddlers affected at 21-30 months of age in Fukushima, the change in BMI was greater, but changes in weight and height were less. CONCLUSIONS: Affected infants and toddlers in Fukushima suggested some growth disturbances and early adiposity rebound, which can cause obesity. The future growth of children affected by disasters should be followed carefully.

Objective: There have been no reports evaluating the physical growth in early childhood in Fukushima Prefecture after the Great East Japan Earthquake. We retrospectively investigated the health examination data in early childhood (aged 0-3 years). Methods: We divided the affected children into respective groups according to the interval from the disaster to the time of health examination and age as follows: group I, birth to 3-4 months in boys (1.81 (range, 0-6 months)) and girls (1.79 (range, 0-7 months)); group II, 3-4 months to 6-10 months in boys (6.37 (range, 3-9 months)) and girls (6.35 (range, 3-9 months)); group III, 6-10 months and 18 months in boys (16.2 (range, 5-22 months)) and girls (16.9 (range, 5-22 months)); and group IV, 18 months to 36-42 months in boys (21.0 (range, 18-24 months)) and girls (21.0 (range, 18-24 months)). Using height and body mass index, the health status of each group was compared with that of unaffected controls (ie, children who experienced the disaster after their health examination at 36-42 months). Results: The change in body mass index between the health examinations at 18 months and 36-42 months was significantly increased in group I (95% CI: all boys, 0.192 to 0.276 vs -0.006 to 0.062, P<0.001 and all girls, 0.108 to 0.184 vs -0.109 to -0.035, P<0.001) and group II (95% CI: all boys, 0.071 to 0.141 vs -0.006 to 0.062, P=0.002 and all girls, -0.042 to 0.024 vs -0.109 to -0.035, P=0.013). Conclusions: Children who were affected by the disaster in Fukushima Prefecture in early childhood were overweight. The use of pre-existing information, such as health examination data, was beneficial for investigating the physical growth of affected children.

OBJECTIVES: Longitudinal growth data of children were analyzed to clarify the relationship between the timing of body mass index (BMI) rebound and obesity risk in later ages. SUBJECTS/METHODS: Of 54 558 children born between April 2004 and March 2005 and longitudinally measured in April and October every year in the preschool period, 15 255 children were analyzed wherein no longitudinal measurement is missing after 1 year of age. BMI rebound age was determined as the age with smallest BMI value across longitudinal individual data after 1 year of age. Rebound age was compared between overweight and non-overweight groups. The subjects were divided into groups based on the timing of rebound. The sex- and age-adjusted mean of the BMI, height and weight s.d. scores for age group, along with 6 months weight and height gain, were compared among groups using analysis of covariance. RESULTS: Among those who were overweight at 66-71 months of age, BMI rebound age obtained at approximately 3 years of age was compared with the non-overweight group, whose BMI rebound age was utmost 66 months or later (P<0.001). The comparison among BMI age group showed that earlier BMI rebound results in larger BMI (P<0.001) and larger weight and height gain after the rebound (P<0.001). Among the group with BMI rebound earlier than 30 months of age, low BMI was observed (P<0.001). Slight elevation of height and weight gain was observed before the BMI rebound among groups with rebound age earlier than 60 months of age (P<0.001). CONCLUSION: Earlier BMI rebound timing with pre-rebound low BMI leads to greater childhood obesity risk; hence, early detection and prevention is necessary for such cases.

BACKGROUND: Data for earthquake-related alterations in physique among young children in developed countries is lacking. The Great East Japan Earthquake caused severe damage in Iwate, Miyagi, and Fukushima Prefectures in northeastern Japan. METHODS: We retrospectively obtained anthropometric measurements in nursery school from 40,046 (cohort 1, historical control) and 53,492 (cohort 2) children aged 3.5-4.5 years without overweight in October 2008, and in October 2010, respectively. At the time of the earthquake in March, 2011, children in cohort 1 had already graduated from nursery school; however, children in cohort 2 were still enrolled in nursery school at this time. We compared the onset of overweight at 1 year after the baseline between children enrolled in their school located in one of the three target prefectures versus those in other prefectures using a logistic regression model, with adjustment for sex, age, history of disease, and obesity index at baseline. Overweight was defined as an obesity index of >+15%, which was calculated as (weight minus sex- and height-specific standard weight)/sex- and height-specific standard weight. RESULTS: The odds ratio (OR) for the onset of overweight in the three target prefectures was significant in cohort 2 (OR 1.25; 95% confidence interval [CI], 1.01-1.55) but not in cohort 1. When the two cohort were pooled (n = 93,538), the OR of the interaction term for school location × cohort was significant (OR 1.56; 95% CI, 1.09-2.23). CONCLUSIONS: Incident overweight in young children was significantly more common in the three prefectures affected by the Great East Japan Earthquake than in other prefectures after the disaster.

BACKGROUND: The Great East Japan Earthquake followed by tsunamis and the Fukushima Daiichi Nuclear Power Plant (NPP) accident caused catastrophic damage. The effects of the disaster on the growth of affected children are of great concern but remain unknown. METHODS: The subject group was derived from two Japanese nationwide retrospective cohorts (historical control and exposure groups, respectively). The exposure group experienced the disaster at 47-59 months of age. We analyzed longitudinal changes in standard deviation score (SDS) for height and body mass index (BMI) using normal Japanese children's standards. Moreover, we analyzed the details of the affected children in Fukushima using Fukushima-specific growth charts established with the historical control data to clarify any indirect effect of the disaster on growth. RESULTS: Affected children in Fukushima had significantly higher BMI SDS than the historical control group (difference, 0.13; 95% CI: 0.044-0.21, P = 0.0029) and the regional controls (difference, 0.14; 95% CI: 0.074-0.20, P < 0.0001) 1.5 years after the disaster. Similar sustained increases in BMI SDS were also found with Fukushima-specific growth charts, but the phenomenon was detected only in boys. Notably, the BMI SDS of affected children who lived near the NPP had been increasing after the disaster, whereas those in distant areas had not changed. In contrast, height SDS had not changed throughout the analysis. CONCLUSIONS: Prolonged elevated BMI SDS was detected only in affected children in Fukushima. This phenomenon may be explained by an indirect effect of the NPP accident.

BACKGROUND: The evacuation and disruption in housing caused by the 2011 Great East Japan Earthquake and following nuclear radiation may have influenced child health in many respects. However, studies regarding longitudinal childhood growth are limited. Therefore, in this study we aimed to explore the influence of the earthquake on longitudinal changes in body mass index in preschool children. METHODS: Participants were children from nursery schools who cooperated with the study in the Iwate, Miyagi and Fukushima prefectures. The exposed group consisted of children who experienced the earthquake during their preschool-age period (4-5 years old). The historical control group included children who were born 2 years earlier than the exposed children in the same prefectures. Trajectories regarding body mass index and prevalence of overweight/obesity were compared between the two groups using multilevel analysis. Differences in the changes in BMI between before and after the earthquake, and proportion of overweight/obesity was compared between the two groups. We also conducted subgroup analysis by defining children with specific personal disaster experiences within the exposed group. RESULTS: A total of 9722 children were included in the study. Children in the exposed group had higher body mass indices and a higher proportion of overweight after the earthquake than the control group. These differences were more obvious when confined to exposed children with specific personal disaster experiences. CONCLUSIONS: Children's growth and development-related health issues such as increased BMI after natural disasters should evoke great attention.

OBJECTIVE: To investigate the relationship between personal experience of the Great East Japan Earthquake and various disease types among nursery school children. DESIGN: We conducted a nationwide survey of nursery school children born between 2 April 2006 and 1 April 2007. Nursery school teachers completed questionnaires if they agreed to join the study. Questionnaire items for children consisted of their birth year and month, sex, any history of moving into or out of the current nursery school, presence of diseases diagnosed by a physician at the age of 66-78 months and type of disaster experience. The survey was conducted from September 2012 to December 2012. SETTING: Japan, nationwide. PARTICIPANTS: A total of 60 270 nursery school children were included in the analysis, 840 of whom experienced the disaster on 11 March 2011. MAIN OUTCOME MEASURES: The health status of children 1.5 years after the disaster based on nursery school records. RESULTS: Experiencing the disaster significantly affected the prevalence of overall and individual diseases. Furthermore, there was a difference in disease prevalence between boys and girls. In boys, experiencing the tsunami (OR 2.53, 95% CI 1.22 to 5.24) and living in an evacuation centre (OR 2.92, 95% CI 1.46 to 5.83) were remarkably associated with a higher prevalence of atopic dermatitis, but these trends were not observed among girls. Instead, the home being destroyed (OR 3.50, 95% CI 2.02 to 6.07) and moving house (OR 4.19, 95% CI 2.01 to 8.71) were positively associated with a higher prevalence of asthma among girls. CONCLUSIONS: Our study indicates that experiencing the disaster may have affected the health status of nursery school children at least up to 1.5 years after the disaster. Continuous monitoring of the health status of children is necessary to develop strategic plans for child health.

BACKGROUND: To investigate the impact of the Great East Japan Earthquake on preschool children's physical growth in the disaster-affected areas, the three medical universities in Iwate, Miyagi, and Fukushima Prefectures conducted a health examination survey on early childhood physical growth. METHODS: The survey was conducted over a 3-year period to acquire data on children who were born in different years. Our targets were as follows: 1) children who were born between March 1, 2007 and August 31, 2007 and experienced the disaster at 43-48 months of age, 2) children who were born between March 1, 2009 and August 31, 2009 and experienced the disaster at 19-24 months of age, and 3) children who were born between June 1, 2010 and April 30, 2011 and were under 10 months of age or not born yet when the disaster occurred. We collected their health examination data from local governments in Iwate, Miyagi, and Fukushima Prefectures. We also collected data from Aomori, Akita, and Yamagata Prefectures to use as a control group. The survey items included birth information, anthropometric measurements, and methods of nutrition during infancy. RESULTS: Eighty municipalities from Iwate, Miyagi, and Fukushima Prefectures and 21 from the control prefectures participated in the survey. As a result, we established three retrospective cohorts consisting of 13,886, 15,474, and 32,202 preschool children. CONCLUSIONS: The large datasets acquired for the present survey will provide valuable epidemiological evidence that should shed light on preschool children's physical growth in relation to the disaster.

Background: Previous studies have reported controversial results for the association between green tea consumption and low-density lipoprotein (LDL)-cholesterol and body weight. Objective: The objective of this trial was to determine the effects of two kinds of green tea on LDL-cholesterol and body weight. Methods: We randomly assigned 151 participants (98 men, 53 women) aged 30-70 years into three groups: Yabukita green tea group, Benifuuki green tea group, or placebo group. Participants consumed 1.8 g/day of green tea extract powder or placebo for 12 weeks. The primary outcomes were LDL-cholesterol level and body weight, and the secondary outcomes were risk factors for cardiovascular disease. Results: Both Yabukita and Benifuuki green tea significantly lowered LDL-cholesterol. The magnitudes of the lipid-lowering effect of both types of tea were significantly larger than that of placebo. No differences with respect to changes in LDL-cholesterol were observed between the Yabukita and Benifuuki green tea groups. Neither Yabukita nor Benifuuki green tea had any effect on body weight and no difference was observed among groups regarding changes in body weight. Conclusion: Both Yabukita and Benifuuki green tea lowered LDL-cholesterol, and the lipid-lowering effects of these two green teas were not different. Neither tea lowered body weight.

OBJECTIVE: To evaluate the impact of the 2011 great east Japan earthquake on body mass index (BMI) of preschool children. DESIGN: Retrospective cohort study and ecological study. SETTING: Affected prefectures (Fukushima, Miyagi and Iwate) and unaffected prefectures in northeast Japan. PARTICIPANTS: The cohort study assessed 2033 and 1707 boys and 1909 and 1658 girls in 3 affected prefectures and unaffected prefectures, respectively, all aged 3-4 years at the time of the earthquake. The ecological study examined random samples of schoolchildren from the affected prefectures. PRIMARY AND SECONDARY OUTCOME MEASURES: The cohort study compared postdisaster changes in BMIs and the prevalence of overweight and obese children. The ecological study evaluated postdisaster changes in the prevalence of overweight children. RESULTS: 1 month after the earthquake, significantly increased BMIs were observed among girls (+0.087 kg/m(2) vs unaffected prefectures) in Fukushima and among boys and girls (+0.165 and +0.124 kg/m(2), respectively vs unaffected prefectures) in Iwate. 19 months after the earthquake, significantly increased BMIs were detected among boys and girls (+0.137 and +0.200 kg/m(2), respectively vs unaffected prefectures) in Fukushima, whereas significantly decreased BMIs were observed among boys and girls (-0.218 and -0.082 kg/m(2), respectively vs unaffected prefectures) in Miyagi. 1 month after the earthquake, Fukushima, Miyagi and Iwate had a slightly increased prevalence of overweight boys, whereas Fukushima had a slightly decreased prevalence of overweight girls, compared with the unaffected prefectures. The ecological study detected increases in the prevalence of overweight boys and girls in Fukushima who were 6-11 and 6-10 years of age, respectively. CONCLUSIONS: These results suggest that in the affected prefectures, preschool children gained weight immediately after the earthquake. The long-term impact of the earthquake on early childhood growth was more variable among the affected prefectures, possibly as a result of different speeds of recovery.

BACKGROUND: The Great East Japan Earthquake inflicted severe damage on the Pacific coastal areas of northeast Japan. Although possible health impacts on aged or handicapped populations have been highlighted, little is known about how the serious disaster affected preschool children's health. We conducted a nationwide nursery school survey to investigate preschool children's physical development and health status throughout the disaster. METHODS: The survey was conducted from September to December 2012. We mailed three kinds of questionnaires to nursery schools in all 47 prefectures in Japan. Questionnaire "A" addressed nursery school information, and questionnaires "B1" and "B2" addressed individuals' data. Our targets were children who were born from April 2, 2004, to April 1, 2005 (those who did not experience the disaster during their preschool days) and children who were born from April 2, 2006, to April 1, 2007 (those who experienced the disaster during their preschool days). The questionnaire inquired about disaster experiences, anthropometric measurements, and presence of diseases. RESULTS: In total, 3624 nursery schools from all 47 prefectures participated in the survey. We established two nationwide retrospective cohorts of preschool children; 53,747 children who were born from April 2, 2004, to April 1, 2005, and 69,004 children who were born from April 2, 2006, to April 1, 2007. Among the latter cohort, 1003 were reported to have specific personal experiences with the disaster. CONCLUSIONS: With the large dataset, we expect to yield comprehensive study results about preschool children's physical development and health status throughout the disaster.

OBJECTIVE: To examine lifestyle habits and cancer screening behavior in relation to a family history of cancer among Japanese women. METHODS: A cross-sectional study was conducted based on baseline data from the Japan Nurses' Health Study collected from June 2001 to March 2007. Participants were 47,347 female nurses aged 30-59 years residing in 47 prefectures in Japan. We compared lifestyle habits and the utilization of cancer screenings (cervical and breast) between women with and without a family history of the relevant cancer. RESULTS: Although there were no differences in lifestyle habits with the exception of smoking status, women with a family history of uterine cancer were more likely to have undergone cervical cancer screenings (p<0.01). Women with a family history of breast cancer were also more likely to have undergone breast cancer screenings regardless of their age (p<0.01), but lifestyle behaviors did not differ. Among women with a family history of uterine cancer, those with a sister history were more likely to have undergone not only cervical (OR, 1.89; 95% CIs, 1.39-2.58), but also breast cancer screenings (OR, 1.54; 95% CIs 1.13-2.09). CONCLUSION: Having a family history of cancer was associated with cancer screening behavior, but not health promotive behaviors.