AIMS: For older adults with limited life space and activity, social participation in the neighborhood community is essential to ensure social interaction and activity levels. This study examined the association between social participation in the neighborhood community and the onset of disability in older adults with different life spaces and activities. METHODS: The participants were 9513 older adults from a cohort study conducted at the National Center for Geriatrics and Gerontology Study of Geriatric Syndromes (NCGG-SGS). Social participation in the neighborhood community was assessed by participating in the community meetings. Life space with activities was evaluated using the Activity Mobility Index (AMI) developed in the NCGG-SGS, with higher scores indicating better mobility and movement. The participants were divided into four groups based on the quartiles of their AMI scores (Q1-Q4). Cox proportional hazard models were used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) for disability incidence by social participation in each quartile. RESULTS: Over the 2-year follow-up period, disability occurred in 4.3% of the participants (n = 409). In the Q1 group, participants who participated in the neighborhood community had a significantly lower risk of developing a disability than those who did not (HR, 0.47; 95% CI, 0.28-0.76). There were no significant differences in onset of disability between the presence and absence of social participation for groups Q2, Q3, and Q4. CONCLUSIONS: Social participation in the neighborhood community was associated with the onset of disability in the lowest life space group. Social participation within a limited life space with activities may prevent disability onset. Geriatr Gerontol Int 2024; 24: 609-618.

Few studies have reported an association between diversity in productive activities and life satisfaction; hence, this cross-sectional study conducted in Japan aimed to clarify this association. We assessed the life satisfaction of 4,498 Japanese community-dwelling older adults engaged in productive activities (e.g., paid work, volunteering, taking care of children, and supporting others) using the Life Satisfaction Scale. We took the sum of the number of engaging productive activities as the diversity in productive activities score. A dose-response relationship was observed for each additional productive activity on life satisfaction. Participants who engaged in one, two, three, or four productive activities were more likely to have higher life satisfaction than those who did not engage; the odds ratios (95 % confidence intervals) were 1.19 (1.02-1.39), 1.19 (1.00-1.42), 1.71 (1.37-2.13), and 2.27 (1.58-3.27), respectively. Diversity in productive activities may enhance higher life satisfaction likelihood among Japanese community-dwelling older adults.

OBJECTIVE: This prospective cohort study investigates the relationship between the onset of disability and employment status. METHODS: We investigated 3,741 community-dwelling adults aged 70 or older, who participated in a population-based cohort study in Japan. Their onset of disability was monitored monthly using the long-term care insurance certification registration system, for five years from baseline. Based on an employment status questionnaire, we categorized participants into three groups: (1) employee, (2) self-employed, and (3) not working. Covariates included demographic information, medical history, number of medications, educational level, living alone, social group engagement, smoking status, walking speed, instrumental activities of daily living, global cognitive function, and depressive symptoms. Missing values were managed using multiple imputation. Cox proportional hazard models were used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) for incident disability risk by employment status. RESULTS: The disability incidence rates were 15.3/1,000 (95% CIs: 10.7-22.0) person-years among employees, and 33.0/1000 (95% CIs: 24.4-44.6) and 39.6/1000 (95% CIs: 36.5-43.0) person-years among self-employed and non-working participants, respectively. The adjusted HRs for the onset of disability among non-working and self-employed participants were 1.69 (95% CIs: 1.16-2.46, p = 0.007) and 1.63 (95% CIs: 1.01-2.62, p = 0.044) compared with employees, respectively. Similar results were found among men. Among women, disability onset was not associated with employment status. CONCLUSIONS: Older adults' risk of disability onset differed according to their employment status. Older employees had a lower risk of disability onset than those not working or self-employed.

BACKGROUND: Physical, cognitive, and psychological functions contribute to disability risk and are interrelated. This study explored the association between multidomain functional dispersion and disability-free survival in community-dwelling older adults. METHODS: This cohort study used NCGG-SGS data. Functional dispersion was the within-person SD across standardized physical, cognitive, and psychological domain scores; higher values indicated greater between-domain differences. Disability-free survival was time to first certification under the Japanese Long-Term Care Insurance system. Adjusted cause-specific Cox models with restricted cubic splines examined dispersion and incident disability, including mean functional score. Robustness was assessed using bootstrap, Fine-Gray, and log-transformed sensitivity analyses. RESULTS: Among 13,746 participants (baseline 2011-2017), 2,135 developed disability during 5 years (15.5%). Dispersion was non-linearly associated with disability risk (P for non-linearity <0.0001). Using the cohort median dispersion as the reference, adjusted hazard ratios were 0.94 (95% CI, 0.90-0.98) at the 25th percentile and 1.11 (95% CI, 1.03-1.20) at the 75th percentile. Below the median, hazard ratios decreased as dispersion declined, but rose again at the extreme lower tail. Above the median, risk rose modestly and then declined at higher dispersion. Bootstrap and Fine-Gray analyses supported these patterns. CONCLUSIONS: Multidomain functional dispersion showed a non-linear association with disability risk. Multidomain functional dispersion may be useful as an exploratory indicator of heterogeneity in disability risk beyond overall functional level.

INTRODUCTION: Cognitive function is associated with mortality in older adults, but the relative strength across cognitive assessment tools remains unclear, complicating population-level risk screening. The Mini-Mental State Examination is widely used but is limited by ceiling effects and educational bias. This study compared the associations of Mini-Mental State Examination and the Japanese Cognitive Function Test, a digital assessment, with all-cause mortality in a community-based cohort. METHODS: A cohort study was conducted among older adults in the National Center for Geriatrics and Gerontology-Study of Geriatric Syndromes in Japan. Participants aged ≥65 years completed the Mini-Mental State Examination and Japanese Cognitive Function Test at baseline during 2015-2018; data were analyzed in 2025. Cox proportional hazards models estimated hazard ratios for mortality, with exposures analyzed as both continuous and categorical variables. The duplication method tested the differences between the 2 tests. RESULTS: Among 9,514 participants (mean age of 72.9; 55% female), 588 (6.2%) died. Higher scores on both tests were inversely associated with mortality, but the associations were stronger for Japanese Cognitive Function Test. In continuous analyses, adjusted hazard ratios were 0.64 (0.54-0.77) for Mini-Mental State Examination and 0.44 (0.36-0.55) for Japanese Cognitive Function Test (p<0.001). In quintile analyses, hazard ratios for the highest versus the lowest quintile were 0.70 (0.52-0.93) and 0.37 (0.26-0.54). Stronger associations for Japanese Cognitive Function Test were more pronounced among participants with preserved baseline cognition (Mini-Mental State Examination≥24). CONCLUSIONS: Mini-Mental State Examination and Japanese Cognitive Function Test were inversely associated with 5-year mortality, but the association was stronger for Japanese Cognitive Function Test. Japanese Cognitive Function Test captured mortality risk even among those with preserved cognition, supporting its potential as a community-level tool for public health in older adults.

BACKGROUND: Cognitive frailty (CF) is recognized as a high-risk state for dementia, defined by the coexistence of physical frailty (PF) and mild cognitive impairment (MCI). While both PF and MCI increase vulnerability to dementia, CF confers an even higher risk than either condition alone. However, the neural substrates distinguishing CF from MCI remain unclear. The objective of this study is to elucidate the neural differences between CF and MCI using multimodal MRI analyses. METHODS: We investigated the neural substrates of community-dwelling older adults with CF (n = 61) and MCI (n = 108) by performing between-group comparisons of multimodal MRI measures to comprehensively examine the underlying neural mechanisms. Whole-brain analyses were conducted to assess gray matter (GM) volume, white matter hyperintensities (WMHs), and both structural and resting-state functional connectivity. Age, sex, vascular risk factors, and intracranial volume were included as covariates. RESULTS: The CF group exhibited significantly greater GM atrophy than the MCI group in widespread brain regions, including the temporal lobe, fusiform gyrus, cerebellum, cuneus, precuneus, precentral and postcentral gyri, and caudate nucleus. In contrast, no significant differences were observed between groups in WMH volume or count, structural connectivity, or resting-state functional connectivity. CONCLUSIONS: These findings suggest that widespread GM atrophy may be more evident in CF than in MCI, whereas no clear differences were observed in WMHs or structural or functional connectivity. This study provides new evidence on the neural basis of CF and highlights the utility of multimodal MRI in elucidating the neural substrates of frailty states.

BACKGROUND: The diagnosis of sarcopenic obesity has been established in Europe and Japan, but screening tools remain inconsistent and lack standardization. The fat-to-muscle ratio (FMR) is a potential screening measure for sarcopenic obesity; however, its diagnostic accuracy compared with other tools has not been evaluated. This study compared the diagnostic performance of several screening tools for sarcopenic obesity. METHODS: This cross-sectional analysis used data from the National Center for Geriatrics and Gerontology Study of Geriatric Syndromes (NCGG-SGS), a national cohort study conducted in Japan. In total, 7916 community-dwelling older adults (mean ± standard deviation age 73.5 ± 6.2 years, 54.8% females) were included. Sarcopenic obesity was diagnosed by the Japanese Working Group on Sarcopenic Obesity (JWGSO) criteria. The FMR and phase angle (PhA) were measured using the bioelectrical impedance analysis (BIA). RESULTS: Logistic regression analysis indicated that most screening tools, treated as continuous variables, were independently associated with sarcopenic obesity after adjustment for covariates; FMR (female: per 1-SD odds ratio [OR] = 3.06, 95% confidence interval [CI] = 2.53-3.71; male: OR = 3.09, 95% CI = 2.67-3.58), BMI (female: OR = 2.85, 95% CI = 2.35-3.58; male: OR = 1.43, 95% CI = 1.26-1.62), waist circumference (WC) (female: OR = 2.26, 95% CI = 1.86-2.74; male: OR = 1.24, 95% CI = 1.08-1.41) and PhA (female: OR = 1.12, 95% CI = 0.93-1.34; male: OR = 0.65, 95% CI = 0.56-0.76). Receiver operating characteristic (ROC) analysis showed moderate predictive ability for each screening tool: FMR (female: area under the curve [AUC] = 0.82, 95% CI = 0.79-0.85; male: AUC = 0.81, 95% CI = 0.79-0.84), BMI (female: AUC = 0.76, 95% CI = 0.72-0.79; male: AUC = 0.55, 95% CI = 0.51-0.59), WC (female: AUC = 0.70, 95% CI = 0.66-0.75; male: AUC = 0.53, 95% CI = 0.49-0.57) and PhA (female: AUC = 0.63, 95% CI = 0.58-0.69; male: AUC = 0.70, 95% CI = 0.67-0.74). CONCLUSIONS: The findings suggest that the FMR is a more effective screening tool for identifying sarcopenic obesity than BMI, WC or PhA among community-dwelling older adults. Longitudinal studies are needed to confirm its predictive value across broader populations.

BACKGROUND: We aimed to develop and validate a multivariable model for predicting dropout from a community-based going-out program for older adults. METHODS: The National Center for Geriatric and Gerontology's Study of Geriatric Syndromes, with a prospective cohort of general older adults, was employed. A total of 5905 older adults who were independent in their activities of daily living were recruited and randomly allocated into training, validation, and testing data sets in a 6:2:2 ratio. An outcome was defined as dropping out of a community-based going-out program within 180 days. An extreme gradient boosting algorithm was used to develop the predictive model using training and validation data sets and to identify feature importance. The model's discrimination and calibration were evaluated in the test data set. RESULTS: The area under the curve for the receiver operating characteristic ( 95% CI) was 0.701 (0.670-0.732). Sensitivity, specificity, positive predictive value, and negative predictive value and their 95% CIs were 0.253 (0.226-0.277), 0.915 (0.899-0.931), 0.588 (0.560-0.612), and 0.718 (0.692-0.743), respectively, and the slope of the calibration plot was 1.046 (0.909-1.182). Cognitive and physical functions and willingness to engage in exercise/sport activities were selected as the most important features. CONCLUSIONS: The predictive model reliably indicates whether a participant will drop out when classified as negative but not when classified as positive. Physical and cognitive functions and willingness to engage in physical activity may be primary predictors.

OBJECTIVES: With dementia prevalence rising globally among older adults, effective and scalable community-based interventions are urgently needed to reduce dementia onset. This study aimed to estimate the association of the going-out program with dementia onset in older adults. METHODS: A 5-year longitudinal observational study was employed. Following a baseline assessment in 2015 and 2017, we observed 2,977 individuals engaging in a community-based going-out program for 12 months in Japan. Participants with continuous data over 12 months were defined as the engaged group, while those without such data were classified as the non-engaged group. After propensity score matching, 1,690 participants were selected. Dementia onset was obtained from the Japanese National Health Insurance and Later-Stage Medical Care System for 48-month follow-up. Incidence of dementia, absolute risk reduction (ARR), and number needed to treat (NNT) were calculated. The Cox proportional hazards model was used to estimate the effect of engagement in the program on dementia onset and to calculate a hazard ratio and 95 % confidential interval (CI). RESULTS: The incidence of dementia onset was 59 out of 845 (7.0 %) in the non-engagement group and 34 out of 845 (4.0 %) in the engagement group. The ARR rate was 3.0 % (95 % CI 0.8, 5.2), and the NNT was 33 (95 % CI 19, 125). The hazard ratio was 0.57 (95 % CI 0.37, 0.86). DISCUSSION: Engagement in the going-out program resulted in a 3.0 % reduction in the risk of dementia onset. The going-out program, which can be implemented in communities, holds potential efficacy in preventing dementia onset.

OBJECTIVES: This study examined the association between polypharmacy and incident disability across the dietary variety score (DVS) strata among community-dwelling older adults. STUDY DESIGN: A prospective cohort study with community-dwelling adults aged ≥65 in Aichi, Japan. MAIN OUTCOME MEASURES: Polypharmacy was defined as ≥5 concomitant prescription drugs per day. Participants were classified as having non-polypharmacy or polypharmacy and a lower, moderate, or high DVS. Cox proportional hazard regression models were used to estimate hazard ratios (HRs) with 95 % confidence intervals (CIs) for incident disability among the polypharmacy groups after adjusting for potentially confounding variables. RESULTS: The analysis included 5254 older adults (55.7 % female; average age 74.0 ± 5.5 years) with a mean follow-up time of 34.7 ± 5.9 months. Among them, 4842 remained disability-free, while 412 (7.8 %) developed a disability during follow-up. The potential confounder-adjusted disability HR for participants in the polypharmacy group was 1.37 (CI: 1.07-1.75; p = 0.011). In the stratified analyses, polypharmacy in the lower DVS group was significantly associated with higher HRs for incident disability (1.62 [1.11-2.37; p = 0.013]), and no significant association between polypharmacy and incident disability was observed in the higher DVS group (1.12 [0.74-1.71; p = 0.590]). CONCLUSIONS: Polypharmacy was positively associated with disability incidence, with a more pronounced effect in participants with a lower DVS. Polypharmacy patients may have different reasons for not being able to have a higher variety diet from non-polypharmacy people.

INTRODUCTION: In efforts to address the public health concern of physical frailty prevention, community-based programs without supervision are anticipated, yet efficacy has not been shown. We aimed to investigate the association of engaging in an unsupervised, community-based going-out program on the incidence of physical frailty among older adults. METHODS: A cohort observational study was employed. Following a baseline assessment during 2015 and 2017 in Japan, we observed 1,350 older adults engage in a community-based going-out program for 12 months. Participants were categorized into either a non-engaged or engaged group via propensity score matching. A follow-up survey (mean period = 920 ± 76 days) was conducted to investigate the occurrence of physical frailty using the Kihon Checklist. The incidence of frailty, absolute risk reduction, and number needed to treat for program engagement were calculated. The odds ratio (OR) in engaged group compared with the non-engaged group was determined in a logistic regression model. RESULTS: Incidence of frailty was 15.1% in non-engaged group (n = 107 out of 628) and 8.3% in the engaged group (n = 53 out of 628). The number needed to treat and its 95% confidence interval were 21 (12-63) after matching. Compared with matched non-engaged group (OR 1.0), the OR and 95% confidence interval of matched engaged group for occurrence of physical frailty were 0.61 (0.42-0.87). CONCLUSIONS: Engaging in the unsupervised community-based going-out program could prevent one incidence of physical frailty in every 21 participants and may thus contribute to preventing physical frailty at the population level.

Abstract Background Cognitive reserve (CR) is a property of the brain trait that allows for better–than–expected cognitive performance, relative to the degree of brain change over the life course. However, the neurophysiological markers of CR require further investigation. Electroencephalography (EEG) may provide an appropriate neurophysiological marker of CR. Therefore, we tested whether activity in the dorsal attention network (DAN) and the ventral attention network (VAN), as measured during resting–state EEG, moderates the relationship between hippocampal volume and episodic memory. Method Participants from the National Center for Geriatrics and Gerontology–Study of Geriatric Syndromes, were included; all underwent determined hippocampal volume using MRI and episodic memory was measured using word lists. After testing the effect of hippocampal volume on memory performance using multiple regression analysis, we evaluated the interactions between hippocampal volume and DAN and VAN network activity. We used the Johnson–Neyman technique to quantify the moderating effects of the DAN and VAN network activity on the relationship between hippocampal volume and word list memory, and to identify specific ranges of the DAN and VAN network activity with significant hippocampal–memory associations. Result A total of 449 participants were included in this study. We found significant moderation of DAN with a slope of β = ‐0.0001 (95% CI: ‐0.0002; ‐0.00001, p = 0.041) and VAN was significant, with a slope of β = 0.0001 (95% CI: 0.00001; 0.0003, p = 0.032). We found that larger hippocampal volume was associated with better memory performance, and this association became stronger the lower the DAN activity. However, when the DAN activity was &gt; 944.9, the hippocampal volume was no longer significantly related to word list memory performance. For VAN, we found higher hippocampal volume was more strongly associated with better memory performance when VAN activity was higher. However, when the VAN activity was &lt; 914.6, the hippocampal volume was no longer significantly associated with word list memory. Conclusion Our results suggest that attention network helps maintain memory performance in the face of age related structural decline, meeting criteria for a neural implementation of cognitive reserve.

BACKGROUND: A previous study suggested older drivers with subjective memory concerns (SMC) had increased odds of experiencing car collisions, but whether SMC in different contexts and the number of SMC applicable items change this association is unknown. The aim of this study was to examine the association between SMC and car collisions among older drivers in Japan. METHODS: This cross-sectional study was conducted using data from a Japanese community-based cohort study. Participants were community-dwelling older adults aged ≥60 years. SMC was assessed using five questions: 1) "Do you feel you have more problems with memory than most?" 2) "Do you have any difficulty with your memory?" 3) "Do you forget where you have left things more than you used to?" 4) "Do you forget the names of close friends or relatives?" and 5) "Do other people find you forgetful?" Participants were asked about their experiences with car collisions during the previous two years. RESULTS: A total of 13,137 older drivers (72.1 ± 5.5 years old, and 43.6 % female) were analyzed. Cochran-Armitage trend test showed that as the number of SMC applicable items increased, the percentage of the experiences of car collisions significantly increased (6.8 %-15.8 %, P < 0.001). Logistic regression models showed each SMC question was associated with an increased odds ratio (OR) of car collisions (OR 1.26 to 1.71, all P < 0.001) after adjusting for confounding factors. As the number of SMC applicable items increased, the OR of car collisions significantly increased (OR 1.19 to 2.28, all P < 0.05, P for trend <0.001). CONCLUSIONS: This cross-sectional study among community-dwelling older drivers in Japan suggested each SMC question and the number of applicable items were associated with car collisions. SMC may be a sign of increased risk of traffic incidents for older drivers.

PURPOSE: Sarcopenic obesity is a combination of sarcopenia and obesity, which is associated with the onset of disability. Fat to muscle ratio (FMR) is a screening measure that assesses the ratio of muscle mass to fat mass. However, the relationship between the FMR and disability has not been investigated. METHODS: This study included 11,427 community-dwelling older adults aged ≥65 years enrolled in NCGG-SGS (National Center for Geriatrics and Gerontology-Study of Geriatric Syndromes), a national cohort study in Japan. FMR was measured by the bioelectrical impedance analysis and calculated by dividing fat mass by muscle mass. Cox proportional hazard regression analysis adjusted for covariates was used to investigate the association between FMR and the risk of developing new care needs at 5 years. FMR was divided by about quintile, with quintile 5 as the high. RESULTS: The high FMR group had the highest incidence of disability at 20.8 % for women and 20.1 % for men. In women, the association between FMR and disability was significantly different for the FMR (hazard risk [HR]: 1.43, 95 % confidence interval [CI]: 1.16-1.75). There was no association between FMR and disability in men (HR: 0.98, 95 %CI: 0.76-1.25). Lagged analyses accounting for reverse causality did not change the relationship. CONCLUSIONS: FMR is associated with increased risk of disability in women community-dwelling older adults but not among men. Because the rate of decreased muscle strength is faster in men than in women, early decreased muscle strength may affect men's risk of disability more than muscle mass or fat mass.

OBJECTIVES: Although going out has been reported to be associated with the incidence of disability, few studies have investigated the effect of community-based programs to promote going out on the incidence of disability. This study aimed to estimate the effects of a program fostering going-out on the incidence of disability in community-dwelling older adults. DESIGN: Longitudinal, observational study. SETTING AND PARTICIPANTS: Nonengaged (n = 1086) and engaged older adults (n = 1086) enrolled in the National Center for Geriatrics and Gerontology Study of Geriatric Syndrome by using a one-to-one nearest neighbor propensity score-matching scheme. METHODS: After the baseline assessments, participants in the community-based going-out program received a specialized physical activity tracker, monitored their daily physical activity, and received personalized feedback on going out to community facilities with a system for reading the device for 12 months. Disability onset was defined as a new case of long-term care under the public insurance certification in Japan within 48 months of program completion. The absolute risk reduction and the number needed to treat for the incidence of disability were calculated for the nonengaged and engaged groups. Cox proportional hazard regression analysis, using inverse probability weighting was used to obtain the hazard ratio. RESULTS: Disabilities occurred in 112 individuals in the matched nonengaged group and 51 individuals in the engaged group. The absolute risk reduction was 5.67% (95% CI 3.46%-7.88%). The number needed to treat was 18 (95% CI 13-29). The hazard ratio, with the nonengaged group as the reference, was 0.49 (95% CI 0.36-0.67). CONCLUSIONS AND IMPLICATIONS: This longitudinal observational study suggested that a community-based program could prevent 1 disability in every 18 participants. This program does not require a professional instructor, only the distribution of devices and system installation, and it could be beneficial as a population-based approach to preventing disabilities.

OBJECTIVES: This longitudinal observational cohort study aimed to clarify the relationship between perceived value (PV) to adopt new behaviors and incident disability in community-dwelling older adults. METHOD: Participants were 5073 community-dwelling older adults aged ≥65 years in Japan (Mage = 74.0 ± 5.6 years; female = 55.1%). The mean follow-up time was 34.5 months. Baseline data were collected during health checkups in a prospective cohort study. Measurements included engagement in physical activity (PA), cognitive activity (CA), and social activity (SA), PV, health and physical conditions, and demographic characteristics. PV was assessed by asking whether participants thought it was valuable to adopt new behaviors related to PA, CA, and SA. Participants were classified as having higher/lower PV, PA, CA, and SA. Cox proportional hazard models were used to analyze the association between PV and incident disability. PV was examined both as an independent variable and in combination as follows: higher PV and higher PA/CA/SA (high/high); lower PV and higher PA/CA/SA (low/high); higher PV and lower PA/CA/SA (high/low); and lower PV and lower PA/CA/SA (low/low). RESULTS: Higher PV was significantly associated with a lower hazard ratio (HR) for incident disability. The low/high, high/low, and low/low significantly increased the HR compared to high/high in the analyses of PV & PA and CA. The analysis of PV & SA showed that only low/low increased the HR compared to high/high. CONCLUSION: Having both higher PV and higher activity engagement may contribute to preventing disability development. Both support for activities and value education in older adults may be needed.

PURPOSE: This study aimed to investigate association between objectively measured physical activities with incidence disability in older adults with and without social isolation. METHODS: This 5-year longitudinal observational study used a population-based study from a sub-cohort of the National Center for Geriatrics and Gerontology Study of Geriatric Syndrome. In Japan, Incident disability is defined as a new case of public insurance certification for long-term care. As participants, we enrolled 5,257 community-dwelling older adults aged ≥ 70 years. The Participants on whom incomplete baseline physical activity assessments were performed; who required long-term care; had a history of dementia, Parkinson's disease, stroke, or depression; who lacked independence in basic ADL; who had Mini-Mental State Examination scores; or who had missing measurements; were excluded. Thus, 2,071 participants were included. RESULTS: Of the participants, 1,183 non-socially isolated participants had 151 (4.3%) cases of disability, while socially isolated participants had 150 (13%) cases. Cox proportional-hazards regression analysis presented the adjusted hazard ratio (HR) and 95% confidence interval (95%CI) of daily steps and low-intensity and moderate-to-vigorous physical activities-0.62(0.43-0.89), 0.84(0.60-1.18), 0.62(0.43-0.89) in participants with social isolation, and 0.58(0.40-0.85), 0.86(0.60-1.24), 0.70(0.49-1.01) in those with social isolation. CONCLUSIONS: Daily steps were significantly associated with a decreased risk of incidence disability, regardless of social isolation. These results suggest the greater importance of daily physical activity than its specific intensity in socially isolated older adults.

The purpose of this study was to conduct a cross-sectional analysis of the association between hearing aid use and cognitive decline in community-dwelling older adults with hearing impairment, stratified by cardiovascular risk level. This cross-sectional study covers 1857 hearing-impaired individuals selected among 10,674 community-dwelling older adults (≥65 years of age) in Japan. We investigate the association between hearing aid use and cognitive decline stratified by cardiovascular risk level, by assessing self-reported hearing impairment and hearing aid use, absolute cardiovascular risk, cognitive function, and potential confounding factors. The association between hearing impairment severity and increased cardiovascular risk, and the benefit of hearing aid use in preventing cognitive decline, were examined in a binomial logistic regression analysis, with the presence of cognitive decline as the objective variable. In the low cardiovascular risk group, hearing aid users had a lower odds ratio for decline in executive function than non-users (odds ratio = 0.61, 95% confidence interval: 0.39-0.98). However, there was no significant association between hearing aid use and cognitive decline in the high cardiovascular risk group (p > 0.05). Among older adults with hearing impairment, hearing aid use was associated with the maintenance of executive function in individuals of low cardiovascular risk.

OBJECTIVES: Regular physical activity throughout life is generally recommended to prevent dementia; however, there is little evidence regarding the association between lifetime physical activity and mild cognitive impairment (MCI), which often precedes dementia. This study aimed to examine the association of lifetime physical activity and their transitions with late-life MCI. DESIGN: A population-based case-control study. SETTING AND PARTICIPANTS: A total of 2968 Japanese community-dwelling older adults aged ≥70 years without dementia. METHODS: We evaluated the participants' early-, mid-, and late-life physical activity habits and categorized their transitions across life stages. Cognitive functions in late life were assessed for memory, attention, executive function, and processing speed; functional impairment in one or more cognitive domains was defined as MCI. RESULTS: Regular physical activity in early life was not significantly associated with late-life MCI [odds ratio (OR), 0.80; 95% CI, 0.63-1.02], although those in mid-life (OR, 0.64; 95% CI, 0.51-0.81) and late-life (OR, 0.74; 95% CI, 0.59-0.91) were associated with lower odds of late-life MCI. Compared with nonexercisers, participants who acquired new habits of physical activity during mid- or late-life (OR, 0.71; 95% CI, 0.55-0.91) and those who maintained physical activity throughout their life span (OR, 0.61; 95% CI, 0.42-0.87) had lower odds of late-life MCI; those who stopped regular activity during mid- or late-life did not (OR, 0.79; 95% CI, 0.58-1.06). CONCLUSIONS AND IMPLICATIONS: While physical activity throughout the life span is associated with the lowest odds of MCI, starting regular physical activity, even later in life, confers a benefit and should be encouraged as a "lifelong approach" to MCI risk reduction.

Early preventive measures against depression have become important with unprecedented global aging. Increase in one's perceived value (PV) may correspond to better mental health outcomes. This cross-sectional observation study aimed to clarify whether the PV of adopting new behaviors is associated with depressive symptoms. The participants were 5266 community-dwelling older adults aged ≥ 65 years. We developed a questionnaire to measure the PV of adopting new behaviors, specifically activities beneficial for preventing depressive symptoms (physical, cognitive, and social activities) in older adults. The questionnaire asked whether adopting the ten selected behaviors was valuable. The scores were added, and the total score ranged from - 20 to 20. The odds ratios (OR) of depressive symptoms were calculated using binomial logistic regression according to the PV score quartiles. Depressive symptoms were reported by 595 (11.3%) participants. After adjusting for potential confounders, higher quartiles of PV scores were significantly associated with lower prevalence of depressive symptoms: vs Q1; Q2 OR 0.76 (95% confidence interval: 0.59-0.97); Q3 0.67 (0.51-0.87); Q4 0.54 (0.40-0.73) (P for trend < .001). Having a higher PV of adopting new behaviors may prevent depressive symptoms among older adults. Healthcare professionals need to pay attention to poor value orientation among older adults.

BACKGROUND AND OBJECTIVES: Cognitive reserve (CR) is a property of the brain that allows for better-than-expected cognitive performance relative to the degree of brain change over the course of life. However, neurophysiological markers of CR remain under-investigated. Electroencephalography (EEG) features may function as suitable neurophysiological markers of CR. To assess this, we investigated whether the dorsal attention network (DAN) and ventral attention network (VAN) activities, as measured during resting-state EEG, moderate the relationship between hippocampal volume and episodic memory. METHODS: Participants were recruited as part of the National Center for Geriatrics and Gerontology-Study of Geriatric Syndromes. Hippocampal volume was determined using magnetic MRI, and episodic memory was measured using word lists. After testing the effect of hippocampal volume on memory performance using multiple regression analysis, we evaluated the interactions between hippocampal volume and DAN and VAN network activities. We further used the Johnson-Neyman technique to quantify the moderating effects of DAN and VAN network activities on the relationship between hippocampal volume and word list memory, as well as to identify specific ranges of DAN and VAN network activity with significant hippocampal-memory association. RESULTS: A total of 449 participants were included in this study. Our analysis revealed significant moderation of DAN with a slope of β = -0.00012 (95% CI: -0.00024; -0.00001, p = 0.040), and VAN with a slope of β = 0.00014 (95% CI: 0.00001; 0.00026, p = 0.031). Further, we found that a larger hippocampal volume was associated with improved memory performance, and that this association became stronger as the DAN activity decreased until a limit of DAN activity of 944.9, after which the hippocampal volume was no longer significantly related to word-list memory performance. For the VAN, we found that a higher hippocampal volume was more strongly associated with better memory performance when VAN activity was higher. However, when VAN activity extended beyond -914.6, the hippocampal volume was no longer significantly associated with word-list memory. DISCUSSION: Our results suggest that attentional networks help to maintain memory performance in the face of age-related structural decline, meeting the criteria for the neural implementation of cognitive reserve.

PURPOSE: Delaying the onset of disabilities is a social challenge, especially in an aging society. Social isolation (SI) and metabolic syndrome (MetS) can coexist and pose the risks of disability onset. However, their interaction is not proven in older adults. Therefore, this study investigated whether SI combined with MetS exacerbates disability onset in older adults. MATERIALS AND METHODS: A total of 3,738 community-dwelling older adults underwent a health check-up. After baseline assessments, we followed them up to assess disability incidence for five years. SI was defined as a condition in which two or more of the following measures were met: domestic isolation, less social contact, and social disengagement. MetS was defined according to the criteria of the International Diabetes Federation. We used Cox proportional hazard regression used to identify the interaction effect of SI and MetS on the risk of disability onset after adjusting for potential confounding factors. RESULTS: Multivariate Cox proportional hazard regression showed a significant interaction effect of SI and MetS on disability onset. In the subgroup analysis stratified by MetS status, SI was identified as a risk factor for disability onset only in the MetS group, but not in the non-MetS group. CONCLUSIONS: This five-year longitudinal study showed that the co-occurrence of SI and MetS increased the risk of disability onset in older adults. This indicates that the assessment of MetS in socially isolated older adults is important for healthcare providers to delay the onset of disabilities.

BACKGROUND: Neurodegeneration and structural changes in the brain due to amyloid deposition have been observed even in individuals with mild cognitive impairment (MCI). EEG measurement is considered an effective tool because it is noninvasive, has few restrictions on the measurement environment, and is simple and easy to use. In this study, we investigated the neurophysiological characteristics of community-dwelling older adults with MCI using EEG. METHODS: Demographic characteristics, cognitive function, physical function, resting-state MRI and electroencephalogram (rs-EEG), event-related potentials (ERPs) during Simon tasks, and task proportion of correct responses and reaction times (RTs) were obtained from 402 healthy controls (HC) and 47 MCI participants. We introduced exact low-resolution brain electromagnetic tomography-independent component analysis (eLORETA-ICA) to assess the rs-EEG network in community-dwelling older adults with MCI. RESULTS: A lower proportion of correct responses to the Simon task and slower RTs were observed in the MCI group (p < 0.01). Despite no difference in brain volume between the HC and MCI groups, significant decreases in dorsal attention network (DAN) activity (p < 0.05) and N2 amplitude of ERP (p < 0.001) were observed in the MCI group. Moreover, DAN activity demonstrated a correlation with education (Rs = 0.32, p = 0.027), global cognitive function (Rs = 0.32, p = 0.030), and processing speed (Rs = 0.37, p = 0.010) in the MCI group. The discrimination accuracy for MCI with the addition of the eLORETA-ICA network ranged from 0.7817 to 0.7929, and the area under the curve ranged from 0.8492 to 0.8495. CONCLUSIONS: The eLORETA-ICA approach of rs-EEG using noninvasive and relatively inexpensive EEG demonstrates specific changes in elders with MCI. It may provide a simple and valid assessment method with few restrictions on the measurement environment and may be useful for early detection of MCI in community-dwelling older adults.

OBJECTIVE: Both physical and social frailty are risk factors for major adverse health-related outcomes and influence each other. However, the longitudinal causal relationship between physical and social frailty has not been clarified. This study aimed to determine the reciprocal relationship between physical and social frailty by age group. METHODS: This study analyzed longitudinal data from a cohort study of older adults aged 65 years or older living in Obu City, Aichi Prefecture, Japan. The study included 2568 participants who participated in both a baseline assessment in 2011 and a follow-up assessment four years later. Participants participated in assessments of physical and cognitive function. Physical frailty was assessed using the Japanese version of the Cardiovascular Health Study criteria. Social frailty was assessed with five questions about daily social activities, social roles, and social relationships. A total frailty score was calculated for each frailty type and used in the cross-lagged panel analysis. The reciprocal relationship between physical and social frailty status was analyzed using a cross-lagged panel model in each of the young-old (n = 2006) and old-old (n = 562) groups. RESULTS: In the old-old group, baseline physical frailty status predicted social frailty status four years later, and social frailty status at baseline predicted physical frailty status four years later. In the young-old group, the effect of social frailty status at baseline on physical frailty at four years was significant; however, the cross-lag effect from baseline physical frailty status to social frailty status at four years was insignificant, indicating that social frailty preceded physical frailty. CONCLUSION: The reciprocal relationship between physical and social frailty differed by age group. The results of this study suggest the importance of considering age when planning strategies to prevent frailty. Although a causal relationship between both physical and social frailty was observed in old-old, social frailty preceded physical frailty in the young-old, suggesting that early prevention of social frailty is important for the prevention of physical frailty.

OBJECTIVES: Previous studies have indicated that sarcopenic obesity is a risk factor for disability onset. However, these studies had disparities in terms of criteria for sarcopenia, study design, or study population. No longitudinal study has investigated the effect of sarcopenic obesity on disability onset in an Asian population using the Asian Working Group for Sarcopenia 2019 criteria for sarcopenia definition. Herein, we aimed to investigate the longitudinal effect of sarcopenic obesity on disability onset in Japanese older adults and extend the generalizability of results to other populations. DESIGN: Longitudinal cohort study. SETTING AND PARTICIPANTS: A total of 4197 Japanese older adults (mean age 74.6 ± 5.0 years, 54.2% women) formed our study population. MEASUREMENTS: Sarcopenia was identified using the Asian Working Group for Sarcopenia 2019 algorithm. Obesity was determined when body fat percentage was ≥25%, or when visceral fat content was ≥100 cm2 for either sex. Disability onset was defined as a new case of long-term care insurance system certification for 5 years from baseline. Missing values were managed with multi-imputation. Cox proportional hazard regression analysis was used with disability onset as dependent variable and group (nonsarcopenia/nonobesity as a reference, nonsarcopenia/obesity, sarcopenia/non-obesity, possible sarcopenia/obesity, possible sarcopenia/non-obesity, sarcopenic obesity) as explanatory variable, and was adjusted for potential confounding factors. RESULTS: When the nonsarcopenia/nonobesity group was used as the reference category, other groups such as possible-sarcopenia/nonobesity [hazard ratio (HR) 1.38, 95% confidential interval (95% CI) 1.29‒1.47, P < .028], possible-sarcopenia/obesity (HR 1.54, 95% CI 1.46‒1.62 P < .001), sarcopenia/nonobesity (HR 2.09, 95% CI 1.96‒2.23, P < .001), and sarcopenic obesity (HR 2.48, 95% CI 2.24‒2.75, P < .001) showed significantly increased HRs. CONCLUSIONS AND IMPLICATIONS: The risk of disability onset because of sarcopenic obesity was exceedingly higher compared with sarcopenia alone among community-dwelling older adults in Japan The health providers should consider assessing the co-existence of sarcopenia and obesity to screen for the risk of disability onset in the community-dwelling population.

IMPORTANCE: To prevent motor vehicle collisions by older drivers, the increased risk of collisions should be considered early. Cognitive decline increases the risk of car collisions. Motoric cognitive risk syndrome (MCR), characterized by the presence of cognitive concerns and slow gait, can be assessed conveniently and is useful to assess the risk of dementia. OBJECTIVE: To examine the association between MCR assessment findings and car collisions among older drivers in Japan. DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study used data from a community-based cohort study, the National Center for Geriatrics and Gerontology-Study of Geriatric Syndromes, conducted in Japan from 2015 to 2018. Participants were community-dwelling older adults aged at least 65 years. Data were analyzed from February to March 2023. EXPOSURE: MCR was defined as having subjective memory concerns (SMC) and slow gait. Participants were classified into 4 groups: no SMC or slow gait, only SMC, only slow gait, and MCR. MAIN OUTCOMES AND MEASURES: Participants were asked about the experience of car collisions during the last 2 years and near-miss traffic incidents during the previous year through face-to-face interviews. Odds of experiencing a collision or near-miss traffic incident were assessed using logistic regression. RESULTS: Among a total of 12 475 participants, the mean (SD) age was 72.6 (5.2) years, and 7093 (56.9%) were male. The group with only SMC and the group with MCR showed a higher proportion of both car collisions and near-miss traffic incidents than the other groups (adjusted standardized residuals > 1.96; P < .001). Logistic regression analysis showed the only SMC and MCR groups had increased odds of car collisions (only SMC group: odds ratio [OR], 1.48; 95% CI, 1.27-1.72; MCR group: OR, 1.73; 95% CI, 1.39-2.16) and near-miss traffic incidents (only SMC group: OR, 2.07; 95% CI, 1.91-2.25; MCR group: OR, 2.13; 95% CI, 1.85-2.45) after adjusting for confounding factors. After stratifying MCR assessments by objective cognitive impairment, significant associations were still observed. In the only slow gait group, objective cognitive impairment was associated with increased odds of car collisions (OR, 1.96; 95% CI, 1.17-3.28). CONCLUSIONS AND RELEVANCE: In this cross-sectional study of community-dwelling older drivers in Japan, SMC and MCR were associated with car collisions and near-miss traffic incidents independent from objective cognitive impairment. Future studies should examine the mechanism of these associations in more detail.

PURPOSE: Whether the combination of sarcopenia and systolic blood pressure (SBP) changes the risk of all-cause mortality is unknown. Thus, this study aimed to examine the association between sarcopenia and SBP in community-dwelling older adults and determine whether this association changes the mortality risk. METHODS: Older adults aged ≥65 years participated in the baseline assessment. The participants were classified into six groups according to a combination of the presence or absence of sarcopenia (sarcopenia, non-sarcopenia) and SBP (low SBP, ≤119 mmHg; normal SBP, 120-139 mmHg; high SBP, ≥140 mmHg). The participants were followed for the occurrence of death for 5 years after baseline assessment. Muscle mass, grip strength, and walking speed as indicators of sarcopenia, SBP, and all-cause mortality data for 5 years from baseline assessment were evaluated. RESULTS: This study included 13,569 community-dwelling older adults. During the 5-year follow-up period, 830 participants (6.6%) died. In the Cox proportional hazards models, the risk of all-cause mortality was higher in other non-sarcopenia groups than in the non-sarcopenia/normal SBP group. In particular, those with sarcopenia had a higher mortality risk. CONCLUSIONS: Low or high SBP increased the mortality risk in community-dwelling older adults. In those with sarcopenia, low or high SBP was associated with an even higher mortality risk. Older adults with sarcopenia and low/high blood pressure should be monitored as a population at a higher mortality risk.

IMPORTANCE: Loneliness is suggested to negatively affect physical and mental health and influence the development of disability; however, a consensus on the relationship between loneliness and disability has not been reached. Age-related hearing impairment worsens the daily-life activities of older adults, and the association between loneliness and the incidence of disability may be influenced by hearing impairment. OBJECTIVE: To examine the association between loneliness and the incidence of disability among older adults stratified by hearing impairment. DESIGN, SETTING, AND PARTICIPANTS: This prospective observational cohort study included 5563 community-dwelling adults 65 years or older who participated in functional health examinations in Tokai City, Aichi Prefecture, Japan, between September 2017 and June 2018. Data analysis was conducted from August 2022 to February 2023. MAIN OUTCOMES AND MEASURES: Cox proportional hazards regression models were used to examine the association between loneliness and the incidence of disability stratified by hearing impairment. RESULTS: Among the 4739 participants who met the inclusion criteria (mean [SD] age, 73.8 [5.5] years; 2622 [55.3%] female), 3792 (80.0%) were without hearing impairment and 947 (20.0%) were with hearing impairment. Of those who reported experiencing loneliness, 1215 (32.0%) were without hearing impairment, and 441 (46.6%) were with hearing impairment. After 2 years, the number of individuals with disabilities was 172 (4.5%) without hearing impairment and 79 (8.3%) with hearing impairment. Cox proportional hazards regression analysis showed no statistically significant association between loneliness and the incidence of disability in a model adjusted for potential confounding factors among community-dwelling older adults without hearing impairment (hazard ratio, 1.10; 95% CI, 0.80-1.52). Among community-dwelling older adults with hearing impairment, a model adjusted for potential confounding factors showed a statistically significant association between loneliness and the incidence of disability (hazard ratio, 1.71; 95% CI, 1.04-2.81). CONCLUSIONS AND RELEVANCE: This cohort study found that the association between loneliness and the incidence of disability was moderated by the presence or absence of hearing impairment. Hearing impairment is the most common symptom of geriatric syndromes, showing that among the various risk factors, loneliness may require special attention in the prevention of disability in people with hearing impairment.

INTRODUCTION: Delaying the onset of disability is important for maintaining independence and quality of life in community-dwelling older adults. Given that social isolation is a significant risk factor for disability, effective means associated with social isolation are needed to alleviate disability. Although information and communication technology (ICT) may be a reasonable measure considering the recent social contexts due to the coronavirus disease 2019 pandemic, further insights are required. This study aimed to investigate whether ICT use can alleviate the onset of disability in community-dwelling older adults with and without social isolation. METHODS: This longitudinal cohort study on 4,346 community-dwelling independent Japanese older adults (mean age, 73.5 ± 5.3 years) was conducted between 2017 and 2018. Participants were classified into four groups based on social isolation (the condition where two or more of the following measures were met: domestic isolation, less social contact, and social disengagement) and ICT users (those who had recently used a computer or a smartphone) and followed up to assess disability incidence for 24 months after baseline assessments. Cox proportional-hazards regression models were used to identify the effect of social isolation and ICT use on the risk of disability onset by adjusting for age, sex, education history, number of medications, eye disease, level of annual income, Mini-Mental State Examination, Geriatric Depression Scale 15, and gait speed. RESULTS: The group comprised nonsocial isolation and ICT users (44.7%), social isolation and ICT users (5.4%), nonsocial isolation and ICT nonusers (41.7%), and social isolation and ICT nonusers (8.2%). At the follow-up, 2.2%, 2.4%, 5.5%, and 12.4% of the participants in the above order developed disability (p < 0.01). Cox regression models revealed a significantly higher risk of disability onset in the social isolation and ICT nonusers group than in the social isolation and ICT users group (HR = 2.939; 95% confidence interval (CI) 1.029-8.397; p = 0.044). In the subgroup analysis stratified by social isolation, ICT use significantly reduced the risk of disability onset in the socially isolated group (HR = 0.320; 95% CI 0.109-0.943; p = 0.039), although the same association was not observed in the nonsocially isolated group (HR = 0.845; 95% CI 0.565-1.264; p = 0.411). CONCLUSION: ICT use can alleviate the onset of disability in socially isolated older adults in a community setting. Considering ICT-applied methods for alleviating disability is beneficial for older adults in social isolation.

Background: The characteristics of both straight- and curved-path walking abilities and walking self-efficacy among older women aged ≥ 75 years with high social functioning are not clear. This study aimed to clarify the characteristics of walking ability and self-efficacy among young-old (age 65-74 years) and old-old women (age ≥ 75 years) with high social functioning. Methods: The participants in this cross-sectional study were 36 community-dwelling older women (mean age ± standard deviation: 73.4 ± 5.2 years) recruited using a convenience sampling method. The 5-m and Figure-of-8 Walk Tests were used to evaluate straight- and curved-path walking abilities. Waking self-efficacy was evaluated using the modified Gait Efficacy Scale. The participants were divided into two age groups: 65-74 (n = 22) and ≥ 75 years (n = 14). The results of the 5-m and Figure-of-8 Walk Tests and the modified Gait Efficacy Scale were compared between groups using an unpaired t-test and the Mann-Whitney U test. The relationships between the evaluation items were analyzed using Pearson's product-moment correlation coefficient and Spearman's rank correlation coefficient. Results: Significant differences were found between the two groups in the 5-m Walk Test (p = 0.011) and Figure-of-8 Walk Test (p = 0.016)| however, no significant differences were seen in modified Gait Efficacy Scale scores (p = 0.311). The correlation coefficients between modified Gait Efficacy Scale scores and walking abilities were lower in the group aged ≥ 75 years. Conclusions: The present study found that, compared with women aged 65-74 years, those aged ≥ 75 years with high social functioning showed no decline in walking self-efficacy or straight- and curved-path walking abilities.