近藤 克則

Aim Long-term care systems may alleviate caregiver burdens, particularly for those with fewer resources. However, it remains unclear whether socioeconomic disparity in caregiver burdens exists under a public, universal long-term care insurance (LTCI) system. This study examined income-based inequalities in caregiving time and depressive symptoms in Japanese older family caregivers. We further compared inequality in depressive symptoms with that of non-caregivers to evaluate whether family caregiving exacerbates this disparity. Methods Data were obtained from a cross-sectional, nationwide survey conducted by the Japan Gerontological Evaluation Study in 2013. Participants were functionally independent older adults aged 65 years (N = 21,584). Depressive symptoms were assessed using the Geriatrics Depression Scale (GDS) caregiving hours per week, household income, and other covariates were also assessed. Results Family caregivers occupied 8.3% of the total. A Poisson regression model revealed that caregivers in lower income groups (compared to those in the highest) were 1.32 to 1.95 and 1.63 to 2.68 times more likely to engage in 36 and 72 hours/week of caregiving, respectively. As for the GDS (5), an excess risk was found in the caregivers in lower (compared to higher) income groups (adjusted prevalence ratio: 1.57–3.10). However, an interaction effect of income by caregiving role indicated no significant difference in inequality between caregivers and non-caregivers (p = .603). The excess risk for GDS (5) in the caregivers compared to non-caregivers was observed across income groups. Conclusions Our findings revealed a possible disparity in family caregivers under the public LTCI system. Further studies should examine factors associated with longer caregiving hours in lower income households. Our findings also suggest the necessity for more efforts to alleviate depressive symptoms in family caregivers under the LTCI system regardless of income level, rather than exclusively supporting those with a low income.

We sought to examine if self-reported oral health conditions regarding difficulty eating tough foods, dry mouth, choking, number of teeth and denture use are associated with incident falls. Our study was based on panel data from the Japan Gerontological Evaluation Study conducted in 2010 and 2013 using self-administered questionnaires. Data from 19,995 male and 20,858 female community-dwelling older people aged 65 years without a history of falls within the previous year in 2010 were analyzed. Multilevel logistic regression models were used to determine the association between poor oral health in 2010 and multiple incident falls in 2013 after adjusting for possible confounders and considering differences in municipalities. The percentage of males and females who reported falls in 2013 were 2.4% and 2.1%, respectively. After adjusting for age, educational attainment, equivalized income, depression, self-rated health, instrumental activities of daily living, body mass index, present illness related to falls, social participation, walking in min/day, alcohol drinking status, and municipality population density, dry mouth in males (odds ratio [OR] = 1.41 95% confidence interval [CI]: 1.12–1.77) and choking in females (OR = 1.64 95% CI: 1.27–2.11) were significantly associated with incident falls. Difficulty eating tough foods in both sexes and choking in males were marginally associated with incident falls (p&lt 0.1). Females having 10–19 teeth without dentures (OR = 1.63 95% CI: 1.14–2.31), 9 teeth with dentures (OR = 1.36 95% CI: 1.03–1.80), and 9 without dentures (OR = 1.46 95% CI: 1.02–2.08) were significantly associated with incident falls compared with those having 20 teeth, respectively. These findings suggest that poor oral function, having fewer teeth, and not using dentures are predictors of incident falls. Further studies are needed to determine whether improving oral health can reduce the risk of falls.

Background: A life-course perspective is essential in understanding the determinants of higher-level functional limitations. We examine the impact of adverse childhood experiences (ACEs) on higher-level functional limitations in older people. Methods: Data were from the Japan Gerontological Evaluation Study 2013, a population-based cohort of independent people aged 65 years or older across Japan (n = 19,220). ACEs before the age of 18 were assessed in terms of seven adversities: parental death, parental divorce, parental mental illness, family violence, physical abuse, psychological neglect, and psychological abuse. Associations between the cumulative number of ACEs and higher-level functional limitations were investigated by multivariate Poisson regression with robust error variances, adjusted for age, gender, childhood disadvantage, adult sociodemographics, adult health behaviors, and health status. Results: Of the older people, 36.3% reported at least one ACE. Older people who had experienced two or more ACEs showed significantly greater higher-level functional limitations than those with no ACE in a crude model (prevalence ratio, PR = 1.61, 95% confidence interval, CI = 1.51-1.71). After adjusting the covariates, this association remained (PR = 1.19, 95% CI = 1.12-1.27). Conclusions: ACEs showed robust independent effects on higher-level functional limitations among older Japanese without disabilities, even after adjusting for potential covariates in childhood and adulthood. The current findings may help in understanding the impact of the latent effects of ACEs on functional limitations in older people.

We examined correlating clinical biomarkers for the physical aspect of frailty among community-dwelling older adults in Japan, using Japanese Gerontological Evaluation Study (JAGES). We used information from the JAGES participants (N = 3,128) who also participated in the community health screening in 2010. We grouped participants' response to the Study of Osteoporotic Fracture (SOF) Frailty Index into robust (=0), intermediate frail (=1), and frail (=2+) ones to indicate physical aspect of frailty. Independent of sex and age, results from multinomial logistic regression showed above normal albumin and below normal HDL and haemoglobin levels were positively associated with intermediate frail (RRR = 1.99, 95% CI = 1.22-3.23 RRR = 1.36, 95% CI = 1.33-1.39 RRR = 1.36, 95% CI = 1.23-1.51, resp.) and frail cases (RRR = 2.27, 95% CI = 1.91-2.70 RRR = 1.59, 95% CI = 1.51-1.68 RRR = 1.40, 95% CI = 1.28-1.52, resp.). Limited to women, above normal Hb1Ac level was similarly associated with intermediate frail and frail cases (RRR = 1.18, 95% CI = 1.02, 1.38 RRR = 2.56, 95% CI = 2.23-2.95, resp.). Use of relevant clinical biomarkers can help in assessment of older adults' physical aspect of frailty.

Fruit and vegetable intake (FVI) contributes to the prevention of non-communicable diseases. Although food preference is considered to be determined early in life, few studies have investigated the association between childhood socioeconomic status (SES) and FVI in older age. Because a school lunch program was initiated in Japan after World War II, we were able in this study to examine this association in an older Japanese population. We used data from a population of physically and cognitively independent adults aged 65 years or older who were living independently in the community and were recruited from 27 municipalities in the Japan Gerontological Evaluation Study 2010 project (August 2010–January 2012). Three categories of childhood SES (low, middle, and high) and current FVI were evaluated via a self-reported questionnaire. Poisson regression was used to investigate the association between childhood SES and FVI in 19,920 individuals. After adjustment for age and sex, older people with low childhood SES were 1.36 times more likely (95% CI 1.23–1.52) to have poor FVI than those with high childhood SES. In the fully adjusted model, the significant association disappeared. Further age-stratified analysis revealed a positive association between childhood SES and FVI among people aged 70–76 years who were partially exposed to the school lunch program, but not among people aged 65–69 years old who were fully exposed to the program. In conclusion, social policy such as school lunches targeting children with low SES could help improve FVI in old age.

Background Social relationships consist of mutually related but distinct dimensions. It remains unclear how these domains independently contribute to incident dementia. This large-scale, prospective cohort study examines associations between the social relationship domains as well as their combinations and incident dementia among community-dwelling older adults. Methods We analysed data from 13 984 community-dwelling adults aged 65+ without long-term care needs living in Aichi prefecture in Japan. Incident dementia was assessed based on the Long-term Care Insurance records, followed for 3436 days from the baseline survey conducted in 2003. Three social relationships domains (social support, social networks and social activities) were further divided into a total of eight subdomains. A social relationship diversity score was calculated using the social relationship domains which were significantly related to incident dementia. Results A Cox proportional hazards model showed that being married, exchanging support with family members, having contact with friends, participating in community groups and engaging in paid work were related to a lower likelihood of developing incident dementia, controlling for covariates and other social relationship domains. The diversity scores, ranging from 0 to 5, were linearly associated with incident dementia (p<0.001), and those who scored highest were 46% less likely to develop incident dementia compared with those in the lowest category. Conclusions Our findings revealed five social relationship subdomains which were negatively related to incident dementia, suggesting that dementia may potentially be prevented by enhancing these social relationships. Future studies should examine independent pathways between each social relationship domain and incident dementia.

BACKGROUND: A rapidly ageing population presents major challenges to health and social care services. Cross-country comparative studies on survival among older adults are limited. In addition, Japan, the country with the longest life expectancy, is rarely included in these cross-country comparisons. OBJECTIVE: We examined the relative contributions of social and behavioural factors on the differences in survival among older people in Japan and England. METHODS: We used data from the Japan Gerontological Evaluation Study (JAGES; n = 13,176) and the English Longitudinal Study of Ageing (ELSA; n = 5,551) to analyse all-cause mortality up to 9.4 years from the baseline. Applying Laplace regression models, the 15th survival percentile difference was estimated. RESULTS: During the follow-up, 31.3% of women and 38.6% of men in the ELSA died, whereas 19.3% of women and 31.3% of men in the JAGES died. After adjusting for age and baseline health status, JAGES participants had longer survival than ELSA participants by 318.8 days for women and by 131.6 days for men. Family-based social relationships contributed to 105.4 days longer survival in JAGES than ELSA men. Fewer friendship-based social relationships shortened the JAGES men's survival by 45.4 days compared to ELSA men. Currently not being a smoker contributed to longer survival for JAGES women (197.7 days) and ELSA men (46.6 days), and having lower BMI reduced the survival of JAGES participants by 129.0 days for women and by 212.2 days for men. CONCLUSION: Compared to participants in England, Japanese older people lived longer mainly because of non-smoking for women and family-based social relationships for men. In contrast, a lower rate of underweight, men's better friendship-based social relationships, and a lower smoking rate contributed to survival among participants in England.

Objectives Influenza infection can cause severe pneumonia, which is sometimes fatal, particularly in older adults. Influenza results in 3-5 million cases of severe illness and about 250 000 to 500 000 deaths annually worldwide. Social participation in the context of influenza infection is controversial because, although social participation is beneficial in maintaining physical function and mental health, it also increases the risk of contact with infected people. This study examined the association between social participation and influenza infection in Japanese adults aged 65 years or older.Design Cross-sectional study.Setting Japanese functionally independent adults aged 65 years or older.Participants Among the respondents to the Japan Gerontological Evaluation Study (JAGES) 2013 survey, which took place during the period from October to December 2013, 12 231 men and 14 091 women responded to questions on influenza vaccination and influenza infection.Outcome measures Using JAGES data for 12 231 men and 14 091 women aged >= 65 years, we examined the association between social participation and influenza infection. The association between influenza infection and number of groups in which respondents participated was investigated among adults aged >= 65 years, stratified by vaccination status and sex.Results Unvaccinated women who participated in two or more social activities were 2.20 times (95% CI 1.47 to 3.29) as likely to report an influenza infection as those who reported no social participation. In contrast, vaccinated women who participated in two or more social groups had no additional risk of influenza infection as compared with female elders with no social participation. Among men, participation in social activities was riot significantly associated with influenza infection, regardless of vaccination status.Conclusions Social participation was associated with a higher risk of influenza infection among unvaccinated older women, which suggests a need for further efforts to promote influenza vaccination, particularly among socially active elderly women.

BACKGROUND: Several previous studies reported social participation may reduce the incident of dementia; therefore, the type of positions held in the organization may relate to dementia onset. However, this hypothesis remains largely unknown. The purpose of the present study was to examine the additive effect of a leadership position in the organization on dementia onset and social participation among elderly people in a local community, according to data from a Japanese older adults cohort study. METHODS: Of 29,374 community-dwelling elderly, a total of 15,313 subjects responded to the baseline survey and were followed-up from November 2003 to March 2013. To evaluate the association between dementia onset and social participation as well as the role in the organization, we conducted Cox proportional hazard regression analysis with multiple imputation by age group (aged 75 years older or younger). The dependent variable was dementia onset, which was obtained from long-term care insurance data in Japan; independent variables were social participation and the role in the organization to which they belonged (head, manager, or treasurer). Covariates were sex, age, educational level, marriage status, job status, residence status, alcohol consumption, smoking status, and walking time, instrumental activities of daily living, depression, and medical history. RESULTS: During the follow-up period, 708 young-old elderly people (7.7%) and 1289 old-old elderly people (27.9%) developed dementia. In young-old elderly, relative to social non-participants, adjusted Hazard Ratio (HR) for dementia onset for participants (regular members + leadership positions) was 0.75 (95% confidence interval (CI), 0.64-0.88). Relative to regular members, adjusted HR for dementia onset for non-participants was 1.22 (95% CI, 1.02-1.46), for leadership positions 0.81 (95% CI, 0.65-0.99). The results for old-old elderly participants did not show that any significantly adjusted HR between dementia onset and social participation, the role in the organization. CONCLUSIONS: In young-old elderly people, social participation might have a positive effect on dementia onset, and holding leadership positions in organization could lead to a decrease in risk of dementia onset by almost 20% than regular members.

Background: Food access is important for maintaining dietary variety, which predicts underweight. The aim of this study was to examine the association of food access and neighbor relationships with eating and underweight. Methods: We analyzed cross-sectional data from 102,869 Japanese individuals aged 65 years or older. The perceived availability of food was assessed using the presence or absence of food stores within 1 km of the home. Level of relationships with neighbors was also assessed. The odds ratios (ORs) and 95% confidence intervals (CIs) for infrequent food intake and underweight were determined using logistic regression analysis. Results: The proportion of men and women having low access to food was 25-30%. Having low food access (OR 1.18; 95% CI, 1.12-1.25 for men and OR 1.26; 95% CI, 1.19-1.33 for women) and a low level of relationship with neighbors (OR 1.38; 95% CI, 1.31-1.45 for men and OR 1.57; 95% CI, 1.48e1.67 for women) was associated with infrequent intake of fruits and vegetables in both sexes. Association between low food access and infrequent intake of fruits and vegetables was higher among men with low levels of neighbor relationship (OR 1.34; 95% CI, 1.23-1.46) than among men with high levels of relationship (OR 1.10; 95% CI, 1.03-1.18). Conclusions: Low perceived availability of food is a risk factor for low dietary variety among older people. Furthermore, high levels of relationship with neighbors may relieve the harmful effect of low food access. (C) 2017 The Authors. Publishing services by Elsevier B. V. on behalf of The Japan Epidemiological Association.

The Japan Gerontological Evaluation Study is a nationwide cohort study of individuals aged 65 years and older established in July 2010. Seven months later, one of the study field sites was directly in the line of the 2011 Great East Japan Earthquake and Tsunami. Despite the 1-hour warning interval between the earthquake and tsunami, many coastal residents lost their lives. We analyzed the risk of all-cause mortality on the day of the disaster as well as in the 38-month interval after the disaster. Among 860 participants, 33 (3.8%) died directly because of the tsunami and an additional 95 people died during the 38-month follow-up period. Individuals with depressive symptoms had elevated risk of mortality on the day of the disaster (odds ratio = 3.90 [95% CI: 1.13, 13.47]). More socially connected people also suffered increased risk of mortality, although these estimates were not statistically significant. In contrast, after the disaster, frequent social interactions reverted back to predicting improved survival (hazard ratio = 0.46 (95% CI: 0.26, 0.82)). Depressive symptoms and stronger social connectedness were associated with increased risk of mortality on the day of the disaster. After the disaster, social interactions were linked to improved survival.

ObjectiveTo study the association between the number of area-level and individual-level social participation items and cognitive function in the community-dwelling older populations of three towns in Hokkaido, Japan. MethodsA survey on the frequency of social participation was mailed to those in the Japan Gerontological Evaluation Study 2013 who were aged 65years, were not certified as needing long-term care, and lived in Higashikawa, Higashikagura, or Biei. A subset of participants aged 70-74years completed the Japanese version of the Montreal Cognitive Assessment in a home visit survey. Both the area-level and individual-level social participation and demographic information were obtained on the self-administered questionnaire. A multilevel analysis using a generalized linear mixed-effects model was used to examine the association between variables in the area-level and individual-level social participation items and cognitive function. ResultsOut of 4042 respondents, data from 2576 were used in the area-level analysis. Of those, 180 were aged 70-74years and completed the home visit survey for the individual-level analysis. A greater number of higher social participation items at the individual level was associated with higher cognitive function scores after adjusting for area-level social participation variables and confounders (regression coefficient: 0.19; 95% confidence interval: 0.03, 0.35). There were no significant associations between area-level social participation item averages and individual-level cognitive function scores. ConclusionsOlder populations participating in many kinds of social activities exhibited preserved cognitive function even after adjusting for area-level social participation variables. Copyright (c) 2016 John Wiley & Sons, Ltd.

Introduction: Income is hypothesized to affect health not just through material pathways (i.e., the ability to purchase health-enhancing goods) but also through psychosocial pathways (e.g., social comparisons with others). Two concepts relevant to the psychosocial effects of income are: relative deprivation (for example expressed by the Yitzhaki Index, measuring the magnitude of difference in income among individuals) and Income Rank. This study examined whether higher relative deprivation and lower income rank are associated with depressive symptoms in an older population independently of absolute income. Method: Using cross-sectional data of 83,100 participants (40,038 men and 43,062 women) in the Japan Gerontological Evaluation Study (JAGES), this study applied multiple logistic regression models to calculate the odds ratios (OR) of depression associated with relative deprivation/Income Rank. The Japanese Geriatric Depression Scale (GDS-15) was used to assess depressive symptoms, and subjects with a score of >5 were categorized as depressed. Reference groups for calculating the Yitzhaki Index and income rank were constructed based on same gender, age-group, and municipality of residence. Results: The findings indicated that after controlling for demographic factors, each 100,000 yen increase in relative deprivation and 0.1 unit decrease in relative rank was associated with a 1.07 (95% CI = 1.07, 1.08) and a 1.15 (95% CI = 1.14, 1.16) times higher odds of depression, respectively, in men. The corresponding ORs in women were 1.05 (95% CI = 1.05, 1.06) and 1.12 (95% CI = 1.11, 1.13), respectively. After adjustment for other covariates and stratification by income quartiles, the results remained statistically significant. Women in the highest income quartile appeared to be more susceptible to the adverse mental health effects of low income rank, while among men the associations were reversed. Low income rank appeared to be more toxic for the poor. Conclusion: Concepts of relative income appear to be relevant for mental health over and above the effects of absolute income. (C) 2017 Elsevier Ltd. All rights reserved.

健康の社会的決定要因が呼吸器疾患の主要促進要因の1つであることが明らかになってきている。米国・欧州両呼吸器学会によると、低所得、低教育歴、不健康な職業など、社会経済的に不利な集団は有利な集団に比べて呼吸器疾患リスクが約14倍も高くなる。日本人を対象にした分析でも、特に男性において教育歴で1.6倍の健康格差が認められる。また、呼吸器疾患の発症や死亡率に関連する健康格差に関わるリスクファクターの代表格として喫煙が挙げられる。本稿では、日本人においても呼吸器疾患での死亡率を2倍にすることが明らかとなっている喫煙を例として、健康格差のメカニズムに迫り、その対策について考えていく。(著者抄録)

This study examined whether the number of teeth contributes to the compression of morbidity, measured as a shortening of life expectancy with disability, an extension of healthy life expectancy, and overall life expectancy. A prospective cohort study was conducted. A self-reported baseline survey was given to 126,438 community-dwelling older people aged >= 65 y in Japan in 2010, and 85,161 (67.4%) responded. The onset of functional disability and all-cause mortality were followed up for 1,374 d (follow-up rate = 96.1%). A sexstratified illness-death model was applied to estimate the adjusted hazard ratios (HRs) for 3 health transitions (healthy to dead, healthy to disabled, and disabled to dead). Absolute differences in life expectancy, healthy life expectancy, and life expectancy with disability according to the number of teeth were also estimated. Age, denture use, socioeconomic status, health status, and health behavior were adjusted. Compared with the edentulous participants, participants with = 20 teeth had lower risks of transitioning from healthy to dead (adjusted HR, 0.58 [95% confidence interval (CI), 0.50-0.68] for men and 0.70 [95% CI, 0.57-0.85] for women) and from healthy to disabled (adjusted HR, 0.52 [95% CI, 0.44-0.61] for men and 0.58 [95% CI, 0.49-0.68] for women). They also transitioned from disabled to dead earlier (adjusted HR, 1.26 [95% CI, 0.99-1.60] for men and 2.42 [95% CI, 1.72-3.38] for women). Among the participants aged = 85 y, those with = 20 teeth had a longer life expectancy (men: +57 d; women: +15 d) and healthy life expectancy (men: +92 d; women: +70 d) and a shorter life expectancy with disability (men: -35 d; women: -55 d) compared with the edentulous participants. Similar associations were observed among the younger participants and those with 1 to 9 or 10 to 19 teeth. The presence of remaining teeth was associated with a significant compression of morbidity: older Japanese adults' life expectancy with disability was compressed by 35 to 55 d within the follow-up of 1,374 d.

Background: Living arrangements of older adults have changed worldwide with increasing solitary and non-spouse households, which could affect social care systems. However, the relationship between these households and disability onset has remained unclear. We examined the relationship between living arrangements and the onset of basic activities of daily living disability in older adults, with a focus on gender differences and cohabitation status of those without a spouse. Methods: Data from 6600 men and 6868 women aged 65 years or older without disability were obtained from the Aichi Gerontological Evaluation Study Project in Japan. Onset of disability was followed for 9.4 years. Disability was assessed based on Long-term Care Insurance System registration. A hierarchical Cox proportional hazards model was conducted to examine the risk of living alone and living only with non-spousal cohabitants compared to those living with spouses. Results: Men living only with non-spousal cohabitants and those living alone were significantly more likely to develop disability after controlling for health and other covariates (hazard ratio = 1.38 and 1.45, respectively), while a significant difference was found only for women living alone (hazard ratio = 1.19). The risk of living with non-spousal cohabitants was marginally stronger in men, indicated by the interaction effect model (p = .08). A series of hierarchical analyses showed that social support exchange explained 24.4% and 15.8% of the excess risk of disability onset in men living alone and those living only with non-spousal cohabitants, respectively. A subsequent analysis also showed that support provision by older adults more greatly explained such excess risk than receiving support from others. Conclusions: Older men without spouses were more likely to develop disability onset regardless of cohabitants. Health professionals should consider programs that enhance social support exchange, particularly support provision by older adults who are at risk of disability.

In Asian nations, family ties are considered important. However, it is not clear what happens among older people with no such ties. To investigate the association, we used longitudinal data from the Aichi Gerontological Evaluation Study (AGES) project. Functionally independent older people at baseline (N = 14,088) in 10 municipalities were followed from 2003 to 2013. Social ties were assessed by asking about their social support exchange with family, relatives, friends, or neighbors. Cox proportional hazard models were employed to investigate the association between social ties and the onset of functional disability adjusting for age, health status, and living arrangement. We found that social ties with co-residing family members, and those with friends or neighbors, independently protected functional health with hazard ratios of 0.81 and 0.85 among men. Among women, ties with friend or neighbors had a stronger effect on health compared to their male counterparts with a hazard ratio of 0.89. The fact that social ties with friends or neighbors are associated with a lower risk of functional decline, independent of family support, serves to underscore the importance of promoting social ties, especially among those lacking family ties.

In Asian nations, family ties are considered important. However, it is not clear what happens among older people with no such ties. To investigate the association, we used longitudinal data from the Aichi Gerontological Evaluation Study (AGES) project. Functionally independent older people at baseline (N = 14,088) in 10 municipalities were followed from 2003 to 2013. Social ties were assessed by asking about their social support exchange with family, relatives, friends, or neighbors. Cox proportional hazard models were employed to investigate the association between social ties and the onset of functional disability adjusting for age, health status, and living arrangement. We found that social ties with co-residing family members, and those with friends or neighbors, independently protected functional health with hazard ratios of 0.81 and 0.85 among men. Among women, ties with friend or neighbors had a stronger effect on health compared to their male counterparts with a hazard ratio of 0.89. The fact that social ties with friends or neighbors are associated with a lower risk of functional decline, independent of family support, serves to underscore the importance of promoting social ties, especially among those lacking family ties.

Social connections in the community ("social capital") represent an important source of resilience in the aftermath of major disasters. However, little is known about how residential relocation due to housing destruction affects survivors' social capital. We examined changes in social capital among survivors of the 2011 Great East Japan Earthquake and Tsunami. People who lost their homes were resettled to new locations by two primary means: (i) group relocation to public temporary trailer housing or (ii) individual relocation, in which victimsmoved into government-provided housing by lottery or arranged for theirown accommodation (market rental housing or private purchase/new construction). The baseline for our natural experiment was established 7 months before the 11 March 2011 disaster, when we conducted a survey of older community-dwelling adultswho lived 80-km west of the earthquake epicenter. Approximately 2.5 years after the disaster, the follow-up survey gathered information about personal experiences of disaster as well as health status and social capital. Among 3421 people in our study, 79 people moved via group relocation to public temporary trailer housing, whereas 96 people moved on their own. The individual fixed-effects model showed that group relocationwas associated with improved informal socializing and social participation (beta coefficient = 0.053, 95% confidence interval: 0.011 to 0.095). In contrast, individual relocationwas associated with declining informal socializing and social participation (beta coefficient = -0.039, 95% confidence interval: -0.074 to -0.003). Group relocation, as compared to individual relocation, appeared to preserve social participation and informal socializing in the community.

Oral health status is correlated with socioeconomic status. However, the causal nature of the relationship is not established. Here we describe a natural experiment involving deteriorating socioeconomic circumstances following exposure to the 2011 Great East Japan Earthquake and Tsunami. We investigated the relationship between subjective economic deterioration and housing damage due to the disaster and tooth loss in a cohort of community-dwelling residents (n = 3,039), from whom we obtained information about socioeconomic status and health status in 2010 (i.e., predating the disaster). A follow-up survey was performed in 2013 (postdisaster), and 82.1% of the 4,380 eligible survivors responded. We estimated the impact of subjective economic deterioration and housing damage due to the disaster on tooth loss by fitting an instrumental variable probit model. Subjective economic deterioration and housing damage due to the disaster were significantly associated with 8.1% and 1.7% increases in the probability of tooth loss (probit coefficients were 0.469 (95% confidence interval: 0.065, 0.872) and 0.103 (95% confidence interval: 0.011, 0.196), respectively). In this natural experiment, we confirmed the causal relationship between deteriorating socioeconomic circumstances and tooth loss.

BACKGROUND: Although living in a hilly environment may promote muscular activity in the daily lives of residents, and such activity may prevent diabetes mellitus, few studies have focused on the impact of living in a hilly environment on diabetes mellitus. The purpose of this study was to investigate the impact of a hilly neighborhood environment on DM in older people. METHODS: We used data from the Japan Gerontological Evaluation Study, a population-based, cross-sectional study of individuals aged 65 or older without long-term care needs in Japan, which was conducted in 2010. A total of 8904 participants in 46 neighborhoods had responded to the questionnaire and undergone a health check. Diabetes mellitus was diagnosed as HbA1c ≥ 6.5% and those undergoing treatment for diabetes mellitus. Poorly controlled diabetes mellitus was diagnosed in those without other chronic diseases who had an HbA1c > 7.5%, and in those with other chronic diseases if their HbA1c was >8.0%. Neighborhood environment was evaluated based on the percentage of positive responses in the questionnaire and geographical information system data. A multilevel analysis was performed, adjusted for individual-level risk factors. Furthermore, sensitivity analysis was conducted for those who were undergoing treatment for diabetes mellitus (n = 1007). RESULTS: After adjustment for other physical environmental and individual covariates, a 1 interquartile range increase (1.48°) in slope in the neighborhood decreased the risk of poorly controlled diabetes mellitus by 18% (odds ratio [OR]: 0.82, 95% confidence interval [CI]: 0.70-0.97). Sensitivity analysis confirmed that larger slopes in the neighborhood showed a significant protective effect against diabetes mellitus among those who were undergoing treatment for diabetes mellitus (OR: 0.73, 95% CI: 0.59-0.90). CONCLUSION: A hilly neighborhood environment was not associated with diabetes mellitus, but was protective against poorly controlled diabetes mellitus.

Background: We examined prospectively whether social capital mitigates the adverse effects of natural disaster on cognitive decline. Methods: The baseline for our study was established seven months before the 2011 Great East Japan Earthquake and Tsunami in a survey of older community-dwelling adults who lived 80 kilometers west of the epicenter (59.0% response rate). Approximately two and a half years after the disaster, the follow-up survey gathered information about personal experiences of disaster as well as incidence of cognitive disability (82.1% follow-up rate). Our primary outcome was cognitive disability (measured on an 8-level scale) assessed by in-home assessment. Findings: The experience of housing damage was associated with risk of cognitive impairment (coefficient = 0.04, 95% confidence interval: 0.02 to 0.06). Factor analysis of our analytic sample (n = 3,566) established two sub-scales of social capital: a cognitive dimension (perceptions of community social cohesion) and a structural dimension (informal socializing and social participation). Fixed effects regression showed that informal socializing and social participation buffered the risk of cognitive decline resulting from housing damage. Interpretation: Informal socializing and social participation may prevent cognitive impairment following natural disaster. Funding: National Institutes of Health (R01AG042463-04), the Japan Society for the Promotion of Science, the Japanese Ministry of Health, Labour and Welfare and the Japanese Ministry of Education, Culture, Sports, Science and Technology.

Background: Although living in a hilly environment may promote muscular activity in the daily lives of residents, and such activity may prevent diabetes mellitus, few studies have focused on the impact of living in a hilly environment on diabetes mellitus. The purpose of this study was to investigate the impact of a hilly neighborhood environment on DM in older people.Methods: We used data from the Japan Gerontological Evaluation Study, a population-based, cross-sectional study of individuals aged 65 or older without long-term care needs in Japan, which was conducted in 2010. A total of 8904 participants in 46 neighborhoods had responded to the questionnaire and undergone a health check. Diabetes mellitus was diagnosed as HbA(1c) >= 6.5% and those undergoing treatment for diabetes mellitus. Poorly controlled diabetes mellitus was diagnosed in those without other chronic diseases who had an HbA(1c) > 7.5%, and in those with other chronic diseases if their HbA(1c) was > 8.0%. Neighborhood environment was evaluated based on the percentage of positive responses in the questionnaire and geographical information system data. A multilevel analysis was performed, adjusted for individual-level risk factors. Furthermore, sensitivity analysis was conducted for those who were undergoing treatment for diabetes mellitus (n = 1007).Results: After adjustment for other physical environmental and individual covariates, a 1 interquartile range increase (1.48 degrees) in slope in the neighborhood decreased the risk of poorly controlled diabetes mellitus by 18% (odds ratio [OR]: 0.82, 95% confidence interval [CI]: 0.70-0.97). Sensitivity analysis confirmed that larger slopes in the neighborhood showed a significant protective effect against diabetes mellitus among those who were undergoing treatment for diabetes mellitus (OR: 0.73, 95% CI: 0.59-0.90).Conclusion: A hilly neighborhood environment was not associated with diabetes mellitus, but was protective against poorly controlled diabetes mellitus. (C) 2017 Elsevier Ltd. All rights reserved.

Background: Empirical evidence investigating heterogeneous impact of retirement on mental health depending on social backgrounds is lacking, especially among older adults. Methods: We examined the impact of changes in working status on changes in mental health using Japanese community-dwelling adults aged >= 65 years participating in the Japan Gerontological Evaluation Study between 2010 and 2013 (N = 62,438). Between-waves changes in working status ("Kept working", "Retired", "Started work", or "Continuously retired") were used to predict changes in depressive symptoms measured by the Geriatric Depression Scale. First-difference regression models were stratified by gender, controlling for changes in time-varying confounding actors including equivalised household income, marital status, instrumental activities of daily living, incidence of serious illnesses and family caregiving. We then examined the interactions between changes in working status and occupational class, changes in marital status, and post-retirement social participation. Results: Participants who transitioned to retirement reported significantly increased depressive symptoms (beta = 0.33, 95% CI: 0.21-0.45 for men, and beta = 0.29, 95% CI: 0.13-0.45 for women) compared to those who kept working. Men who were continuously retired reported increased depressive symptoms (beta = 0.13, 95% CI: 0.05-0.20), whereas males who started work reported decreased depressive symptoms (beta = -0.20, 95% CI: -0.38-0.02). Men from lower occupational class (compared to men from higher class) reported more increase in depressive symptoms when continuously retired (beta = -0.16, 95% CI: -0.25-0.08). Those reporting recreational social participation after retirement appeared to be less influenced by transition to retirement. Conclusions: Retirement may increase depressive symptoms among Japanese older adults, particularly men from lower occupational class backgrounds. Encouraging recreational social participation may mitigate the adverse effects of retirement on mental health of Japanese older men.

ObjectivesTo determine whether oral health status predicts depressive symptoms in older Japanese people. DesignLongitudinal study. SettingTwenty-four municipalities in Japan. ParticipantsCommunity-dwelling individuals aged 65 years and older who responded to mail surveys performed by the Japan Gerontological Evaluation Study in 2010 and 2013 (N = 14,279). MeasurementsDepressive symptoms were assessed using the Geriatric Depression Scale (GDS). Multiple imputations were used to deal with missing data. After excluding participants with depressive symptoms (GDS 5) at baseline, odds ratios (ORs) and 95% confidence intervals (CIs) for incident depressive symptoms in 2013 were estimated using logistic regression models. ResultsAfter adjusting for sex, age, educational attainment, equivalized household income, marital status, present illness, exercise, frequency of going out, and visits for dental treatment, the following ORs (95% CIs) were observed in simultaneously added oral health variables: 10-19 teeth (OR 1.16, 95% CI 0.99-1.37, reference: 20 teeth); 1-9 teeth (1.14, 0.94-1.38, reference: 20 teeth); no teeth (1.28, 1.03-1.60, reference: 20 teeth); more difficulty chewing tough foods now than 6 months ago (1.24, 1.04-1.47); choking when drinking tea or soup (1.02, 0.84-1.23); feelings of thirst (1.17, 0.99-1.40); difficulty eating food (0.98, 0.80-1.21), difficulty speaking clearly (1.19, 0.89-1.60); problems with smiling (1.24, 0.94-1.65); problems with emotional stability (1.32, 0.86-2.04); and problems enjoying oneself around family, friends, or other people (0.86, 0.42-1.78). ConclusionThese findings suggest that having no teeth and oral health problems may play a role in the development or worsening of depressive symptoms.

Background: We developed and validated an instrument to measure community-level social capital based on data derived from older community dwellers in Japan. Methods: We used cross-sectional data from the Japan Gerontological Evaluation Study, a nationwide survey involving 123,760 functionally independent older people nested within 702 communities (i.e., school districts). We conducted exploratory and confirmatory factor analyses on survey items to determine the items in a multi-dimensional scale to measure community social capital. Internal consistency was checked with Cronbach's alpha. Convergent construct validity was assessed via correlating the scale with health outcomes. Results: From 53 candidate variables, 11 community-level variables were extracted: participation in volunteer groups, sports groups, hobby activities, study or cultural groups, and activities for teaching specific skills; trust, norms of reciprocity, and attachment to one's community; received emotional support; provided emotional support; and received instrumental support. Using factor analysis, these variables were determined to belong to three sub-scales: civic participation (eigenvalue = 3.317, alpha = 0.797), social cohesion (eigenvalue = 2.633, alpha = 0.853), and reciprocity (eigenvalue = 1.424, alpha = 0.732). Confirmatory factor analysis indicated the goodness of fit of this model. Multilevel Poisson regression analysis revealed that civic participation score was robustly associated with individual subjective health (Self-Rated Health: prevalence ratio [PR] 0.96; 95% confidence interval [CI], 0.94-0.98; Geriatric Depression Scale [GDS]: PR 0.95; 95% CI, 0.93-0.97). Reciprocity score was also associated with individual GDS (PR 0.98; 95% CI, 0.96-1.00). Social cohesion score was not consistently associated with individual health indicators. Conclusions: Our scale for measuring social capital at the community level might be useful for future studies of older community dwellers. (C) 2016 The Authors. Publishing services by Elsevier B.V. on behalf of The Japan Epidemiological Association.

Objective: To investigate whether self-exercise programs for patients after stroke contribute to improved activities of daily living (ADL) at hospital discharge. Design: Retrospective, observational, propensity score (PS) matched case-control study. Setting: General hospitals. Participants: Participants included patients after stroke (N=1560) hospitalized between January 3, 2006, and December 26, 2012, satisfying the following criteria: (1) data on age, sex, duration from stroke to hospital admission, length of stay, FIM score, modified Rankin Scale (mRS) score, Glasgow Coma Scale score, Japan Stroke Scale score, and self-exercise program participation were available; and (2) admitted within 7 days after stroke onset, length of stay was between 7 and 60 days, prestroke mRS score was < 2, and not discharged because of FEW or mRS exacerbation. A total of 780 PS-matched pairs were selected for each of the self-exercise program and no self-exercise program groups. Intervention: Self-exercise program participation. Main Outcome Measures: At discharge, FIM motor score, FIM cognitive score, FIM motor score gain (discharge value admission value), FIM motor score gain rate (gain/length of stay), a binary variable divided by the median FIM motor score gain rate (high efficiency or no high efficiency), and mRS score. Results: Patients were classified into a self-exercise program (n=780) or a no self-exercise program (n =780) group. After matching, there were no significant between-group differences, except motor system variables. The receiver operating characteristic curve for PS had an area under the curve value of .71 with a 95% confidence interval of .68 to .73, and the model was believed to have a relatively favorable fit. A logistic regression analysis of PS-matched pairs suggested that the self-exercise program was effective, with an overall odds ratio for ADL (high efficiency or no high efficiency) of 2.2 (95% confidence ratio, 1.75-2.70). Conclusions: SEPs may contribute to improving ADL. (C) 2016 by the American Congress of Rehabilitation Medicine

Introduction: We described associations between the type of disaster experience and change in instrumental activities of daily living among older adult survivors before-after a terrible disaster. Methods: The study took advantage of a "natural experiment" afforded by the Japan Gerontological Evaluation Study (JAGES), a nationwide cohort study established in 2010, seven months prior to the earthquake and tsunami. A follow-up survey was conducted in 2013. This study was conducted in Iwanuma, which was directly struck by tsunami. Our sample comprised community-dwelling aged survivors in Iwanuma who responded to questions about personal circumstances and functional status both before and after the disaster (N = 3547). Personal experiences of earthquake and tsunami damage was used as an exposure variable. The outcome was changes in self-reported 13-item instrumental activities of daily living (IADL), which was assessed both before and after the disaster. Results: Among the participants, 931 reported losing family member(s) to the disaster, while a further 549 reported losing friend(s). More than half of the participants reported any damage to their houses while approximately 1 in 8 lost their car(s). The multivariable OLS regression revealed that complete house loss and disruption of internal medicine were associated with significantly worse IADL: -0.67 points (95%CI: -0.99, -0.34) for entirely destroyed homes; -0.40 points (95% CI: -0.71, -0.092) for disruption of internal medicine. By contrast, loss of family/friends/pets/cars and disruption to the other medical service were not associated with decline in IADL. Conclusion: Complete house loss and disruption of access to internal medicine after a disaster were associated with significant adverse impact on decline in physical and cognitive functions 2.5 years after the disaster, while loss of family/friends was not. (C) 2017 Elsevier Ltd. All rights reserved.

Objectives: Survivors of the 2011 Great East Japan Earthquake have an increased risk of depressive symptoms. We sought to examine whether participation in group exercise and regular walking could mitigate the worsening of depressive symptoms among older survivors. Design: Prospective observational study. Setting: Our baseline survey was conducted in August 2010, similar to 7 months prior to the Great East Japan Earthquake and tsunami, among people aged 65 or older residing in Iwanuma City, Japan, which suffered significant damage in the disaster. A 3- year follow- up survey was conducted in 2013. Participants: 3567 older survivors responded to the questionnaires predisaster and postdisaster. Primary outcome measures: Change in depressive symptoms was assessed using the 15- item Geriatric Depression Scale (GDS). Results: From predisaster to postdisaster, the mean change in GDS score increased by 0.1 point (95% CI -0.003 to 0.207). During the same interval, the frequency of group exercise participation and daily walking time also increased by 1.9 days/ year and 1.3 min/ day, respectively. After adjusting for all covariates, including personal experiences of disaster, we found that increases in the frequency of group exercise participation (B=-0.139, beta=-0.049, p=0.003) and daily walking time (B=- 0.087, beta=-0.034, p= 0.054) were associated with lower GDS scores. Interactions between housing damage and changes in group exercise participation (B=0.103, beta=0.034, p=0.063) and changes in walking habit (B=0.095, beta=0.033, p=0.070) were marginally significant, meaning that the protective effects tended to be attenuated among survivors reporting more extensive housing damage. Conclusions: Participation in group exercises or regular walking may mitigate the worsening of depressive symptoms among older survivors who have experienced natural disaster.

Introduction There are few intervention studies that demonstrated linking social participation to lower risk of cognitive decline. We examined prospectively the protective effect of a community intervention program promoting social participation on the incidence of cognitive disability. Methods The baseline was established in a survey of community-dwelling older people aged 65 years old or more in July 2006 (2793 respondents, response rate 48.5%). The setting was Taketoyo town in Japan, where municipal authorities launched an intervention that was based on the establishment of community-based centers called “salons,” where the town's senior residents could congregate and participate in social activities, ranging from arts and crafts, games, and interactive activities with preschool children. Three salons were established in May 2010, and a total of 10 salons were in operation by 2013. We recorded the frequency of salon participation among survey respondents till 2013 and conducted two follow-up surveys (in 2010 and 2013) to collect information about health status and behaviors. The onset of cognitive disability was followed from May 2007 to January 2014. We used the marginal structural models to evaluate the effect of program. Results The range of prevalence of cognitive disability was from 0.2% to 2.5% during the observation period. The proportion of respondents who participates to salons increased over time to about 11.7%. The frequency of salon participation was protectively associated with cognitive decline, even after adjusting for time-dependent covariates and attrition (odds ratio = 0.73, 95% confidence interval: 0.54–0.99). Discussion Our study suggests that operating community salons that encourage social interactions, light physical activity, and cognitive activities among older participants may be effective for preventing cognitive decline. In future studies, we need to understand what sorts of activities (e.g., those involving light physical activity vs. purely intellectual activities) are most effective in maintaining cognitive function.

Aim The present study examined whether social support, informal socializing and social participation are associated with glycemic control in older people. Methods Data for this population-based cross-sectional study was obtained from the Japan Gerontological Evaluation Study (JAGES) 2010 linked to the annual health check-up data in Japan. We analyzed 9,554 individuals aged >= 65 years without the certification of needed long-term care. Multivariate logistic regression models were used to assess the effect of social support, informal socializing and social participations on glycemic control. The outcome measure was HbA1c >= 8.4%. Results 1.3% of the participants had a level of HbA1c over 8.4%. Better glycemic control was significantly associated with meeting with friends one to four times per month (odds ratio [OR] 0.51, 95% confidence interval [CI] 0.30-0.89, compared to meeting with friends a few times per year or less) and participation in sports groups (OR 0.50, 95% CI 0.26-0.97) even after adjusting for other variables. Meeting with friends more than twice per week, receiving social support, and being married were not associated with better control of diabetes. Conclusions Meeting with friends occasionally is associated with better glycemic control among older people.

Background: We examined the associations of informal (eg, family members and friends) and formal (eg, physician and visiting nurses) social support with caregiver's burden in long-term care and the relationship between the number of available sources of social support and caregiver burden. Methods: We conducted a mail-in survey in 2003 and used data of 2998 main caregivers of frail older adults in Aichi, Japan. We used a validated scale to assess caregiver burden. Results: Multiple linear regression demonstrated that, after controlling for caregivers' sociodemographic and other characteristics, informal social support was significantly associated with lower caregiver burden (beta = -1.59, P < 0.0001), while formal support was not (beta = -0.30, P = 0.39). Evaluating the associations by specific sources of social support, informal social supports from the caregiver's family living together (beta = -0.71, P < 0.0001) and from relatives (beta = -0.61, P = 0.001) were associated with lower caregiver burden, whereas formal social support was associated with lower caregiver burden only if it was from family physicians (beta = -0.56, P = 0.001). Compared to caregivers without informal support, those who had one support (beta = -1.62, P < 0.0001) and two or more supports (beta = -1.55, P < 0.0001) had significantly lower burden. This association was not observed for formal support. Conclusions: Social support from intimate social relationships may positively affect caregivers' psychological wellbeing independent of the receipt of formal social support, resulting in less burden.

ObjectivesFrom a life-course perspective, adverse childhood experiences (ACEs) such as childhood abuse are known risk factors for adult diseases and death throughout life. ACEs could also cause poor dental health in later life because they could induce poor dental health in childhood, initiate unhealthy behaviors, and lower immune and physiological functions. However, it is not known whether ACEs have a longitudinal adverse effect on dental health in older age. This study aimed to investigate the association between experience of childhood abuse until the age of 18 and current number of remaining teeth among a sample of older Japanese adults. MethodsA retrospective cohort study was conducted using the data from the Japan Gerontological Evaluation Study (JAGES), a large-scale, self-reported survey in 2013 including 27 525 community-dwelling Japanese aged 65 years (response rate=71.1%). The outcome, current number of remaining teeth was used categorically: 20, 10-19, 5-9, 1-4, and no teeth. Childhood abuse was defined as having any experience of physical abuse, psychological abuse, and psychological neglect up until the age of 18 years. Ordered logistic regression models were applied. ResultsOf the 25 189 respondents who indicated their number of remaining teeth (mean age: 73.9; male: 46.5%), 14.8% had experience of childhood abuse. Distributions of 20, 10-19, 5-9, 1-4, and no teeth were as follows: 46.6%, 22.0%, 11.4%, 8.2%, and 11.8% among respondents with childhood abuse, while 52.3%, 21.3%, 10.3%, 6.6%, and 9.5% among respondents without childhood abuse. Childhood abuse was significantly associated with fewer remaining teeth after adjusting for covariates including socioeconomic status (odds ratio=1.14; 95% confidence interval: 1.06, 1.22). ConclusionsChildhood abuse could have a longitudinal adverse effect on later dental health in older age. This study emphasizes the importance of early life experiences on dental health throughout later life.

Although exercising with others may have extra health benefits compared to exercising alone, few studies have examined the differences. We sought to examine whether the association of regular exercise to subjective health status differs according to whether people exercise alone and/or with others, adjusting for frequency of exercise. The study was based on the Japan Gerontological Evaluation Study (JAGES) Cohort Study data. Participants were 21,684 subjects aged 65 or older. Multivariable logistic regression models were used to examine the association. The adjusted odds ratios (ORs) for poor self-rated health were significantly lower for people who exercised compared to non-exercisers. In analyses restricted to regular exercisers the ORs for poor health were 0.69 (95% confidence intervals: 0.60-0.79) for individuals exercising alone more often than with others, 0.74 (0.64-0.84) for people who were equally likely to exercise alone as with others, 0.57 (0.43-0.75) for individuals exercising with others more frequently than alone, and 0.79 (0.64-0.97) for individuals only exercising with others compared to individuals only exercising alone. Although exercising alone and exercising with others both seem to have health benefits, increased frequency of exercise with others has important health benefits regardless of the total frequency of exercise.

Hypertension is an important risk factor for cardiovascular disease, the leading cause of mortality in the world. Although previous studies have focused on individual-level behavioral risk factors associated with hypertension, there has been little research on how interacting with others, that is social participation, affects hypertension. To address this research gap, this study examined the association between social participation and hypertension in Japan, a country with a high prevalence of hypertension possibly linked to rapid population aging. Data were used from 4582 participants aged more than 65 years who participated in the Japan Gerontological Evaluation Survey (JAGES) with blood pressure data collected during a health check-up. The frequency of participation in vertical organizations (characterized by hierarchical relationships) and horizontal organizations (characterized by non-hierarchical, egalitarian relationships) was measured by a questionnaire. In a Poisson regression analysis, participation in vertical organizations was not associated with hypertension, whereas participation in horizontal organizations at least once a month was inversely associated with hypertension (prevalence ratio: 0.941). This association remained significant after adjusting for social support variables, although further adjustment for health behaviors attenuated the association. As the frequency of going out and average time spent walking were both associated with hypertension, physical activity may be a possible pathway that connects social participation and hypertension. The results of this study suggest that expanding social participation programs, especially those involving horizontal organizations, may be one way to promote better health among older people in Japan.

No previous study has been able to examine the association by taking account of risk factors for dementia before and after the disaster. We prospectively examined whether experiences of a disaster were associated with cognitive decline in the aftermath of the 2011 Great East Japan Earthquake and Tsunami. The baseline for our natural experiment was established in a survey of older community-dwelling adults who lived 80 km west of the epicenter 7 mo before the earthquake and tsunami. Approximately 2.5 y after the disaster, the follow-up survey gathered information about personal experiences of disaster as well as incidence of dementia from 3,594 survivors (82.1% follow-up rate). Our primary outcome was dementia diagnosis ascertained by in-home assessment during the follow-up period. Among our analytic sample (n = 3,566), 38.0% reported losing relatives or friends in the disaster, and 58.9% reported property damage. Fixed-effects regression indicated that major housing damage and home destroyed were associated with cognitive decline: regression coefficient for levels of dementia symptoms = 0.12, 95% confidence interval (CI): 0.01 to 0.23 and coefficient = 0.29, 95% CI: 0.17 to 0.40, respectively. The effect size of destroyed home is comparable to the impact of incident stroke (coefficient = 0.24, 95% CI: 0.11 to 0.36). The association between housing damage and cognitive decline remained statistically significant in the instrumental variable analysis. Housing damage appears to be an important risk factor for cognitive decline among older survivors in natural disasters.

ObjectivesTo describe associations between tooth loss and changes in higher-level functional capacity. DesignProspective cohort study. SettingTwenty-four Japanese municipalities between 2010 and 2013. ParticipantsFunctionally independent community-dwelling persons aged 65 and older (N=62,333). MeasurementsSelf-reported number of teeth was used as an exposure variable. The outcome was changes in higher-level functional capacity measured using the Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC), which consists of three domains: instrumental activities of daily living, intellectual activity, and social roles. The TMIG-IC score ranges from 0 (lowest function) to 13 (highest function). All covariates were chosen from baseline demographic, socioeconomic, health behavior, and health variables based upon evidence from previous studies. Inverse-probability weighting (IPW) with propensity score and multiple linear regression, estimating nonstandardized coefficients () and 95% confidence intervals (CIs), were used. ResultsThe baseline response rate was 65.2%, and the follow-up rate was 70.1%. During the follow-up period, participants' TMIG-IC score declined by an average of 0.247 points (standard deviation: 1.446). The results showed a significant dose-response association between tooth loss and decline in higher-level functional capacity in multiple linear regression models. IPW models estimated the increment in TMIG-IC score (=0.170, 95% CI=0.114 to 0.227) if edentulous participants gained 20 or more natural teeth. ConclusionTooth loss is associated with future decline in higher-level functional capacity. IPW models suggest that treatment for tooth loss attenuates decline in higher-level functional capacity.

Hypertension is an important risk factor for cardiovascular disease, the leading cause of mortality in the world. Although previous studies have focused on individual-level behavioral risk factors associated with hypertension, there has been little research on how interacting with others, that is social participation, affects hypertension. To address this research gap, this study examined the association between social participation and hypertension in Japan, a country with a high prevalence of hypertension possibly linked to rapid population aging. Data were used from 4582 participants aged more than 65 years who participated in the Japan Gerontological Evaluation Survey (JAGES) with blood pressure data collected during a health check-up. The frequency of participation in vertical organizations (characterized by hierarchical relationships) and horizontal organizations (characterized by non-hierarchical, egalitarian relationships) was measured by a questionnaire. In a Poisson regression analysis, participation in vertical organizations was not associated with hypertension, whereas participation in horizontal organizations at least once a month was inversely associated with hypertension (prevalence ratio: 0.941). This association remained significant after adjusting for social support variables, although further adjustment for health behaviors attenuated the association. As the frequency of going out and average time spent walking were both associated with hypertension, physical activity may be a possible pathway that connects social participation and hypertension. The results of this study suggest that expanding social participation programs, especially those involving horizontal organizations, may be one way to promote better health among older people in Japan.

Previous studies have found an association between neighborhood characteristics (i.e., aspects of the physical and social environment) and the incidence of cardiovascular disease (CVD) and elevated CVD risk. This study investigated the relationship between neighborhood characteristics and CVD risk among older people in Japan where research on this association is scarce. Data came from the Japan Gerontological Evaluation Study project; questionnaire data collected from 3,810 people aged 65 years or older living in 20 primary school districts in Aichi prefecture, Japan, was linked to a computed composite CVD risk score based on biomarker data (i.e., hemoglobin A1c, systolic blood pressure, diastolic blood pressure, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and estimated glomerular filtration rate). A sex-stratified multilevel linear regression analysis revealed that for male participants, living in neighborhoods with a higher perceived occurrence of traffic accidents and reduced personal safety was associated with an elevated CVD risk (coefficient = 1.08 per interquartile range increase, 95% confidence interval [CI] = 0.30 to 1.86) whereas males living in neighborhoods with a higher perceived proximity of exercise facilities had a lower risk (coefficient = -1.00, 95% CI = -1.78 to -0.21). For females, there was no statistically significant association between neighborhood characteristics and CVD risk. This study suggests that aspects of the neighborhood environment might be important for CVD morbidity and mortality in Japan, particularly among men.

Background: We sought to evaluate the associations between frequency of daily laughter with heart disease and stroke among community-dwelling older Japanese women and men. Methods: We analyzed cross-sectional data in 20 934 individuals (10 206 men and 10 728 women) aged 65 years or older, who participated in the Japan Gerontological Evaluation Study in 2013. In the mail-in survey, participants provided information on daily frequency of laughter, as well as body mass index, demographic and lifestyle factors, and diagnoses of cardiovascular disease, hyperlipidemia, hypertension, and depression. Results: Even after adjustment for hyperlipidemia, hypertension, depression, body mass index, and other risk factors, the prevalence of heart diseases among those who never or almost never laughed was 1.21 (95% CI, -1.03-1.41) times higher than those who reported laughing every day. The adjusted prevalence ratio for stroke was 1.60 (95% CI, 1.24-2.06). Conclusions: Daily frequency of laughter is associated with lower prevalence of cardiovascular diseases. The association could not be explained by confounding factors, such as depressive symptoms.

Objective: Previous investigations on the impact of childhood socioeconomic status (SES) on depression have focused on middle-aged adults in Western countries. It is unknown whether childhood SES has a long-latency effect on the onset of depression among older adults. Design: Prospective cohort study. Setting: Data were from the Japan Gerontological Evaluation Study. Participants: We analyzed 10,458 individuals aged 65 years and older without depression (Geriatric Depression Scale <5) at baseline in 2010. Measurements: Participants rated their childhood SES at the age of 15 years according to standards at that time. We used binomial regression analyses with log link and with adjustment for known and potential risk factors to evaluate the risk of depression onset by 2013. Results: Overall, 13.9% of participants newly reported depression in 2013. After adjusting for age and sex, low childhood SES was positively associated with depression onset (adjusted risk ratio [ARR]: 1.44, 95% confidence interval [CI]: 1.23-1.69). The association decreased after adjustment for education (ARR: 1.33; 95% CI: 1.13-1.57). Even after adjustments for adult SES, current disease status, health behaviors, and social relationships, the association remained significant (ARR: 1.27; 95% CI: 1.08-1.50). The link was stronger among the younger old (6574 years) than the oldest old (>= 75 years). Conclusions: Low childhood SES, perhaps due to poverty in post-World War II, has a long-latency effect on the onset of depression among older Japanese adults. The impact of childhood SES on depression was weaker among the oldest old, suggesting survival effects for healthy older Japanese people.