近藤 克則

OBJECTIVES: We examined long-term trajectories of depressive symptoms among older adults following exposure to the 2011 Great East Japan Earthquake and Tsunami. We further characterized the pre- and post-disaster social relationship factors that predicted membership in each trajectory group. METHOD: Data from four time points (including pre-disaster data) were used to analyze the depression trajectories of 2,033 survivors through a group-based trajectory model. Multinomial logistic analysis was used to investigate the social relationship factors (i.e., social interactions with neighbors, social support, social participation, and social cohesion) that predicted membership to each trajectory group. RESULTS: Five distinct trajectories of depressive symptoms were identified; stably not depressed (12.4%), increased after the disaster (14.2%), decreased after the disaster (8.8%), persistent mild depressive symptoms (28.1%) and persistent severe depressive symptoms (36.5%). Compared to those who were stably not depressed, those who experienced an increase in symptoms were more likely to experience housing damage and not to participate in social activities. Compared to those who were stably mildly depressed, those who experienced a decrease in symptoms had higher pre-disaster social interactions with neighbors as well as higher post-disaster social support. Adults with persistent severe symptoms were physically, psychologically, and socially vulnerable preceding the disaster. DISCUSSION: The study revealed the heterogeneity of older adults experiencing depressive symptoms in the wake of major disaster. Those who experienced increased symptoms after the disaster showed a chronic rather than temporary rise, while those with pre-disaster depressive symptoms showed sustained symptoms regardless of disaster-related trauma.

Serviced Housing for Older People (SHOP) is a community-based housing model in Japan that provides barrier-free apartments and support services for residents. Whether the SHOP model has positive effects on residents' health remains unclear. This follow-up study examines the association between living in SHOPs and functional decline. Using data from the Japan Gerontological Evaluation Study, we compared functional decline risks at one-year follow-up between older adults living in conventional housing (n = 2202) and SHOP residents (n = 160). Functional decline risk was assessed using the Kihon Checklist (KCL) and Care-Need Risk Assessment Scale (CNRAS). SHOPs residents had lower KCL and CNRAS scores than older adults living in conventional housing. In sensitivity analyses, these associations remained unchanged. The results, thus, showed that residing in SHOPs was associated with reduced functional decline; therefore, SHOPs designed to support residents' physical and social health could be important for supporting aging in place.

BACKGROUND: We sought to test the hypothesis that communities with a high degree of income inequality are ill-equipped to deal with crises. Specifically, we tested whether pre-disaster higher income inequality increases the risk of worse mental health conditions in the aftermath of disaster. METHODS: We examined the association between pre-disaster community income inequality and post-disaster mental health outcomes in a prospective cohort study of older adults (≥65 years) who survived the 2011 Great East Japan Earthquake. The baseline survey of participants (completed in 2010) predated the disaster by seven months. Survivors completed three waves of post-disaster surveys in 2013, 2016, and 2019. To assess the level of income inequality, the Gini index was calculated using individual income data in 2010 aggregated to 98 communities (range 0.05-0.50: median = 0.32) and categorized into tertiles (low, middle, high). Depressive symptoms and post-traumatic stress symptoms (PTSS) were assessed in the three post-disaster surveys using validated instruments. Multilevel analysis was conducted adjusting for pre-disaster characteristics. RESULTS: Higher levels of community income inequality were associated with higher PTSS scores across time (2013: β = 0.14, 95%CI = -0.01, 0.29; 2016: β = 0.16, 95%CI = 0.03, 0.29; 2019: β = 0.12, 95%CI = -0.01, 0.24). The association between income inequality and mental health was partly attenuated by adding the change in social capital to the model (2013: β = 0.14, 95%CI = -0.01, 0.29; 2016: β = 0.15, 95%CI = 0.03, 0.28; 2019: β = 0.11, 95%CI = -0.01, 0.22). CONCLUSION: Our findings suggest that pre-disaster income inequality may explain PTSS symptoms in the aftermath of a disaster, and the relation may be mediated by disaster-related change. Further study to reveal its mechanism is needed for the policy recommendation.

OBJECTIVE: This study aimed to evaluate the association between the Yokohama Walking Point Program, which promotes walking through feedback on step counts and incentives, and the extension of healthy life expectancy. METHODS: A total of 4298 individuals aged over 65 years who responded to the 2013 and 2016 surveys and who were not certified as needing long-term care in 2016 were included in this study. The participants were categorized into "non-participation," "participation without uploading," and "participation with uploading" groups based on their involvement and uploading of pedometer data. The objective variable was the occurrence of long-term care certification and deaths over the subsequent four years. A modified Poisson regression model was applied, adjusting for 15 variables before project initiation. RESULTS: A total of 440 participants (10.2 %) were included in the "participation with uploading" group and 206 (4.8 %) in the "participation without uploading" group. Compared with "non-participation," the risk ratio was 0.77 (95 % confidence interval (CI): 0.59-0.99) for "participation with uploading" and 1.02 (95 % CI: 0.75-1.38) for "participation without uploading". In the sensitivity analysis censoring death as an inapplicable outcome and considering functional decline, participation with uploading showed a risk ratio of 0.79 (95 % CI: 0.60-1.04) for the likelihood of functional decline. CONCLUSIONS: The use of pedometers and health point programs based on walking activity is associated with enhancing the health of older individuals participating in the program, representing a population-centric strategy targeting all citizens.

BACKGROUND: Social participation is crucial for healthy aging, improving physical and mental health, cognitive function, and quality of life among older adults. However, social participation tends to decline with age due to factors like loss of social networks and health issues. Mobile health apps show promise in promoting healthy behaviors among older adults, but their effectiveness in increasing social participation remains understudied. OBJECTIVE: This randomized controlled trial aimed to evaluate the efficacy of a mobile app called Encouragement of Social Participation (ESP, "Shakai Sanka no Susume;" Hitachi) in promoting social participation and physical activity among community-dwelling older adults. METHODS: The study recruited 181 community-dwelling adults aged 60 years or older from 2 municipalities in Japan and through a web-based research panel. Participants were randomly assigned to either the intervention group (n=87), which used the ESP app for 12 weeks, or the control group (n=94), which used only Google Fit. The ESP app incorporated features such as self-monitoring of social participation, personalized feedback, gamification elements, and educational content. Primary outcomes were changes in social participation frequency over the previous 2 months and changes in step counts, measured at baseline and week 12. Secondary outcomes included changes in specific types of social activities and subjective well-being. Data were analyzed using analysis of covariance and linear mixed-effects models. RESULTS: The intervention group showed a significantly greater increase in social participation frequency compared with the control group (adjusted difference 3.03; 95% CI 0.17-5.90; P=.04). Specifically, the intervention group demonstrated higher frequencies of participation in hobbies (adjusted difference: 0.82; 95% CI 0.01-1.63) and cultural clubs (adjusted difference 0.65; 95% CI 0.07-1.23) compared with the control group. However, there were no significant differences in weekly step counts between the groups. Subgroup analyses suggested potentially larger effects among participants who were older than 70 years, female, had lower educational attainment, and were recruited from community settings, although only females and the lower educational attainment subgroups demonstrated 95% CIs that did not encompass zero. CONCLUSIONS: The ESP mobile app effectively promoted social participation among community-dwelling older adults, particularly in hobbies and cultural club activities. However, it did not significantly impact physical activity levels as measured by step counts. These findings suggest that mobile apps can be valuable tools for encouraging social engagement in older populations, potentially contributing to healthy aging. Future research should focus on optimizing app features to maintain long-term engagement and exploring strategies to enhance physical activity alongside social participation. TRIAL REGISTRATION: University Medical Information Network Clinical Trial Registry UMIN000049045; https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000055781.