Heterogeneity in the associations of community gathering place participation with healthy ageing

Extending healthy life expectancy is a critical policy priority in aging societies worldwide. In Japan, community gathering places (CGPs) for older adults, which are resident-led group activities conducted in accessible local spaces. While prior studies have suggested benefits of CGPs participation, most evidence is limited to single municipalities. The potential heterogeneity in benefits across sociodemographic subgroups remains unclear.

We analyzed data from 55,982 community-dwelling older adults aged 65 years or older across 21 municipalities participating in the Japan Gerontological Evaluation Study. We linked pre-baseline data from 2016, baseline data from 2019, and follow-up data from 2019 to 2022. Our outcome was loss of healthy life expectancy, defined as incident functional disability or death. Our exposure was CGPs participation. Logistic regression models estimated odds ratios, adjusting for pre-exposure covariates. We applied a moderator-wide approach to assess effect modification by sociodemographic characteristics.

Participation in CGPs was associated with lower odds of the incidence functional disability or death (OR, 0.88; 95 % CI, 0.79-0.98). Stratified analyses suggested stronger associations in subgroups including women, older adults (≥75), individuals with lower education or income, unemployed, living alone and rural residents. However, formal tests did not detect statistically significant effect modification.

Participation in CGPs may promote healthy aging across diverse older populations. These findings support CGPs as an equitable and scalable strategy for improving population health. Future research should involve longer follow-up periods and explore more dimensions of heterogeneity.