Suggesting Indicators of Age-Friendly City: Social Participation and Happiness, an Ecological Study from the JAGES

Ascertaining progress in building age-friendly cities (AFCs) requires community diagnostic indicators. This study examines the relationship between social participation and happiness at the municipal level. The data from the Japan Gerontological Evaluation Study (JAGES) from 2013, 2016, and 2019, comprising 442,079 older people from 289 municipalities, are used. We also employ linear mixed-effects models to evaluate the association between social participation and happiness. In these models, we adjust for seven variables as potential confounders. This study reveals that the higher the social participation, except for neighborhood association, the higher the state of happiness (B = 0.14–0.30). Our study suggests that social participation is useful, as a community diagnostic indicator, for monitoring the progress of building AFCs, developing strategies, and creating evidence.