Association between Increasing Social Capital and Decreasing Prevalence of Smoking at the Municipality Level: Repeated Cross-Sectional Study from the JAGES

As smoking cessation is crucial for both individual and public health, this study aimed to elucidate the association between changes in social capital and in terms of smoking at the level of municipal units in Japan. Using repeated cross-sectional data from the Japan Gerontological Evaluation Study, we analyzed data from adults aged 65 years or older from 69 municipal units that participated in two survey waves. We received valid responses from 91,529 and 86,403 older people in 2013 and 2019, respectively, and aggregated all variables by municipal units. For the dependent variable, we used the units' prevalence of smoking for both years. The independent variables were the percentages of social capital indicators, such as social participation, social cohesion, and reciprocity for each of the 69 municipal units. The mean prevalence of smoking increased from 9.7% in 2013 to 10.2% in 2019. Multiple regression analysis revealed that increases in the percentages of sports group participation, receiving emotional and instrumental social support, and reciprocity were significantly associated with decreased prevalence of smoking, after we adjusted for confounding variables. This study indicates that building social capital might be useful in promoting smoking cessation and that its indicators could be useful in monitoring efforts.