Volunteer group participation and subsequent health and well-being among older adults in Japan: An outcome-wide longitudinal approach

Background: Prior studies have underscored the importance of studying volunteering in the East Asian context. However, no study has conducted a holistic assessment of the relationship between volunteering and the multidimensional health and well-being outcomes of East Asian populations using a strong study design for causal inference. To address this gap, this study examined the associations between volunteer group participation and the subsequent health and well-being of Japanese older adults. Methods: Three waves of data (2013, 2016, and 2019), obtained from the Japan Gerontological Evaluation Study -a nationwide cohort study of physically and cognitively independent older adults, aged >= 65 years, in Japan -were utilized. Exposure was evaluated as the frequency of volunteer group participation: >= 1/week, 13 times a month, a few times a year, and none (2016). As outcomes, 40 indicators of health and well-being were assessed across seven domains (2019): physical/cognitive health, health behaviors, mental health, subjective well-being, social well-being, pro-social/altruistic behaviors, and cognitive social capital. We included 47,318 respondents for four outcomes (death, dementia, and functional disability [any level and level 2 or greater]) and 34,187 respondents for the 36 other outcomes. Results: More frequent volunteering (>= 1/week) was associated with higher social well-being outcomes, more frequent pro-social/altruistic behaviors and outings, and fewer depressive symptoms, even after considering multiple testing. Conclusion: Throughout the three-year follow-ups, volunteer group participation was beneficial for depressive symptoms, social well-being, and other proximal outcomes.