Association between the number of social roles and self-rated health: mediation effect by ikigai and the size of close social networks.

Abstract

Background: Health effects of multiple role occupancy and their mechanism are not fully addressed. We examined (1) the association between the number of social roles and self-rated health (SRH) and (2) the mediation effects of ikigai (the sense of life worth living) and the size of close social networks to the association.

Methods: We analysed the cross-sectional baseline questionnaire data of the Japan Public Health Center-based Prospective Study for the Next Generation (JPHC-NEXT) of 22 180 men and 26 616 women in age 40-59 years. The independent variable was the number of social roles, counting five social roles as a spouse, parent, child, worker and a role in a community. The dependent variable was poor SRH. Logistic regression was used to estimate the ORs for poor SRH by the number of social roles and to test linear trends. Mediation analyses were conducted to estimate the proportion mediated by ikigai and the size of close social networks.

Results: Compared with people with 0-1 social role, those who had two or more roles had a lower OR of poor SRH in both men and women. There was a linear inverse trend in the association; people having the largest (5) versus lowest (0-1) number of social roles had the lowest ORs: 0.55 (95% CI 0.46 to 0.66) in men and 0.72 (95% CI 0.61 to 0.86) in women. The estimated proportion mediated by ikigai was over 50%, whereas the size of close social networks mediated the association by approximately 20%.

Conclusion: An inverse association between the number of social roles and poor SRH and mediation effects of ikigai and the size of close social networks were identified. Having even one more social role might benefit subjective health via increased ikigai and the size of close social networks.