Association of depressive symptoms with marital status among the middle-aged and elderly in Rural China–Serial mediating effects of sleep time, pain and life satisfaction

This study aimed to explore the potential effect of sleep time, pain and life satisfaction on the association between marital status and depressive symptoms. This study included 9780 individuals aged 45 years and older from the China Health and Retirement Longitudinal Study (CHARLS) in 2015. Regression analysis was used to explore the mediating effect of targeted mediators on the association between marital status and depressive symptoms. Bootstrap method was used to examine the statistical significance of the mediating effects. In the mediation model incorporating sleep time, pain and life satisfaction as mediators between marital status and depressive symptoms, the direct effect of marital status on depressive symptoms was statistically significant (p < 0.001, 95% CI = 0.699, 1.428). Approximately 39.28% (Indirect effect/Total effect) of the significant association between marital status and depressive symptoms was mediated by sleep time, pain, and life satisfaction. Limitations include non-representativeness other than rural residents and unclear cause-and-effect relationship. Those separated/divorced/widowed/never-married middle-aged and elderly individuals might be high risk population of depressive symptoms. It could be possible to relieve the depressive symptoms of these people by guaranteeing sufficient sleep, relieving pain and improving life satisfaction.