Limitations in physical function and depressive symptoms among Chinese older men and women: the moderating effects of family ties and friendship ties

Abstract

Abstract Background Most studies exploring the moderating effects of social networks between limitations in physical function and depressive symptoms fail to distinguish the effect of different circle of social networks. The aim of this study was to examine the association among limitations in physical function, social networks and depressive symptoms, and explore the moderating effects of family ties and friendship ties among Chinese older men and women. Methods Data on 7770 participants (mean age = 69.12, SD = 7.50; men, 54.0%) from the baseline China Longitudinal Aging Social Survey were analysed. Linear regressions were used to evaluate the association among limitations in physical function, social networks, and depressive symptoms. The moderating effects of family ties and friendship ties and gender differences were also examined. Results Limitations in physical function were significantly associated with depressive symptoms (B = 0.275). More limitations in physical function were associated with poorer family ties (B=-0.042) and friendship ties (B=-0.195); the coefficient of limitations in physical function on friendship ties was significantly larger than that on family ties (χ2 = 38.41). Both family (B=-0.177) and friendship ties (B=-0.061) were associated with lesser depressive symptoms. The interaction between limitations in physical function and family ties was significantly negative in the total sample (B=-0.011), whereas the interaction between limitations in physical function and friendship ties was significantly positive among older women (B = 0.009). Female older adults with more limitations in physical function reported weaker family (B=-0.052, p < 0.01) and friendship ties (B=-0.210, p < 0.001). Male older adults with more limitations in physical function reported weaker friendship ties (B=-0.184, p < 0.001). However, the limitations in physical function of male older adults had a marginally significant effect on their family ties (B=-0.032, p < 0.1). Conclusions These findings highlight the different roles of family and friendship ties for older adults with various physical function status. Older adults, especially older women, who are healthy and can care for themselves should be encouraged to expand friendship ties to maintain their mental health. Moreover, the family and communities should provide enough support for older adults with limitations in physical function to reduce their depressive symptoms.