Social capital, depressive symptomatology, and frailty among older adults in the western areas of China

We aimed to explore the relationship between social capital (SC) and frailty, and the mediation role of depressive symptoms in this relationship. A cross-sectional study among 2,591 older adults aged ≥60 years old was conducted from September 2020 to May 2021. SC, depressive symptoms, and frailty were measured using the social capital scale, the 9-item patient health questionnaire, and the FRAIL scale, respectively. The mediation model was tested by Bootstrap PROCESS. After controlling for socio-demographical covariates, the SC was negatively correlated with frailty (r = -0.07, P = 0.001), and depressive symptomatology (r = -0.08, P<0.001); while the depressive symptomatology was positively correlated with frailty (r = 0.33, P<0.001). Logistic regression results showed that SC was associated with a lower risk of frailty (OR = 0.94; 95% CI: 0.92–0.97; P<0.001). Depressive symptomatology partially mediated (explained 36.4% of the total variance) the association between SC and frailty. Those findings suggest that SC may protect older adults from frailty by reducing depressive symptoms. Prevention and intervention implications were also discussed.