Predictive role of depressive symptoms on frailty and its components in Chinese middle-aged and older adults: a longitudinal analysis

To investigate the cross-sectional and longitudinal associations between depressive symptoms and the prevalence of frailty and its components in a nationally representative sample of middle-aged and older Chinese adults. The China Health and Retirement Longitudinal Study (CHARLS) provided data on 2581 (after inclusion and exclusion criteria) adults aged ≥ 45 years. Every two years, face-to-face, computer-aided personal interviews (CAPI), and structured questionnaires were used to follow up with the respondents. The Chinese version of the Center for Epidemiologic Studies-Depression Scale (CES-D) was used to evaluate depressive symptoms, and the Fried criteria were used to measure frailty. The odds ratio (OR) and 95% confidence interval (CI) for the association of exposure (depressive symptoms at baseline) with the onset of the outcome (frailty and its components) in the individuals at baseline were analyzed by binary logistic regression. At baseline, 11.62% of participants had frailty, and 57.92% had depressive symptoms. In the cross-sectional analysis, depressive symptoms (OR = 5.222, 95%CI 3.665-7.442) were associated with frailty. In the longitudinal analysis, after adjusting for the full set of covariates among participants free of baseline frailty, depressive symptoms were significantly associated with incident frailty during the short term (OR = 2.193, 95%CI 1.324-3.631) and the long term (OR = 1.926, 95%CI 1.021-3.632). Meanwhile, depressive symptoms were associated with an increased risk of weakness (OR = 1.990, 95%CI 1.250-3.166), slowness (OR = 1.395, 95%CI 1.044-1.865), and exhaustion (OR = 2.827, 95%CI 2.150-3.719) onset during the short-term. Depressive symptoms were associated with an increased risk of exhaustion (OR = 2.869, 95%CI 2.004-4.109) onset during the long-term. Among middle-aged and older adults, depressive symptoms could predict frailty during 2 years of follow-up and 4 years of follow-up. When considering potential confounding factors, depressive symptoms were considered a predictor of weakness, slowness, and exhaustion. Interventions aimed at preventing depressive symptoms may be beneficial in reducing frailty and its components.