Longitudinal trajectories of depressive symptoms and respiratory health risk in middle-aged and older Chinese adults: A nationally representative prospective landmark cohort study.

BACKGROUND: Depressive symptoms are dynamic, but their longitudinal patterns in relation to chronic respiratory disease (CRD) remain unclear. We examined whether depressive symptom trajectories were associated with incident CRD in middle-aged and older Chinese adults. METHODS: Data from the China Health and Retirement Longitudinal Study were analyzed using a 2015 landmark design. Depressive symptoms were assessed with the 10-item Center for Epidemiologic Studies Depression Scale in 2011, 2013, and 2015 among participants free of self-reported physician-diagnosed CRD through 2015. Incident CRD was assessed in 2018 and 2020. Group-based trajectory modeling was used to identify symptom patterns, and multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Among 7261 participants, 611 (8.4%) developed CRD. Five trajectories were identified: low-stable (64.4%), decreasing (12.1%), fluctuating (5.3%), increasing (11.2%), and high-stable (7.0%). Compared with the low-stable group, all four non-low-stable trajectories were associated with higher odds of incident CRD after full adjustment (ORs 1.32-2.32), with the strongest association in the high-stable group (OR 2.32, 95% CI 1.75-3.06). At single assessments, 14.1%-18.6% of participants with CES-D-10 scores <10 belonged to non-low-stable trajectories. Associations were broader for CRD and chronic lung disease than for asthma. Persistently high somatic and affective-cognitive trajectories were also associated with CRD and chronic lung disease. Findings were robust in sensitivity analyses. CONCLUSION: Depressive symptom trajectories were associated with CRD and captured heterogeneity not fully reflected by single-time assessments. Repeated assessment may help identify middle-aged and older adults at elevated respiratory risk.