Partner Depression and Risk of Incident Depression Among Middle-Aged and Older Chinese Adults: A Repeated Person-Interval Analysis of CHARLS

Abstract Background Spousal depressive symptoms are often correlated, but whether partner depression is associated with subsequent incident depression among initially non-depressed spouses remains unclear. We examined this association among middle-aged and older Chinese couples using a repeated incident-risk framework. Methods Data were obtained from five waves (2011–2020) of the China Health and Retirement Longitudinal Study. Across four consecutive intervals, individuals with CES-D-10 scores < 10 at interval baseline were considered at risk, and partner depression (CES-D-10 ≥ 10) was examined in relation to incident depression at the subsequent wave. Modified Poisson generalized estimating equations were used to estimate risk ratios (RRs) and 95% confidence intervals (CIs). Results The analysis included 23,886 person-interval observations from 11,612 recipients, with 4,969 incident depression events. Partner depression was associated with subsequent incident depression after full adjustment, including the recipient's interval-specific baseline CES-D score (RR = 1.134, 95% CI 1.072–1.200). Baseline CES-D was strongly associated with incident depression (RR per point = 1.168, 95% CI 1.157–1.179), but did not modify the association with partner depression ( P for interaction = 0.696). Associations appeared stronger for wife-to-husband than husband-to-wife direction, although sex heterogeneity was not statistically significant ( P for interaction = 0.053). Under stricter temporal ordering, the association was attenuated and no longer statistically significant (RR = 1.092, 95% CI 0.963–1.239). Conclusions Partner depression was prospectively associated with a modestly higher risk of incident depression. However, attenuation under stricter temporal ordering cautions against interpreting this association as direct spouse-to-spouse transmission.