Depressive symptoms and low cognitive function as dual pathways linking childhood interparental relationships to late-life ADL disabilities

Early-life adversity represents a potent risk factor for late-life affective disorders, yet how these psychological consequences relate to late-life physical disability remains incompletely understood. The present study aimed to examine whether depressive symptoms, alongside cognitive function, may serve as pathways linking childhood interparental relationships to late-life Activities of Daily Living (ADL) disability in older Chinese adults. Using data from 5,041 disability-free adults aged ≥ 60 years enrolled in the China Health and Retirement Longitudinal Study, we applied marginal structural models for mediation analysis to estimate the total effect of poor childhood interparental relationships on ADL disability at follow-up, as well as the distinct and joint indirect effects operating through late-life depressive symptoms and low cognitive function, to our knowledge, which have rarely been examined simultaneously in this population. Poor childhood interparental relationships were associated with 37% higher odds of developing late-life ADL disability (OR = 1.37, 95% CI: 1.15–1.63). In the mediation analysis, late-life depressive symptoms emerged as the principal psychological mediator, independently accounting for 11.61% (95% CI: 4.18%–21.41%) of the total effect. Low cognitive function also contributed independently to this pathway, and when both mediators were considered jointly, they explained 23.86% (95% CI: 12.30%–39.25%) of the total effect. Notably, a significant controlled direct effect persisted after accounting for both mediators (OR = 1.27, 95% CI: 1.05–1.53), indicating that most of the association was not explained by the two mediators examined and that other, unmeasured pathways remain to be identified. Childhood family adversity may be associated with late-life physical health, with these associations partly operating through distinct and potentially modifiable affective and cognitive pathways. Our findings suggest that depressive symptoms may serve as an important and potentially modifiable mediator, which, in concert with cognitive decline, may contribute to the progression toward ADL disability. These findings may have implications for the design of integrated mental health and geriatric care interventions targeting older adults with histories of early-life adversity. However, the mechanisms linking childhood family adversity to late-life disability require further investigation, ideally with biological and repeated psychosocial measures. Not applicable.