Combined effects of depression and visual impairment on cardiovascular disease incidence in a Chinese population-based cohort.

Depression and visual impairment (VI) are prevalent in aging populations and known risk factors for cardiovascular disease (CVD). Their combined impact on CVD incidence remains poorly defined. This study investigated the individual and combined effects of depression and VI on incident CVD in a large Chinese cohort. We included 18,633 participants aged ≥ 45 from the China Health and Retirement Longitudinal Study (2011–2018). Participants were categorized into four groups: control, depression only, VI only, and both. Incident CVD was identified during follow-up. Cox regression was used to estimate hazard ratios (HRs). In the fully adjusted model, all three exposure groups had significantly higher CVD risk than the control group. The highest risk was for depression only (HR: 1.60; 95% CI: 1.36–1.89), followed by co-occurring depression and visual impairment (HR: 1.56; 95% CI: 1.40–1.73), and visual impairment only (HR: 1.25; 95% CI: 1.13–1.38). A significant negative multiplicative interaction was observed (HR for interaction: 0.78; 95% CI: 0.65–0.93; p = 0.006). Depression and VI are independently associated with increased CVD risk. Their co-occurrence shows an antagonistic interaction, with combined risk not exceeding that of depression alone. Screening for depressive symptoms in older adults, especially those with VI, may aid CVD prevention.