A Cohort of Sociodemographic and Health-Related Risk Factors for All-Cause Mortality in Middle-Aged and Older Adults in China

Background: Physical inactivity is a major contributor to increased mortality among aging populations, especially in middle-aged and older adults. Methods: Data were derived from the China Health and Retirement Longitudinal Study (CHARLS, 2011–2020). Participants self-reported their physical activity frequency, categorized as low (≤1 day/week), medium (2–4 days/week), or high (≥5 days/week). All-cause mortality was tracked through verified records. Cox proportional hazards models were used to estimate hazard ratios (HRs), with adjustments for demographics, lifestyle factors, and baseline health conditions. Results: A total of 2092 participants (mean age = 63.7 ± 10.4 years) were included in the final analytic sample. Higher physical activity frequency was significantly associated with lower mortality in unadjusted models. Participants engaging in activity ≥5 days/week had a 67% reduced mortality risk compared to the low-frequency group (HR = 0.33, p < 0.001). However, after adjusting for health-related covariates, the protective effect was attenuated and no longer statistically significant. In the fully adjusted model, advanced age, current smoking, and ADL limitations emerged as the strongest independent risk factors for mortality, while being married and residing in a rural area were significantly protective effects. Conclusions: The association between frequent physical activity and reduced mortality risk among Chinese older adults is profoundly mediated by baseline health status and functional capacity. These findings highlight the importance of integrated, multifactorial public health interventions that address chronic disease management and functional rehabilitation alongside physical activity promotion.