How a healthy lifestyle mediates socioeconomic inequities in healthy ageing and life expectancies: A 20-year cohort of older adults

Lower socioeconomic status (SES) is associated with various adverse health outcomes, but its association with healthy ageing is less known, and whether adherence to a healthy lifestyle at late-life years can reduce socioeconomic disparities in health requires further investigation. In a 20-year cohort of 33 541 older adults aged ≥65 years across 23 provinces in China, we investigated socioeconomic disparities in mortality and unhealthy ageing considering physical, cognitive, mental, visual, and hearing functions, and evaluated whether adherence to a healthy lifestyle at late-life years can reduce these health disparities. We categorized SES into low, medium, or high using latent class analysis based on education level, financial status, and occupation, and established the healthy lifestyle score by never smoking, no heavy alcohol consumption, regular physical and leisure activity, and a healthy diet. Compared with older adults of high SES, those of low SES had increased risks of all-cause mortality and unhealthy ageing, with adjusted hazard ratios (HR) and 95% confidence intervals (CI) of 1.25 (1.17, 1.33) and 1.46 (1.33, 1.60), respectively. Overall, a healthy lifestyle mediated 20.5% (16.4, 24.7) and 16.4% (12.0, 20.9) of socioeconomic inequity in all-cause mortality and unhealthy ageing, respectively. In low, medium, and high SES subpopulations, the healthiest lifestyle group had 3.18 (2.69, 3.67), 3.76 (2.85, 4.67), and 5.65 (3.75, 7.55) more years of total life expectancy, and 1.40 (1.06, 1.74), 2.73 (2.09, 3.37), and 3.90 (2.64, 5.16) more years of healthy life expectancy at age 65, respectively, compared to the least healthy group. The findings underscored the urgent need for tailored, accessible interventions in low-SES populations to mitigate health inequities and reinforced the importance of healthy lifestyle promotion, even at late-life years, for healthy ageing and longevity.