Association Between Socioeconomic Status and Chronic Diseases Among Middle‐Aged and Older Adults in China

ABSTRACT Socioeconomic status (SES) disparities may contribute to variations in the rates of chronic diseases. With advancing age, individuals are increasingly susceptible to multiple concurrent chronic conditions, known as multimorbidity. This study investigated the relationship between SES and the prevalence of specific chronic diseases, along with multimorbidity, in middle‐aged and older adults in China. This cross‐sectional analysis was based on data from the 2015 and 2020 waves of the China Health and Retirement Longitudinal Study (CHARLS). Participants aged 45 years with complete data on chronic diseases were enrolled in this study. Multivariable logistic regression models were constructed to examine the correlation between SES, education level, area of residence, and multimorbidity. A total of 17,234 participants were included, comprising 9162 (53.2%) women and 8072 (46.8%) men. A positive association was observed between higher SES and elevated odds of multimorbidity (OR, 1.07; 95% CI, 1.04–1.09; p < 0.001), as well as certain chronic conditions. A higher level of educational attainment demonstrated a significant positive correlation with a greater prevalence of multimorbidity. Urban residence was significantly associated with elevated odds of multimorbidity (OR, 1.17; 95% CI, 1.09–1.26; p < 0.001). Subgroup analyses showed robust associations between SES and multimorbidity across most strata. Higher SES, educational attainment, and urban residence were positively associated with the prevalence of multimorbidity in adults aged ≥ 45 years in China. These associations may partly reflect disparities in diagnostic opportunities rather than differences in true disease burden. Further longitudinal studies are needed to track the evolving relationship between SES and multimorbidity over time.