Abstract: Objective This study aimed to investigate the association between socioeconomic status (SES) and the risk of prevalent chronic diseases among a natural population cohort in Southern China, with the objective of providing evidence-based recommendations for the prevention and control of chronic diseases in this region. Methods Utilizing baseline data from a prospective cohort study on chronic diseases in a natural population of Southern China, a composite SES score was constructed using principal component analysis, incorporating educational attainment, occupational classification, and household income. Participants were subsequently categorized into high and low SES groups based on this score. Poisson regression analysis was employed to examine the association between SES and the prevalence of various chronic diseases. Furthermore, stratified analyses were conducted to test for potential effect modification by gender, age, Body Mass Index (BMI), smoking status, and alcohol consumption. Results A total of 87 292 adults aged 25-89 years were included in the analysis, of whom 34 029 (39.0%) were male. The overall prevalence of having at least one of four common chronic diseases (hypertension, diabetes, coronary heart disease, and stroke) was 25.34%, accounting for 22 124 cases. After adjusting for potential confounding variables, no significant association was observed between SES and the composite prevalence of common chronic diseases, hypertension, diabetes, or coronary heart disease (all P>0.05). However, a significant inverse association was identified between SES and the prevalence of stroke (RR=0.84, 95% CI: 0.76-0.93). Stratified analyses revealed heterogeneous effect modification in the association between SES and various chronic diseases across different strata of gender, age, BMI, smoking status, and alcohol consumption. Conclusion Among adults in Southern China, socioeconomic status was not significantly associated with the prevalence of most common chronic diseases, with the exception of stroke, for which an inverse relationship was observed. The heterogeneity of the association between SES and chronic diseases across different subpopulations suggests that prevention and control strategies for chronic diseases should be tailored to the specific life-stage and behavioral characteristics of targeted groups.

Key words: Socioeconomic status, Population of South China, Chronic diseases