Patient characteristics and influencing factors of CKD, CVD and their comorbidities in the middle-aged and elderly population in China

Background and aims: Chronic Kidney Disease (CKD) and Cardiovascular Disease (CVD) are significant public health concerns with high morbidity and mortality. The relationship between CKD and CVD and their influencing factors in Chinese middle-aged and elderly people remains underexplored. We hypothesize that some socio-demographic factors, lifestyle factors, and physical condition factors significantly influence the prevalence and comorbidity of CKD and CVD. Methods We used data from the China Health and Retirement Longitudinal Study (CHARLS), focusing on adults aged 45 and above. CKD stages were defined based on estimated glomerular filtration rate (eGFR), while CVD status was determined through self-reported diagnosis. Factors considered in the analysis included socio-demographic variables (age, gender, household registration, education, marital status), lifestyle behaviors (smoking, drinking), and physical conditions (body mass index (BMI), blood pressure, blood sugar, blood lipids, serum uric acid). Results CVD risk begins in early stages of CKD in the Chinese population. Individuals with characteristics such as hypertension, diabetes, non-rural household registration, abnormal BMI, or low education levels are significantly more likely to develop CKD and its comorbidity with CVD. Both low and high BMI were associated with increased CKD and CVD risk, with low BMI linked to reduced CVD risk in CKD patients. Conclusion Socio-demographic and physical factors are critical in managing and preventing CKD and CVD comorbidities. Public health strategies should focus on non-rural and lower-educated populations in Chinese middle-aged and elderly people, and further research is needed to explore mechanisms and interventions.