Abstract
Stroke, as the second leading cause of death globally, is characterized by high disability and mortality rates and urgently needs biomarkers for risk stratification. This study aims to use data from the China Health and Retirement Longitudinal Study (CHARLS) cohort to explore the association of the uric acid to HDL-C ratio (UHR), BMI with incident stroke. A total of 3756 participants aged 45 and above without a history of stroke were included from the CHARLS data from 2011 to 2020. Stroke events were confirmed through follow up data. UHR was calculated as the ratio of serum uric acid (mg/dL) to high density lipoprotein cholesterol (mg/dL). Statistical methods such as the Cox proportional hazards regression model, restricted cubic spline analysis, mediation effect test (Bootstrap method), and and multiplicative and additive interactions analysis were used to systematically evaluate the association of the combined UHR and BMI indicators with stroke risk. The UHR was significantly associated with stroke risk (HR = 1.03, p = 0.005), with the highest UHR group having 1.61 times the risk of the lowest group (p = 0.003). Subgroup analysis indicated that this association was significant in the non-diabetic population (p < 0.001) but not in the diabetic population (interaction p = 0.002). UHR mediated 18% of the association between BMI and stroke risk (95% CI 6.7-38%). No significant multiplicative and additive interactions were found between BMI and UHR on incident stroke.Restricted cubic spline analysis showed an approximately linear dose-response relationship between UHR and stroke risk (p for non linearity = 0.917). The study results indicate that UHR is significantly and positively correlated with stroke risk, and its value in stroke risk stratification is significantly enhanced when used in combination with BMI.