Serum uric acid levels and incident stroke: A longitudinal nationwide cohort study based on CHARLS data in China

Evidence from nationally representative cohort studies based on the Chinese population regarding the relationship between uric acid (UA) and the incidence of stroke remains insufficient. Using data from the China Health and Retirement Longitudinal Study (CHARLS), this study aimed to address this gap.

We enrolled 9585 eligible participants. Kaplan-Meier curves were used to estimate the cumulative incidence of stroke. Cox proportional hazards models were used to analyze the association between serum UA levels and stroke risk. Sensitivity analysis was conducted using a competing risk model. A restricted cubic spline (RCS) was applied to explore potential dose-response relationships. Subgroup analyses assessed the interaction effects within population subgroups. During the 9-year follow-up period, 650 participants (6.8%) experienced an incident stroke. Kaplan-Meier analyses showed a differential cumulative stroke incidence across the UA-level groups. A linear dose-response relationship was observed between UA levels and stroke onset in all covariate-adjusted models (P values for nonlinearity >0.05). In the fully adjusted Cox model, each 1 mg/dL UA increment was associated with a 15% elevated stroke risk (hazard ratio [HR] = 1.15, 95% confidence interval [CI]: 1.09-1.22). Consistent results were replicated in the competing risk analyses. Significant interaction effects emerged in the sex and smoking subgroups (P for interaction = 0.046 and 0.045, respectively).

Our study demonstrated a linear dose-response relationship between serum UA levels and stroke incidence in adults aged ≥45 years, specifically significant in males and smokers but absent in females and non-smokers.