Association between serum uric acid and benign prostatic hyperplasia among Chinese men aged 45 years or older

Benign prostatic hyperplasia (BPH) is a leading cause of lower urinary tract symptoms in older men and imposes a growing health burden on aging populations. However, the association between serum uric acid levels and BPH remains inconclusive, and evidence from Chinese populations is scarce. This study investigates the prospective association between baseline serum uric acid (UA) levels and benign prostatic hyperplasia (BPH) among Chinese men aged 45 years or older, with particular attention to potential nonlinear and subgroup-specific associations. Baseline and follow-up data were obtained from the 2011 and 2015 waves of the China Health and Retirement Longitudinal Study, which used a multistage, stratified probability sampling design. Multivariable logistic regression was conducted to evaluate the association between baseline serum UA levels and BPH using three progressively adjusted models that included 11 covariates: age, education, residence, marital status, smoking status, alcohol consumption, body mass index, hypertension, history of cardiovascular disease, diabetes, and dyslipidemia. Restricted cubic spline regression was applied to examine potential nonlinear and dose-response associations. All analyses were performed using R version 4.3.2. Of the 4755 participants, 250 (5.26%) had BPH at follow-up. After adjustment for covariates, participants in the highest UA quartile (Q4) had higher odds of BPH (odds ratio [OR], 1.025; 95% confidence interval [CI], 1.006–1.045). Restricted cubic spline analysis indicated a U-shaped nonlinear association between serum UA levels and BPH (P for nonlinearity = 0.029). Serum UA levels above 5.92 mg/dL were associated with higher odds of BPH, while each interquartile range increase in UA corresponded to a 19.8% increase in the odds of BPH (OR, 1.198; 95% CI, 1.024–1.402). Receiver operating characteristic analysis yielded an area under the curve of 0.779 and identified 5.26 mg/dL as the optimal cutoff value. Subgroup analyses further showed a significant interaction between serum UA levels and residence. Baseline serum UA levels were nonlinearly associated with BPH at follow-up among Chinese men aged 45 years or older. However, the observational design precludes conclusions regarding causality or clinical utility. These findings should therefore be considered hypothesis-generating and require confirmation in studies using clinically validated BPH outcomes.