Association between ZJU index and kidney stone prevalence in the Chinese adult population: a retrospective propensity score-matched analysis.

The study aimed to explore the association between the ZJU (Zhejiang University) index and the prevalence of kidney stones in Chinese adults. Electronic health records of individuals undergoing routine physical examinations at Wuhu Second People's Hospital between January 2021 and June 2024 were retrospectively analyzed. Participants were divided into kidney stone recurrence and non-recurrence groups. Data on biochemical parameters, hypertension, and diabetes history were collected, and group differences were assessed using the chi-square test or Kruskal-Wallis rank-sum test. Logistic regression, propensity score matching, and dose-response curve modeling were used to evaluate the relationship between the ZJU index and kidney stone prevalence. Among 5,104 participants aged over 18 years, 462 were diagnosed with kidney stones. After adjusting for confounders, a higher ZJU index was identified as an independent risk factor for kidney stone prevalence (odds ratio [OR] = 1.05, 95% confidence interval [CI]: 1.02-1.08). Propensity score-matched analysis further confirmed this association (OR = 1.09, 95% CI: 1.04-1.13). Dose-response analysis revealed a positive linear relationship between the ZJU index and kidney stone recurrence. These findings suggest that elevated ZJU index levels are associated with a higher prevalence and recurrence of kidney stones, highlighting its potential as a clinical tool for identifying and managing at-risk patients.