Sex-specific associations of traditional and novel anthropometric indices with incident kidney stone disease: a 10-year longitudinal cohort study.

Excess adiposity and altered body fat distribution are increasingly recognized as important contributors to metabolic disorders, including kidney stone disease (KSD). However, how to best assess obesity-related KSD risk and the temporal relationship remain unclear. This 10-year retrospective longitudinal cohort study included participants undergoing annual health examinations. Data on demographics, KSD, and six anthropometric indices were collected. Cox regression stratified by sex was used. Model 1 examined the associations of baseline indices with 10-year incident KSD, while Model 2 examined the associations of the 5-year mean indices with incident KSD during years 6-10. Kaplan-Meier survival curves compared event-free probability. Restricted cubic spline regression assessed non-linear relationships. Sex-stratified 10-wave cross-lagged panel models examined overall adjacent-wave temporal associations between anthropometric indices and KSD across the ten annual assessments. A total of 24,418 participants were included. In Model 1, high baseline body mass index (BMI) was significantly associated with a higher 10-year risk of KSD among females (HR, 1.35; 95% CI, 1.03-1.78), while waist circumference (WC), waist-to-hip ratio (WHR), BMI, weight-adjusted-waist index (WWI) and body roundness index (BRI) were significantly associated with incident KSD in male participants (all HRs, 1.06-1.11; P<0.001). Survival analysis showed higher event-free probability in females with lower WHR and BMI (all P<0.05), and in males with lower BMI, WHR, WC, WWI, and BRI (all P<0.001). In Model 2, all indices except a body shape index (ABSI) were significantly associated with subsequent 5-year KSD risk in males (all P<0.001), whereas no significant associations in females. Cross-lagged panel analyses suggested significant temporal associations of WC, BMI, WWI, WHR, and BRI with subsequent KSD in males, whereas no such associations were observed in females. Sex-specific anthropometric patterns were observed in relation to KSD. Multiple indices of overall and central adiposity were consistently associated with KSD in males, whereas the associations were less consistent in females. Anthropometric indices alone may therefore be insufficient to characterize KSD risk in females, highlighting the potential contribution of additional metabolic, hormonal, and other sex-specific factors.