To investigate the association between the atherogenic index of plasma(AIP) and the risk of kidney stones in the Chinese population undergoing health examinations, providing evidence-based support for risk stratification and precise prevention and control.

Using cross-sectional data from 88 001 healthy individuals who underwent health examinations at Yangzhou University Affiliated Hospital in 2022, we analyzed the association between AIP and the risk of kidney stones using a multivariable logistic regression model. We also explored the nonlinear relationship using restricted cubic splines and threshold saturation effect models. The robustness of the results was assessed through sensitivity analysis, subgroup analysis, and E-value assessment.

A total of 88 001 participants with complete data were included in this study. The overall prevalence of kidney stones was 6.82%, and the prevalence of kidney stones increased with increasing AIP (P<0.001).Multivariable logistic regression analysis showed that, after adjusting for relevant confounding factors, the highest AIP group had 29% higher odds of kidney stones than the lowest AIP group (OR=1.29; 95% CI: 1.17-1.42; P<0.001). AIP exhibited a nonlinear association with kidney stone risk, with a significant increase in risk when AIP<0.27 (OR=1.89; 95% CI: 1.62-2.19; P<0.001), while the trend of increased risk slowed when AIP≥0.27 (OR=1.23; 95% CI: 1.10-1.37; P<0.001). Stratified analysis revealed that the association between AIP and the risk of kidney stones was more pronounced in subgroups of participants aged ≥60 years, men, and those with diabetes and hypertension. Sensitivity analyses and interaction tests indicated that the positive correlation between AIP and kidney stone risk was stable and consistent across the population (all P>0.05).

This study suggests that AIP is associated with an increased risk of kidney stones. AIP may serve as a practical biomarker for assessing kidney stone risk, particularly guiding early interventions such as lipid control and improving insulin resistance. Future prospective studies are needed to validate its causal mechanisms and threshold intervention effects.