The aim of this study was to investigate the relationship between cardiometabolic index (CMI) and kidney stones.

The data for the large sample in this study were obtained from the National Health and Nutrition Examination Survey (NHANES) from 2007–2016. The CMI was calculated from the physical examination and laboratory test data, while the kidney stone history was obtained from the questionnaire. Multiple logistic regression analysis, smoothed curve fitting, threshold effect analysis and subgroup analysis were implemented to explore this correlation.

A total of 29,562 participants were enrolled in our study, including 5,410 (9.47%) patients who were diagnosed with kidney stones. Kidney stone incidence increased by 34% with increasing unit CMI (odds ratio (OR) = 1.34, 95% confidence interval (CI) 1.29-1.40, p < 0.0001). The prevalence of kidney stones was 2.04 times greater in the highest quartile of CMI than in the lowest quartile (OR = 2.04, 95% CI 1.82-2.30, p < 0.0001). Even after adjusting for all covariates, an increase in CMI per unit resulted in a 10% increase in kidney stone incidence (95% CI 1.04- 1.18, p=0.0018). The curve fitting results showed a positive association between CMI and kidney stones. CMI was significantly positively associated with the incidence of kidney stones in both males and females.

There was a positive correlation between CMI and the incidence of kidney stones. This indicates that CMI may serve as a valuable indicator of the risk of kidney stones.