Diabetes mediates the relationship between cardiometabolic index and kidney stones: a cross-sectional study

Previous studies have shown that diabetes is one of the risk factors for kidney stone formation. The Cardiometabolic Index (CMI) is a composite index used to assess an individual's cardiovascular health and metabolic status. CMI has been associated with several metabolic diseases. However, current evidence on the association between CMI and kidney stone risk is limited. The primary objective of this study was to investigate the association between CMI and kidney stones in US adults and to analyze whether diabetes mediates the association. Using data from the National Health and Nutrition Examination Survey (NHANES) conducted between 2007 and March 2018, this study examined the association between CMI and kidney stones incidence in US adults. Data were analyzed using a variety of statistical methods, including multifactorial logistic regression, subgroup analysis, restricted cubic spline curves (RCS), saturated threshold effects analysis, and mediated effects analysis. A total of 10,609 subjects were included in this study, of which 972 patients were diagnosed with kidney stones. The results of multifactorial logistic regression analysis after fully adjusting for confounding covariates showed a significant positive association between CMI and kidney stones, with an odds ratio (OR) of 1.29 and a 95% confidence interval (CI) of (1.16,1.44). In addition, there was a non-linear positive association between CMI and kidney stones. The results of mediation analysis showed that diabetes mellitus had a mediating role of 15.3% in the correlation between CMI and kidney stones. The findings of this study indicate that elevated CMI levels are associated with an increased risk of kidney stone formation, with diabetes playing a mediating role. These findings indicate that maintaining CMI within the lower range and addressing glycemic regulation is crucial for the prevention of kidney stones.