ZJU index and prevalence of kidney stones in US adults: evidence for a threshold association from NHANES 2007-2018.

BACKGROUND

The Zhejiang University (ZJU) index is a novel composite metric that integrates fasting plasma glucose (FPG), body mass index (BMI), triglycerides (TG), and liver function markers including alanine aminotransferase (ALT) and aspartate aminotransferase (AST), reflecting lipid metabolism disturbances and insulin resistance (IR) development. This research aims to clarify the potential correlation between ZJU and kidney stones.

METHODS

This research analyzed data from the 2007-2018 National Health and Nutrition Examination Survey (NHANES) in a cross-sectional study. Weighted logistic regression and nonlinear regression analysis were applied to investigate the correlation between the ZJU index and kidney stones. The robustness of the results was further examined through subgroup analyses. Predictive performance was assessed through receiver operating characteristic (ROC) curves.

RESULTS

Among 13,963 participants aged 20 and above, 9.19% were diagnosed with kidney stones. In the fully adjusted multivariable model, an elevated ZJU index was significantly associated with a greater likelihood of kidney stone [odds ratio (OR) =1.53; 95% confidential interval (CI): 1.38-1.70, P<0.0001]. Subgroup analyses and nonlinear regression analysis are used to validate this association further. Finally, the ROC curve analysis demonstrated that the ZJU index outperformed BMI, triglyceride-glucose (TyG), and non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) in estimating the risk of kidney stones.

CONCLUSIONS

An elevated ZJU index was clearly related to a higher prevalence of kidney stones. This suggests that the ZJU may be a valuable biomarker for identifying individuals at increased risk of kidney stones.