Abstract
OBJECTIVE: To investigate the association between atherogenic index of plasma (AIP) and risk of incident kidney stones. METHODS: A nested case-control study was conducted using data from the Shanghai Kidney Stone Cohort from December 2018 to February 2023. Kidney stones were ascertained by ultrasound. Propensity score matching selected 2,550 patients with incident kidney stones and 5,100 controls from a total of 64,121 adults. Baseline fasting plasma samples were collected to measure the AIP, defined as the logarithm of the ratio triglycerides to high-density lipoprotein cholesterol. A multivariable conditional logistic regression model and restricted cubic spline were applied to examine the association between the AIP and the risk of incident kidney stones. RESULTS: The baseline AIP values of the incident kidney stone patients and controls were 0.98 (0.67) and 0.91 (0.65), respectively. Patients with incident kidney stones had much higher baseline AIP levels than controls (p < 0.001). Participants in the highest AIP quartile had a 29% greater risk of developing kidney stones. Moreover, each increase in the standard deviation of the AIP was associated with a 10% greater risk of nephrolithiasis. A restricted cubic spline showed a significant positive and linear correlation between the AIP and the risk of developing kidney stones (P-overall = 0.040, P-nonlinear = 0.923). These findings remained robust in sensitivity analyses. CONCLUSIONS: A higher AIP is associated with a greater risk of incident kidney stones.