Life's Essential 8 and kidney stones in US adults: mediating roles of HDL and insulin resistance

The rising incidence of kidney stones underscores the imperative to devise effective preventive measures. While a robust association between cardiovascular disease (CVD) and kidney stones exists, the current research landscape lacks investigations between cardiovascular health (CVH) and kidney stones. This study aims to explore the association between CVH, assessed by Life's Essential 8 (LE8), and kidney stones, with the role of blood lipids and insulin resistance in this relationship. The study included 19,942 adults aged ≥20 from the National Health and Nutrition Examination Survey of the US from 2007 to 2018. LE8, measuring CVH, includes four behavior and four factor metrics. Participants were categorized into high, moderate, and low CVH levels according to LE8 Scores: 80-100, 50-79, and 0-49, respectively. Kidney stones cases were identified through interviews and self-reported records. Weighted multivariate linear regressions, weighted logistic regressions, restricted cubic spline (RCS) analysis, mediation analyses, and sensitivity analyses were conducted. In the fully adjusted logistic model, 10-point increase in LE8 Score exhibited a significant 19% reduction in kidney stones prevalence (OR=0.81, 95% CI: 0.77-0.85). The RCS confirmed the nonlinear association between LE8 Score and kidney stones (P for non-linearity: 0.004). Mediation analyses showed the mediation proportions of 19.62%, 24.26%, and 27.82% for high-density lipoprotein (HDL), insulin resistance (HOMA-IR), and serum insulin, respectively. The mediation proportions of the HOMA-IR-HDL and serum insulin-HDL pathways were 6.62% and 5.96%, respectively. This study illuminates a negative association between CVH and kidney stones, providing an effective strategy for kidney stones prevention.