The relationship between the frailty index (FI) and all-cause mortality in patients with kidney stones remains unclear, and whether this relationship is mediated by the systemic Immune-Inflammation index (SII). This cohort study analyzed data from the National Health and Nutrition Examination Survey (NHANES) in the United States, spanning 2007 to 2018. Utilizing Kaplan-Meier survival curves, Cox regression analysis, restricted cubic splines (RCS), and mediation analysis, the research investigated the relationships between FI, SII, and all-cause mortality in individuals with kidney stones. During a median follow-up of 6.3 years (16695 person-years) ,356 total deaths were recorded. A cohort of 2,620 U.S. participants was enrolled from NHANES 2007-2018. Frail individuals demonstrated significantly higher all-cause mortality compared to non-frail counterparts (HR = 1.78, 95% CI: 1.56-2.02, P < 0 0.001). Among patients with kidney stones, the FI showed a positive correlation with the SII (β = 38.18, 95% CI: 10.38-65.99, P < 0.01). The SII indirectly influenced the FI and all-cause mortality in these patients, accounting for 5.6% of the mediating effect. Among U.S. adults with kidney stones, the FI is linked to a higher risk of all-cause mortality, with SII potentially serving as a biological mechanism.
Urolithiasis. 2025 Aug 31*** epublish ***
Shuangning Liu, Yu Dai, YanHu Meng, Jie Zhang, Xiaoke Sun, Yatao Jia
Department of Urology, Baoji People's Hospital, Baoji, Shaanxi Province, China., Department of Urology, Honghui hospital, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China., Department of Urology, Honghui hospital, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China. .