J-shaped association between the visceral adiposity index and all-cause mortality in patients with chronic kidney disease

Abstract

ObjectiveVisceral obesity, assessed using the visceral adiposity index (VAI), is related to mortality, but studies of populations with chronic kidney disease (CKD) are scarce. The aim of this study was to evaluate the relationship between VAI and all-cause mortality among individuals with CKD. MethodsWe retrospectively explored the relationship between VAI and risk for all-cause death by analyzing the data of 4145 patients with CKD who participated in the National Health and Nutrition Examination Survey (NHANES) 2001–2006. Patients were followed until December 31, 2015. ResultsAfter an average follow-up of 134.14 mo, 1034 (24.95%) deaths were recorded. Comparison of VAI quartiles with the reference showed an unstable association of VAI with all-cause mortality after adjusting for a wide range of potential confounders in Cox regression analysis. The correlation between VAI and mortality was J-shaped after applying the penalized spline method. Before the inflection point (VAI = 68.23), higher VAI had a protective effect against mortality (hazard ratio [HR], 0.47; 95% confidence interval [CI], 0.28–0.77). However, the risk for all-cause mortality gradually increased with the VAI (HR, 1.13; 95% CI, 1.05–1.21). ConclusionVisceral obesity may influence the rate of all-cause mortality in a nonlinear manner in populations with CKD. Risk for death was higher with visceral fat deficiency than with excessive visceral fat deposition.