Associação entre o índice de conicidade e a função renal da população brasileira: Pesquisa Nacional de Saúde, 2014-2015

Abstract

INTRODUCTION: Chronic kidney disease (CKD) is a major public health problem, frequently associated with central obesity. The Conicity Index (CI) is an anthropometric indicator that assesses abdominal fat distribution. Considering the scarcity of representative studies of the Brazilian population that have evaluated the association between the CI and renal function across all categories of glomerular filtration rate, it is relevant to investigate this relationship. OBJECTIVE: To evaluate the association between the Conicity Index and renal function in the Brazilian adult population. METHODS: Cross-sectional study conducted with data from the Brazilian National Health Survey (PNS) 2014-2015. The final sample consisted of 8,535 adults with complete data on serum creatinine and anthropometric measurements. Renal function was classified according to KDIGO based on estimated glomerular filtration rate (eGFR) using the CKD-EPI 2021 equation. The CI was dichotomized, considering the upper quartile (percentile ≥ 75) as elevated. Descriptive analyses and logistic regression (crude and adjusted models) were performed, with statistical significance set at p < 0.05. RESULTS: The prevalence of eGFR < 60 mL/min/1.73 m² was 5.3%. In the crude analysis, the upper quartile of the CI was significantly associated with stages G3a (OR = 3.16), G3b (OR = 4.91), and G4 (OR = 8.53). After adjustment for sociodemographic, clinical, and behavioral factors, the association lost statistical significance. CONCLUSION: The association between the Conicity Index and renal function did not persist after adjustments, indicating a strong influence of clinical and sociodemographic factors. Longitudinal studies are recommended to better clarify this relationship.