Cutoff Point of TyG Index for Metabolic Syndrome in Brazilian Farmers

Abstract

\n \n \n The determination of Insulin Resistance (IR) requires sophisticated and costly methods, for this reason the TyG Index was proposed. However, there are still no studies in Brazil using Metabolic Syndrome (MetS) as a predictor of IR. Thus, the aim of this study was to determine the cutoff point for TyG as one of the indirect indices for MetS in a rural Brazilian population.\n \n \n \n Cross-sectional observational epidemiological study conducted in a rural municipality in Brazil. The study population were 790 adult family farmers. The TyG index was calculated: Ln [fasting triglycerides (mg/dL) x fasting glycemia (mg/dL)]/2, and MetS was defined using the NCEP-ATPIII and IDF criteria. To describe the study variables, measures of central tendency and dispersion measures were used. For association analysis, the Mann-Whitney U test was used and the comparison between means was made using the Kruskal-Wallis test. For correlations, Spearman s correlation test was used. The cutoff values of TyG Index for MetS were obtained using the Receiver Operating Characteristic (ROC) curve analysis with the area under the curve (AUC) and the Youden Index.\n \n \n \n The median TyG values were higher among individuals diagnosed with MetS (P\xa0<\xa00.001), and increased according to the aggregation of the components of MetS. All MetS components were correlated with TyG (P\xa0<\xa00.001). The AUC for NCEP was 0.873 (0.848–0.896; P\xa0<\xa00.001), with Youden s cutoff point of Ln 4.52 (sensitivity: 84.30%; specificity: 75.75%). The AUC for IDF was 0.867 (0.842–0.890; P\xa0<\xa00.001), with Youden s cutoff point of Ln 4.55 (sensitivity: 80.0%; specificity: 79.82%). A cutoff point of Ln 4.52 was defined.\n \n \n \n The TyG Index is a reliable marker for identifying insulin-resistant individuals, and correlates with the metabolic changes present in MetS. A cutoff point of Ln 4,52 has good sensitivity and specificity in both diagnostic criteria of MetS, being useful both in clinical practice and epidemiological studies, and can represent an important tool for the creation of protocols for promotion, protection and recovery health of rural populations.\n \n \n \n Research Program of the Unified Health System (PPSUS), through the notice FAPES/CNPq/Decit-SCTIE-MS/SESA No. 05/2015 – PPSUS.\n