Cut-off values of waist circumference to predict metabolic syndrome in obese adolescents

Introduction: Metabolic syndrome (MetS) is a constellation of metabolic alterations related to abdominal obesity, inflammation and insulin resistance, which increase cardiovascular disease and mortality. The aims of the present study were to identify the prevalence of comorbidities and altered parameters in obese adolescents with and without MetS, and determine cut-off points of waist circumference to predict MetS. Methods: 195 obese adolescents were recruited and divided according to MetS diagnosis based on IDF criteria. Blood analyses of glucose, lipids, liver enzymes, adiponectin and leptin were measured. Insulin resistance was assessed by HOMA-IR, QUICKI and HOMA-AD. Visceral, subcutaneous and hepatic fat were ultrasonography obtained. Body composition was estimated by BOD POD system. Results: We observed a prevalence of 25% of MetS (n=50). The MetS group presented significantly higher body mass, BMI, body fat (kg), free-fat mass (kg), waist circumference, visceral fat, glucose, insulin, insulin resistance, total-cholesterol, LDL-c, VLDL-c, triglycerides, liver enzymes, blood pressure and non-alcoholic fatty liver disease (NAFLD). Significant lower QUICKI and adiponectin were noted in MetS group. MetS girls presented significantly higher leptin/adiponectin ratio compared to Non-MetS girls. Cut-off points of 111.5 cm for boys and 104.6 cm for girls of waist circumference were suggested to predict metabolic syndrome. Moreover, waist circumference was positively correlated with visceral fat and the number of metabolic syndrome parameters.