Are metabolic syndrome and its components in obese children influenced by the overweight status or the insulin resistance?

Introduction: The aim of this study was to determine which factors increase the risk of metabolic syndrome (MS) and its components in obese children and adolescents. Material and methods: In 78 obese children (42 girls, 36 boys), mean age 14.6 +/- 3.5 years, blood pressure, total cholesterol, triglycerides, HDL-cholesterol (HDL), insulin and glucose at fasting state as well as in OGTT were measured. Body mass index (BMI) Z-score, LDL-cholesterol, and insulin resistance indices (FIGR, R-HOMA) were calculated. Results: Metabolic syndrome was diagnosed in ten (12.8%) children. Hyperinsulinaemia was present in 42 (53.8%) subjects, increased FIGR in eight (10.3%) and increased R-HOMA in 49 (62.3%). Significant correlations between BMI Z-score >= 2.5 and MS occurrence and its components (hypertriglyceridaemia, isolated systolic and diastolic hypertension) were found. Hypertriglyceridaemia, low HDL and hypertension, as well as MS occurrence, correlated significantly with stimulated hyperinsulinaemia and increased FIGR. Risk of hypertension was increased 5.6 times by fasting hyperinsulinaemia. Stimulated hyperinsulinaemia increased the risk of hypertriglyceridaemia 3.7 times, risk of low HDL 14.4 times and risk of MS 10.3 times. These risks did not change significantly when adjusted for BMI Z-score. Conclusions: Our study results show that both BMI Z-score and OGTT stimulated hyperinsulinaemia are good predictors of MS occurrence in obese children and adolescents. The risk of dyslipidaemia and hypertension increase significantly with hyperinsulinaemia and insulin resistance, with low HDL cholesterol being the most affected. (Pol J Endocrinol 2011; 62 (2): 102-108)