Association of Body Mass Index and Insulin Resistance with Metabolic Syndrome in Brazilian Children

Background: The clustering of cardiovascular risk factors called metabolic syndrome occurs in both children and adults. Insulin resistance and obesity are usual parts of the picture, but their joint effects on the onset of the syndrome remains somewhat debatable. Objective: : The purpose of the current study was to examine the relationship of the body mass index (BMI) and insulin resistance with the metabolic syndrome (MS) in children. Methods: We studied 109 children, 55 boys and 54 girls, between 7 and 11 years of age (55 obese, 23 overweight and 31 controls). The weight status of each child was defined based on BMI/age ratio. Blood glucose, HDL, triglycerides and insulin were measured using fasting samples. Blood pressure was measured twice. The metabolic syndrome was defined according to the NCEP ATP III criteria. Results: The diagnosis of the MS was only found in obese children. The greater frequency of MS and of many of its components have been found in the children classified above the third quartile of the HOMA index, which is consistent with an association between insulin resistance and cardiovascular risk factors among the Brazilian children. Conclusion: The present study shows that obesity and insulin resistance are likely to play a role in the development of cardiovascular risk factors in children since the prevalence of classic risk factors was higher in the upper BMI and HOMA percentiles. (Arq Bras Cardiol 2009; 93(2): 139-144)