Obesity and metabolic syndrome in 7-9 years-old Portuguese schoolchildren

Background: Body fat is related to changes in lipid profile, blood pressure and metabolism of insulin and glucose,known as the metabolic syndrome (MS). The aim of this study was to estimate the prevalence of metabolic syndrome(MS) and its components among overweight and obese Portuguese schoolchildren, and to identify associated clinicaland biochemical characteristics.Methods: A total of 82 children (14 overweight and 68 obese; 40 boys and 42 girls) aged 7-9 years, underwentanthropometric measurements. A blood sample was obtained to assess biochemical parameters. Insulin resistance (IR)was determined by the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR). MS was defined by theNational Cholesterol Education Program Adult Treatment Panel III criteria modified by Cook.Results: The prevalence of MS was 15.8%. Abdominal obesity was present in all children. Frequency of elevated bloodpressure, low HDL-cholesterol and elevated triglyceride concentrations were 62.6%, 13.4% and 11.0%, respectively.None of the children presented impaired fasting glucose, however hyperinsulinemia (7.3%) and IR (8.5%) wereobserved. The number of components of MS was higher in children with higher z-BMI (ρ = 0.411; p < 0.001). MS wasassociated with higher leptin concentrations. No association was found with adiponectin or ghrelin levels. Leptincorrelated positively with obesity, glucose metabolism, lipid profile, hepatic function and C-reactive protein, andnegatively with HDL and Apolipoprotein A-I/B ratio.Conclusions: This study shows a significant prevalence of MS among obese schoolchildren. Abdominal obesity andelevated blood pressure were the most frequent components of this syndrome. Dyslipidemia, IR and high levels ofleptin were also associated with MS in this young group