Résumé
Backgrounds: There is a high prevalence of obesity and hyperinsulinism among Chilean prepuberal children. Aim: To evaluate insulin sensitivity (IS) using fasting insulin, the Homeostasis Model Assessment (HOMA) and quantitative insulin-sensitivity check index (QUICKI) in Chilean children. Material and Methods: Body mass index (BMI), total body fat percentage ( percentTBF) using the sum of 4 skin folds, abdominal obesity determined through waist circumference (WC), pubertal maturation using five Tanner stages, fasting glucose (Glu) and insulin (Ins), were measured in 354 children aged 6 to 15 years (173 males). IS was evaluated using HOMA and QUICKI. Results: IS was strongly associated with percentTBF and WC. Ins, HOMA and QUICKI were significantly correlated with BMI (r =0.412; 0.405 y -0.442, respectively), percentTBF (r =0.370; 0.367 y -0.394, respectively), and WC (r =0.452; 0.446 y -0.481, respectively). Ins and HOMA increased and QUICKI decreased significantly (p <0.0001) with age. Children in a similar Tanner stage did not have differences in Ins, HOMA and QUICKI. No differences in Ins, HOMA and QUICKI were observed between children in Tanner stages 1 and 2. However, children in Tanner stages 1 and 2, had significantly lower Ins and HOMA and higher QUICKI than those in Tanner 3 to 5 stages. The highest Ins quartile for Tanner stages 1 and 2 was 10.0 æUI/dl; for Tanner stages 3 to five, the figure was 15.6 æUI/dl. Conclusions: These results confirm the relationship of IS with BMI, percentTBF, WC and pubertal maturation. IS decreases significantly and fasting Ins levels increase approximately 50 percent with puberty. This fact must be considered for the diagnosis of hyperinsulinism and insulin resistance in children.