Central Adiposity and Insulin Sensitivity in Healthy African-American Children • 411

Abstract

Abdominal adiposity has been implicated as a risk factor for insulin resistance and NIDDM in adults. African-Americans (AA) are at increased risk for obesity, CVD, hypertension and NIDDM. We have shown that healthy AA children are insulin resistant and have higher insulin secretion compared with their White peers (J Pediatr 129:1996; J Clin Endocrinol Metab 82:1997). Moreover, AA children are more obese with central distribution of fat compared with their White peers. Therefore, the aim of the present investigation was to study the relationship of central obesity to insulin resistance in AA children. We studied 19 (10M, 9F) healthy AA prepubertal children, age (9.8±0.2 yrs), BMI (19.6±1.0 kg/m2). Body composition was assessed with DEXA, and abdominal adiposity by CT scan at the level of L4-5with measurements of subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT). Insulin action was assessed by a 3hr hyperinsulinemic (40mu/m2/min)-euglycemic clamp. Insulin stimulated glucose disposal (Rd) was calculated over the last 30 min of the clamp. Results: (mean ± SEM) However, in a multiple regression analysis SAT was the only significant determinant of Rd explaining 64% of its variability independent of%BF. Table