Differences in the in vivo insulin secretion and sensitivity of healthy black versus white adolescents

Fourteen black and 16 white healthy adolescents underwent a 2-hour hyperglycemic clamp (12.5 mmol/L) to investigate racial differences in insulin secretion and sensitivity. First-phase and second-phase insulin concentrations were higher in black subjects than in white subjects (first phase: 944+/-110 pmol/L vs. 462+/-52 pmol/L, p=0.0003; second phase: 1050+/-146 pmol/L vs. 652+/-53 pmol/L, p=0.0012). The insulin sensitivity index was lower in black adolescents (8.21+/-1.05) compared with white adolescents (12.55+/-1.42 mu mol/kg per minute per picomole per liter, p=0.02). These findings indicate that significant differences in insulin secretion and sensitivity are detectable in healthy black versus white adolescents.