25-hydroxyvitamin D concentrations and in vivo insulin sensitivity and β-cell function relative to insulin sensitivity in black and white youth.

摘要: OBJECTIVE To examine the relationships between plasma 25-hydroxyvitamin D [25(OH)D] and in vivo insulin sensitivity β-cell function relative to sensitivity, disposition index (DI), black white youth. RESEARCH DESIGN AND METHODS Plasma 25(OH)D concentrations were analyzed banked specimens healthy youth aged 8 18 years who had existing data on hyperinsulinemic-euglycemic hyperglycemic clamp assess secretion, measurements of body composition, abdominal visceral adipose tissue (VAT) subcutaneous (SAT). RESULTS A total 183 research volunteers (mean ± SD; age, 12.6 2.2 years; 98 white, male, 92 obese) studied. Analysis HbA 1c , fasting glucose insulin, DI across quartiles revealed no differences among whites. In blacks, observed significance higher highest quartile disappeared after adjusting for any adiposity measures (BMI or fat mass VAT SAT). The difference (9.4 1.2 vs. 5.6 0.5 mg/kg/min per μU/mL; P = 0.006) nondeficient (≥20 ng/mL) versus deficient ( CONCLUSIONS youth, bear independent relationship parameters homeostasis sensitivity. It remains be determined whether with dysglycemia are different vitamin optimization enhances function.