The Role of Incretins and Insulin Clearance in Postprandial Hyperinsulinemia in Black Women—The Federal Women Study

Abstract

Postprandial (PP) hyperinsulinemia may be an important cardiometabolic risk factor. Since black compared to white women have greater hyperinsulinemia after IV glucose testing, they may also be at risk for PP hyperinsulinemia. Therefore, we compared by race and menopausal status, early (0-30min) incremental area under the curve for insulin response (insulin:glucose iAUC30), intact glucagon-like peptide-1 (iGLP-1 iAUC30), glucose-dependent insulinotropic peptide (GIP iAUC30) and insulin clearance (insulin:C-peptide iAUC30) in 1federally employed women without diabetes (48% African American, 14% African immigrant, 38% white; age 44±10y (mean±SD), range 24-62y, BMI 30±5 kg/m2, range 21-45 kg/m2) who underwent a 2 hour mixed meal test (52% carbohydrate, 15% protein, 33% fat). Glucose tolerance status was determined by OGTT. No differences by race in glucose tolerance status, BMI, iGLP-1 iAUC30, or GIP iAUC30 were noted in pre- or postmenopausal women (Table). PP insulin response was higher and insulin clearance was lower in blacks (Table). Overall, PP hyperinsulinemia in pre- and post-menopausal black vs. white women was associated with lower insulin clearance, but not differences in incretin response.Table. Postprandial Glucose, Insulin and Incretin Response by Race and Menopausal Status.Pre-menopausalPostmenopausalBlack (n=49)White (n=29)P- valueBlack (n=18)White (n=12)P-valueBMI (kg/m2)30±432± 60.2029±428±50.24Prediabetes n (%)10 (20)6 (21)0.4213 (72)6 (50)0.50iGLP-1 iAUC30 (pg/mL•min)118±83108±880.3973±5989±770.82GIP iAUC30 (pg/mL•min)2704±15142961±33130.842651±13433661±46890.90Insulin response Log Insulin:Glucose iAUC304.9±6.11.9±1.3<0.013.3±1.71.0±0.4<0.01Insulin clearance Log Insulin:C-peptide iAUC30 0.93±0.031.17±0.05<0.011.13±0.081.26±0.040.28 Disclosure S.T. Chung: None. A.B. Courville: None. P.C. Aldana: None. A. Onuzuruike: None. S. Bernstein: None. M. Galvan-De La Cruz: None. L. Mabundo: None. M. Walter: None. A.E. Sumner: None.