Influence of metabolic control on splanchnic glucose uptake, insulin sensitivity, and the time required for glucose absorption in patients with type 1 diabetes

Abstract

OBJECTIVE - The relationship between splanchnic glucose uptake (SGU) after oral glucose administration and metabolic control in type 1 diabetic patients is controversial. We estimated SGU as well as peripheral glucose uptake and the time required for glucose absorption by a validated method, the oral glucose (OG) clamp, in type 1 diabetic patients with different levels of long-term glycemic control. RESEARCH DESIGN AND METHODS - An OG clamp (which combines a hyperinsulinemic clamp [120 mU·m-2·min-1] with an OR load [75 g] during steady-state glucose uptake) was performed in eight type 1 diabetic patients with good metabolic control (DG) (HbA 1c 6.1 ± 0.2%, BMI 23.1 ± 0.7 kg/m2), eight type 1 diabetic patients with poor metabolic control (DP) (HbA1c 8.5 ± 0.3%, BMI 25.4 ± 1.4 kg/m2), and eight healthy matched control subjects (C) (HbA1c 5.1 ± 0.1%, BMI 25 ± 1.3 kg/m2) to determine SGU, glucose uptake, and glucose absorption. RESULTS - Glucose uptake calculated from 120 to 180 min during the clamp was 9.13 ± 0.55 mg·kg-1·min-1 in C, 8.18 ± 0.71 mg·kg-1·min-1 in DG, and 7.42 ± 0.96 mg·kg-1 ·min-1 in DP (NS). Glucose absorption was 140 ± 6 min in C, 156 ± 4 min in DG, and 143 ± 7 min in DP (NS). The respective calculated SGU was 14.5 ± 5.6% in C, 17.8 ± 3.1% in DG, and 18.8 ± 4.2% in DP (NS) and did not correlate with HbA1c values. CONCLUSIONS - Peripheral glucose uptake, SGU after oral glucose administration, and the glucose absorption time were not different in type 1 diabetic patients independent of glycemic control when compared with healthy subjects.