Relationship between beta-cell responsiveness and fasting plasma glucose in Caucasian subjects with newly presenting type 2 diabetes.

AIMS : beta-cell responsiveness was related to fasting plasma glucose to gain further understanding of pathophysiology of Type 2 diabetes. METHODS : An insulin secretion model gave fasting beta-cell responsiveness M0 (ability of fasting glucose to stimulate beta-cell) and postprandial beta-cell responsiveness MI (ability of postprandial glucose to stimulate beta-cell) by analysing glucose and C-peptide time-concentration curves sampled every 10-30 min over 240 min during a meal tolerance test (MTT; 75 g CHO, 500 kcal). Caucasian subjects with newly presenting Type 2 diabetes according to WHO criteria (N = 83, male/female: 65 : 18, age: 54 +/- 10 years, body mass index (BMI): 30.9 +/- 5.2 kg/m2, fasting plasma glucose (FPG): 11.0 +/- 3.2 mmol/L; mean +/- SD) and Caucasian healthy subjects (N = 54, m/f: 21 : 33, age: 48 +/- 9 years, BMI: 26.1 +/- 3.7 kg/m2, FPG: 5.1 +/- 0.4 mmol/L) were studied. RESULTS : A continuum inverse relationship between MI and FPG was observed. In the diabetes group, MI was closely related to FPG (rs = -0.74, P < 0.0001) and explained 60% intersubject FPG variability with the use of an exponential regression model. CONCLUSIONS : In newly presenting Type 2 diabetes in Caucasian subjects a close inverse association exists between postprandial beta-cell responsiveness and FPG.