RESUMO
AIMS: To evaluate pancreatic ß-cell function (ßf) in patients with normoglycemia (NG) and normal glucose tolerance (NGT) and related risk factors. METHODS: An observational and comparative study in 527 patients with NG and NGT that were divided by quartiles of ßf according to the disposition index derived from OGTT. Anthropometrical, clinical, nutritional, and biochemical variables were measured and associated with ßf. RESULTS: Quartiles of ßf were Q1 = DI < 1.93 n = 131, Q2 = DI 1.93-2.45 n = 134, Q3 = DI 2.46-3.1 n = 133, and Q4 = DI > 3.1 n = 129. There was a progressive reduction in pancreatic ß-cell function and it is negatively correlated with age, weight, BMI, total body fat and visceral fat, waist circumference, total cholesterol, LDL, and triglycerides (p < 0.01). Glucose levels during OGTT had a negative correlation with ßf; the product of fasting glucose by 1-h glucose had the best correlation with ßf (r = 0.611, p < 0.001) and was the best predictor of ßdf (AUC 0.816, CI 95% 0.774-0.857), even better than 1-h glucose (r = 0.581, p < 0.001). Energy, fat, and carbohydrate intake were negatively correlated with ßf (p < 0.05). Glucose levels at 1-h OGTT > 110 mg/dl were positively associated with pancreatic ßdf (OR 6.85, CI 95% 3.86-12.4). In the multivariate analysis, glucose levels during OGTT, fasting insulin, and BMI were the main factors associated with ßf. CONCLUSIONS: A subgroup of patients with NG and NGT may have a loss of 40% of their ßf. Factors related to this ßdf were age, adiposity, glucose during OGTT, and the product of fasting and 1-h glucose, as well as food intake.
