title: Different effect of acute and chronic oral metformin administration on glucose and insulin response to bread and to pasta in non-insulin dependent diabetic patients.
abstract: The aim of the study was to evaluate whether acute and chronic metformin administration may influence differently the glycaemic and insulin response to foods with high and low glycaemic index (bread and pasta) in twelve non-insulin dependent diabetic (NIDDM) patients. Thirty minutes after a random oral administration of either a placebo or a single 850 mg metformin dose, glycaemic and insulin responses to 90 g white bread or 68 g pasta (corresponding to 50 g carbohydrates) were evaluated within 4 h. All the patients were subsequently treated with metformin (850 mg twice a day) for a month and then glycaemic and insulin responses were evaluated again. The acute administration of metformin lowered glycaemic response to bread at 60 and 90 min (P < 0.02 and P < 0.05, respectively) but not to pasta, without affecting insulin response. Chronic metformin treatment significantly lowered glycaemic and insulin response to both bread and pasta. In conclusion, an acute antihyperglycaemic effect of metformin was demonstrable only when a food with high glycaemic index, such as bread, was eaten. On the contrary, the effect of chronic treatment was always present, independent from the glycaemic index of foods, together with a reduction in insulin response, indicating an enhanced sensitivity to endogenous insulin.
authors.affiliation: Department of Internal Medicine, Endocrinology and Metabolic Diseases, University of Catania, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Lunetta
authors.forename: M
authors.initials: M
authors.lastname: DiMauro
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000032:analysis / Q000187:drug effects*; D001939:Bread; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy*; D005260:Female; D005502:Food; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D007328:Insulin / Q000097:blood*; D008297:Male; D008687:Metformin / Q000627:therapeutic use*
chemical_list: D001786:Blood Glucose; D007004:Hypoglycemic Agents; D007328:Insulin; D008687:Metformin