The effects of metformin plus sulfonylurea therapy on clinical features of the metabolic syndrome

Introduction. Insulin resistance is a well-known leading factor in the development of metabolic syndrome. The aim of this study was to evaluate metabolic effects of metformin added to sulfonylurea in unsuccessfully treated type 2 diabetic patients with metabolic syndrome. Material and methods. A group of thirty subjects, with type 2 diabetes, secondary sulfonylurea failure and metabolic syndrome were administered the combined therapy of sulfonylurea plus metformin for six months. Metformin 2000 mg/d was added to previously used sulfonylurea agent in maximum daily dose. Antihypertensive and hypolipemic therapy was not changed. The following parameters were assessed at the beginning and after six months of therapy: glycemic control, body mass index, waist circumference, blood pressure, triglycerides, total cholesterol and its fractions, homeostatic models for evaluation of insulin resistance and secretion (HOMA R, HOMA B) and C- peptide. Results. Glycemic control was significantly improved after six months of the combined therapy: (fasting 7.89 vs. 10.61 mmol/l. p<0.01; postprandial 11.12 vs. 12.61 mmol/l. p<0.01, p<0.01; glycosylated hemoglobin 6.81 vs. 8.83%. p<0.01). the body mass index and waist circumference were significantly lower (26.7 vs. 27.8 kg/m2, p<0.01 and 99.7 vs. 101.4 cm for men, p<0.01; 87.2 vs. 88.5 for women, p<0.01). Fasting plasma triglycerides decreased from 3.37 to 2.45 mmol/l (p<0.001) and HOMA R from 7.04 to 5.23 (p<0.001). No treatment effects were observed on blood pressure, cholesterol, and residual insulin secretion. Conclusion. Administration of metformin in type 2 diabetes with metabolic syndrome decreased cardiovascular risk factors by reducing glycemia, triglycerides, BMI, central obesity and insulin resistance.