Insulin-metformin combination therapy in obese patients with type 2 diabetes

The aim of the study aus to evaluate the effects of insulin-metformin combination therapy compared to insulin monotherapy in obese, insulin-requiring patients with type 2 diabetes mellitus. Eighteen patients uncontrolled on greater than or equal to 70 U/day of insulin monotherapy were investigated in this prospective, open-label study. Patients continued their previous insulin and dietary regimens for 4 weeks, after which metformin vas added vith doses titrated to achieve a fasting plasma glucose (FPG) < 7.8 mmol/l or until the maximum daily dose was reached. Insulin-metformin combination therapy was continued for on additional 8 weeks. Insulin-metformin combination therapy resulted in a significant decrease in glycated hemoglobin values with a final mean reduction of 1.5% +/- 1.2% (p = 0.001). FPG decreased signiftcantly (p < 0.005) by week 4 of insulin-metformin therapy, but the change was not statistically significant by week 12, and daily insulin requirements were significantly reduced during combination therapy (p < 0.05), These results suggest that in obese patients with type 2 diabetes mellitus receiving greater than or equal to 70 U of daily insulin, the addition of metformin leads to improved glycemic control with lower daily doses of insulin and without adverse effects. (C) 2002 the American College of Clinical Pharmacology.