Optimal candidates for the switch from glimepiride to sitagliptin to reduce hypoglycemia in patients with type 2 diabetes mellitus

Background: Sitagliptin is a novel antidiabetic agent with a low risk for hypoglycemia. We investigated the efficacy and safety of sitagliptin when patients switched from a sulfonylurea to sitagliptin and identified good candidates for the switch. Methods: Sixty-one patients with type 2 diabetes switched from glimepiride with metformin to sitagliptin with metformin due to clinical hypoglycemia. Serum glycated hemoglobin (HbA1c), fasting plasma glucose (FPG), and 2-hour postprandial plasma glucose (2h-PPG) before and 12 and 24 weeks after the drug switch were checked. Results: HbA1c and FPG levels did not change 12 or 24 weeks after the switch; however, the 2h-PPG level decreased from 218.0±67.5 mg/dL at baseline to 197.1±69.9 mg/dL at 12 weeks and 192.3±67.4 mg/dL at 24 weeks after switching drugs (P=0.045, P=0.018, respectively). All but one patient no longer experienced hypoglycemia after discontinuing glimepiride. In a multivariate logistic regression analysis, a high homeostasis model assessment of insulin resistance and low baseline HbA1c level were independent predictors of an HbA1c ≤7% after switching to sitagliptin. Conclusion: Glycemic control was not aggravated in patients 24 weeks after the drug switch, and symptomatic hypoglycemia decreased significantly. Patients with dominant insulin resistance may be good candidates for switching from a sulfonylurea to sitagliptin to reduce hypoglycemia.