To the Editor: Dr Phung and colleagues1 presented a meta-analysis of the effectiveness of several classes of antidiabetic agents used in combination with metformin, examining the effects on glycemic control, body weight, and hypoglycemia. Sulfonylureas and thiazolidinediones are associated with significant weight gain; sulfonylureas and glinides are associated with increased risk of hypoglycemia. In contrast, DPP-4 inhibitors and GLP-1 agonists are not associated with increased hypoglycemia, and GLP-1 agonists can be associated with significant weight loss. Despite this evidence, the authors advocated use of sulfonylureas because of their lower cost and cautioned against use of DPP-4 inhibitors and GLP-1 agonists in view of what they regard as a smaller evidence base.
Rodbard HW, Jellinger PS. Adding Noninsulin Antidiabetic Drugs to Metformin Therapy for Type 2 Diabetes. JAMA. 2010;304(4):405-407. doi:10.1001/jama.2010.1021