Previous randomized controlled trials (RCTs) have reported conflicting results for the efficacy of sitagliptin and sulfonylurea therapy in patients with type 2 diabetes mellitus showing inadequate glycemic control with metformin monotherapy. To clarify these findings, a meta-analysis was conducted of the outcomes of all published RCTs comparing sitagliptin with sulfonylureas in the treatment of type 2 diabetes mellitus. Standard medical databases were searched to identify relevant English- and Chinese-language RCTs. RCT results were compared regarding the mean change in glycated hemoglobin (HbA1c) level; the proportion achieving <7% HbAlc; and a change in body weight. No significant differences were found between the metformin plus sitagliptin and metformin plus sulfonylurea groups regarding HbAlc or the proportion achieving <7% HbAlc, while the metformin plus sitagliptin group experienced fewer hypoglycemic events (P<0.00001) and a greater reduction in body weight (P<0.00001). Metformin plus sitagliptin therapy may decrease HbAlc values in patients with type 2 diabetes mellitus who are not achieving their glycemic targets with metformin monotherapy in a manner similar to metformin plus sulfonylurea therapy, whilst posing a lower risk of hypoglycemia, and yielding a more beneficial effect on body weight.
Keywords: diabetes mellitus; metformin; sitagliptin.