Evaluation of Dipeptidyl Peptidase-4 Inhibitors versus Thiazolidinediones or Insulin in Patients with Type 2 Diabetes Uncontrolled with Metformin and a Sulfonylurea in a Real-World Setting.

Abstract

Guidelines do not make clear recommendations for third add-on agents to metformin plus a sulfonylurea. This study compared the effectiveness and safety of dipeptidyl peptidase-4 inhibitors (DPP4is) to thiazolidinedione (TZD) or insulin as a third add-on agent to metformin plus a sulfonylurea in an integrated health care setting. This retrospective database cohort study included adults with type 2 diabetes not at goal hemoglobin A1C (HbA1C) who initiated DPP4i, TZD, or insulin as a third add-on agent to metformin plus a sulfonylurea from January 2006 to June 2016. Primary outcomes were the proportion of patients who achieved goal HbA1C after starting the third add-on agent and change in HbA1C. Subgroup analysis was performed for patients with baseline HbA1C greater than 9%. In this study, 2080 patients started on a DPP4i were matched to 8320 patients started on TZD and to 8320 patients taking insulin. A significantly higher percentage of patients taking TZD reached goal HbA1C (31.0% versus 23.6%; p < 0.05) and had a significantly larger HbA1C reduction (-0.94% ± 1.34% versus -0.79% ± 1.23%; p < 0.01) compared to patients taking a DPP4i. No difference in the percentage of patients meeting goal HbA1C nor in change in HbA1C was demonstrated between insulin versus DPP4i regimens. For patients with baseline HbA1C greater than 9%, insulin or TZD resulted in a significantly higher proportion of patients achieving goal HbA1C compared to DPP4i (17.3% and 19.0% versus 12.4%, respectively; p < 0.01). TZD was more effective than DPP4i but DPP4i was as effective as insulin as a third add-on agent in the overall study population. Insulin was more effective than DPP4i only in the subgroup analysis of patients with baseline HbA1C greater than 9%.