Effects of Once-Daily and Twice-Daily Dosing on Adherence With Prescribed Glipizide Oral Therapy for Type 2 Diabetes

Abstract

BACKGROUND: We evaluated differences in adherence and persistence with prescribed therapy of once-daily (OD) dosing compared with twice-daily (BID) dosing of glipizide in patients with type 2 diabetes. METHODS: The study cohort was derived from a pharmacy benefit manager claims database. Patients new to extended-release gastrointestinal therapeutic system (GITS) and immediate-release glipizide therapy were identified and followed for 1 year. Adherence indices (AIs) were calculated and persistence curves were constructed. RESULTS: Adherence indices rates were 60.5% in the GITS OD cohort and 52.0% in the BID cohort. Rates of persistence at 12 months were 44.4% in the GITS OD cohort vs 35.8% in the BID cohort. CONCLUSION: Initiation of OD pharmacotherapy results in better adherence and persistence compared with a BID regimen, despite a greater daily pill burden in the OD cohort. These data suggest that dosing frequency exerts a greater impact on patient adherence and persistence than number of tablets per dose.