OBJECTIVES: Lack of medication persistence with antidiabetic drug therapy increases risk of diabetes complications and hospitalizations. This study assessed the impact of type of initial antidiabetic medications, demographic and clinical factors on persistence among adult patients with type 2 diabetes (T2D).

METHODS: We identified adults aged over 26 years with T2D who initiated treatment with oral antidiabetic therapy using Optum’s De-identified Clinformatics® Data Mart database [2007-2018]. Patients were required to have continuous enrollment >=12 months before and >=12 months after the index prescription. The initial treatment regimen was defined as all medications used in the 6-week period following the first antidiabetic medication to capture adjustments that are common in real world practice. Persistence was measured using time to discontinuation [time to a gap in all therapy >=60 days]. The primary independent variable of interest was the medication class(es) used as initial therapy. Demographic and clinical characteristics included age, gender, health insurance, prior healthcare utilization, diagnostic mix and prior use of non-diabetic medications. The association between initial therapy and patients’ characteristics and the likelihood of discontinuation was estimated using Cox proportional hazards models.

RESULTS: A total of 229,485 patients meeting study criteria were identified. Patients initiating treatment using sulfonylurea monotherapy, thiazolidinedione (TZD) monotherapy, or combination therapy were 5.2%, 28.7%, and 19.9% significantly less likely to discontinue initial therapy than patients initiating treatment on metformin monotherapy. Patients who were older, had lower prior medical costs, and higher prior drug costs were significantly less likely to discontinue their initial therapy. Patients who received anti-infectives, autonomic drugs, central nervous agents, muscle relaxants, and respiratory agents were significantly more likely to discontinue while patients who received cardiovascular drugs and electrolytic agents were significantly less likely to discontinue.

CONCLUSIONS: Patients initiating sulfonylurea, TZD, or combination therapy were significantly less likely to discontinue their initial treatment regimen.