OBJECTIVES: Persistence with initial antidiabetic treatment regimens is critical for reducing the risk of adverse clinical events and costs. This study estimated the impact of persistence on clinical and cost outcomes among 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. Persistence was measured using duration of initial therapy, which was calculated as the days between the index date and end of the day’s supply prior to discontinuation [indicated by a gap in all therapy >=60 days] or last available fill date, whichever occurred first. The associations between persistence and the risk for stroke, acute myocardial infarction (AMI), and all-cause or cardiovascular disease-related hospitalizations were estimated using time-varying multivariable Cox proportional hazards models to capture the temporal relationship between discontinuation and adverse events. The impact of persistence on health care costs was estimated using generalized linear models (GLM).

RESULTS: A total of 229,485 patients met study selection criteria. Among them, 41.5% of patients discontinued their initial therapy. One month increase in the duration of initial therapy was associated with significant reductions in cardiovascular event risk (6%), all-cause hospitalization (2.4%), and cardiovascular disease-related hospitalization (1.6%). One month increase in the duration significantly decreased total healthcare costs per patient in the first year by $12.15 per month. This effect consisted of significant decreases in medical costs ($12.48), outpatient costs ($6.43), and inpatient costs ($15.88) which were partially offset by a small but non-significant increase prescription drug costs ($0.91, p=0.078).

CONCLUSIONS: Patients who are persistence on their initial antidiabetic medications enjoyed significantly reduced risks of adverse health outcomes and lower healthcare costs.