Abstract 18530: Patients with Type 2 Diabetes Have Worse Persistency with Statin Therapy than with Oral Antihyperglycemic Regimen

Abstract

Introduction: Based on treatment guidelines, statin therapy is recommended for almost all patients (pts) with type 2 diabetes (T2DM) to reduce their elevated cardiovascular (CV) risk. Persistence with both oral antihyperglycemic drugs (OAD) and statin is critical to realize the long-term clinical benefits on glycemic control and CV outcomes. The purpose of this study was to compare the persistency between statin and OAD in pts with T2DM who received concomitant OAD and statin therapies.

Methods: The study used a large US commercial claim database (MarketScan). Patients with T2DM, who were ≥18 yrs, and dispensed both a statin and an OAD prescription on the same date (with first date of such dispensing as the index date) in 2006 were included in the study. All selected pts' medical records were evaluated for 1 yr prior to (baseline) and for 2 yrs after (follow-up) the index date. Statin therapy and OAD regimen were assessed collectively as separate entities. The 2-yr medication possession ratio (MPR) was compared between statin and OAD. For a non-persistent event, treatment discontinuation was defined by a gap >30 days between the last date of supply from previous dispensing and the subsequent refill. Follow-up was censored at the end of 2 yrs. The likelihood of discontinuation of statin vs. OAD was estimated from fitting a robust Cox proportional hazards regression model, adjusted for pt characteristics and co-morbidities at baseline.

Results: Of the 50,092 pts meeting inclusion criteria, mean (SD) age was 62 (12) yrs, 54% were male, 23% had existing CV conditions, and 14% had diabetes-related complications at baseline. The 2-yr MPR was 70% for statin and 78% for OAD regimen. A lower proportion of patients stayed on statin at the end of 2-yr follow-up than OAD (28% vs. 42%). The median time to discontinuation of statin was shorter compared with OAD therapy (285 vs. 498 days, p<0.001). Pts with T2DM were 47% more likely to discontinue statin therapy than OAD (adjusted hazards ratio: 1.47 [95% CI 1.45, 1.50]).

Conclusion: This study showed that persistency with statin significantly lagged behind OAD in pts with T2DM who were treated with statin and OAD simultaneously. Integrative approaches for minimizing this gap might potentially reduce CV risks in this population.