Prior studies have shown that higher drug copay may be associated with a lower medication adherence and higher healthcare resource utilization in type 2 diabetes (T2D) patients but mostly in younger commercially insured population. Hence the current study examined this association in elderly T2D patients. This retrospective database study using Medicare claims database included T2D patients on branded non-insulin anti-hyperglycemic agent (AHA) monotherapy during index period (1/1/2013-2/28/2013). Drug copay was calculated for a 30-day supply of the index AHA. Hospitalization was assessed during 10-month follow-up period. Poisson regression model was used to control for baseline characteristics to evaluate the association between copay and hospitalization. A total of 28,656 T2D elderly patients met the inclusion criteria (mean age 78 years, 53% female, and 90% white). Mean branded drug copay was of $40. Higher drug copay was associated with increase in the risk of hospitalization [(e.g., Compared to patients with <$10 drug copay, those with $60+ drug copay had 17% higher risk of hospitalization (p= 0.02)] (Table). This study suggests that higher drug copays for branded AHAs have significant impact on the risk of hospitalization in elderly patients covered under Medicare. Payers need to take into account drug copays while making formulary decisions.


L. Xu: None. M. Pawaskar: Employee; Self; Merck & Co., Inc. Y. Tang: Employee; Self; Merck & Co., Inc.. Stock/Shareholder; Self; Merck & Co., Inc.. Employee; Spouse/Partner; GlaxoSmithKline plc.. Stock/Shareholder; Spouse/Partner; GlaxoSmithKline plc.. G. Puckrein: None. S. Rajpathak: Employee; Self; Merck & Co., Inc. B.C. Stuart: Consultant; Self; Merck Sharp & Dohme Corp., Novartis Pharmaceuticals Corporation.

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