Abstract
Dabigatran has been shown to be superior to warfarin for stroke prevention in nonvalvular atrial fibrillation (NVAF) but with higher out-of-pocket costs for patients. Although dabigatran has been shown to be cost effective from a societal perspective, cost implications for individual patients and insurers are not well described. We aimed to assess cost perspectives of each payer (Medicare and patient) in relation to administration, monitoring, and adverse outcomes for dabigatran and warfarin in patients with and without prescription drug coverage. Using a Markov model, we performed a decision analysis comparing 2 treatment strategies (dose-adjusted warfarin and dabigatran 150 mg twice daily) in patients 65 years old with NVAF, CHADS2 scores ≥ 1, and Medicare insurance. Patients have a quality-adjusted life expectancy of 8.998 quality-adjusted life years with warfarin and 9.39 quality-adjusted life years with dabigatran 150 mg twice daily. From Medicare's perspective, the incremental cost-effectiveness ratio comparing dabigatran with warfarin was $35,311 for patients with Part D coverage and cost saving for patients without coverage. From the patient's perspective, the incremental cost-effectiveness ratio comparing dabigatran with warfarin was cost saving for patients with Part D coverage and $63,884 for those without coverage. In patients ≥ 65 years with NVAF and prescription insurance coverage, dabigatran 150 mg twice daily is both cost effective (Medicare's perspective) and cost saving (patient perspective) compared with warfarin, at a willingness-to-pay threshold of $100,000. However, patients without prescription drug coverage have a high out-of-pocket cost burden with dabigatran therapy, leading to a reduction in its cost-effectiveness compared with warfarin therapy. In conclusion, this Markov model suggests that Medicare Part D coverage influences the cost-effectiveness of dabigatran 150 mg daily compared with dose-adjusted warfarin from multiple payer perspectives.