Purpose: This study aimed to evaluate the cost-effectiveness of dabigatran and rivaroxaban compared with warfarin for the prevention of stroke in patients with atrial fibrillation (AF) in Singapore.
Methods: A Markov model was constructed to compare the lifetime costs, quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratios (ICERs) of dabigatran 110 and 150 mg, rivaroxaban 20 mg and adjusted-dose warfarin from the perspective of the Singapore healthcare system, using clinical data from published studies, utilities from a patient-reported survey and costs from hospital databases. The target population was a hypothetical cohort of 65-year-old AF patients with no contraindications to anticoagulation.
Results: In the base-case analysis, the QALYs were 8.75 with warfarin, 8.73 with dabigatran 110 mg, 8.82 with dabigatran 150 mg, and 9.33 with rivaroxaban. The costs were Singapore dollar (SG$) 34,648 for warfarin, SG$54,919 for dabigatran 110 mg, SG$50,484 for dabigatran 150 mg and SG$51,975 for rivaroxaban. The ICER of rivaroxaban versus warfarin was SG$29,697 (US$26,727) per QALY. Rivaroxaban and warfarin had extended dominance over the high-dose dabigatran. The low-dose dabigatran was dominated by warfarin. Deterministic sensitivity analyses showed that the ICER of rivaroxaban versus warfarin was sensitive to cost of rivaroxaban and utilities for rivaroxaban and warfarin. Probability sensitivity analysis demonstrated that the probability of rivaroxaban being the optimal choice was 97.8% and 99.5% at a willingness-to-pay threshold of SG$65,000 (US$58,500) and SG$130,000 (US$117,000) per QALY, respectively.
Conclusion: Rivaroxaban may be a cost-effective alternative to warfarin for the prevention of stroke in patients with AF in Singapore.