Abstract 16179: Cost-effectiveness of Dabigatran for Stroke Prophylaxis in Atrial Fibrillation
Introduction: The 2.3 million Americans with atrial fibrillation (AF) have a five-fold increased risk of ischemic stroke. Recent studies have investigated promising alternatives to warfarin for stroke prophylaxis in patients with AF. However, it is unknown whether these therapies are cost-effective.
Hypothesis: Based on the RE-LY (Randomized Evaluation of Long Term Anticoagulation Therapy) trial, we hypothesized that dabigatran, a new direct-thrombin inhibitor would be cost-effective in patients with atrial fibrillation who are at high risk of stroke.
Methods: We developed a semi-Markov decision model to compare the cost and quality-adjusted survival of alternative strategies for primary prophylaxis of ischemic stroke in a hypothetical cohort of 70-year-old patients with chronic AF: dabigatran, warfarin, aspirin, dual therapy with aspirin and clopidogrel, or no antithrombotic therapy. We used a cost-effectiveness threshold of $75,000/quality adjusted life-years (QALY) from a healthcare system perspective. To quantify risks of stroke and hemorrhage, we performed a meta-analysis of published atrial fibrillation trials. For all treatments, we calculated quality-adjusted survival and net cost in 2010 US dollars, over a maximum of 20 years.
Results: For patients with an average risk of hemorrhage (3.36% major bleeds/per yr of anticoagulant therapy) and a stroke rate greater than 1.5%/yr (CHADS2score > 0), warfarin was more cost-effective than aspirin. However, at a stroke rate above 5.1%/yr (CHADS2 score > 2), dabigatran 150 mg twice daily became cost effective. In patients at high risk of hemorrhage (6.6% major bleeds/yr), dabigatran 150 mg twice daily was cost-effective at a stroke rate greater than 3.0% /yr (CHADS2 score > 1). Neither dabigatran 110 mg twice daily nor dual therapy (aspirin and clopidogrel) were likely to be cost-effective.
Conclusion: Dabigatran 150 mg twice daily is likely to be cost-effective in those patients with atrial fibrillation who are at high risk of hemorrhage, high risk of stroke, or both.
- © 2010 by American Heart Association, Inc.