Dabigatran and warfarin: comparative analysis of safety and cost

Purpose: Warfarin has long been considered the standard of care for prevention of stroke in patients with atrial fibrillation (AF) but has many disadvantages including extensive monitoring and numerous drug-drug interactions.  Dabigatran is the first oral alternative approved for prevention of stroke in non-valvular AF. It does not require routine laboratory monitoring and has minimal drug-drug interactions. One of its disadvantages, however, is its cost compared to warfarin. Additionally, post-marketing surveillance has revealed severe and fatal bleeding events with no reversal agent available. The objective of this study was to determine the frequency of bleeding events and 30-day readmissions at a large, academic medical institution and to determine the cost-effectiveness of dabigatran as compared to warfarin.

Methods: This was a retrospective study in which patients 18 years of age and older receiving dabigatran or warfarin for prevention of stroke in AF between July 1 and October 31, 2011 were identified. Patients receiving hemodialysis or with creatinine clearance less than 15 mL/min were excluded. The primary outcome of this study was the rate of bleeding and 30-day readmission related to anticoagulation complications.  A cost analysis was performed by comparing direct and indirect costs between the two drugs. P-values were calculated for baseline characteristics only.

Results: Dabigatran was associated with lower rates of bleeding and 30-day readmission than warfarin. While the direct cost of therapy for dabigatran was higher than warfarin, the cost of monitoring and readmission was lower.

Conclusion: Dabigatran appears to be a safe alternative for the prevention of stroke in patients with AF. In addition, dabigatran may be a cost-effective alternative to warfarin given the significant cost avoidance associated with lower rates of readmission. There is benefit in verifying the results of this study with a larger patient population.