The new OACs compared with warfarin
Net clinical benefit of new oral anticoagulants (dabigatran, rivaroxaban, apixaban) versus no treatment in a 'real world' atrial fibrillation population: A modelling analysis based on a nationwide cohort study.
Banerjee A, Lane DA, Torp-Pedersen C, Lip GY.
Thromb Haemost. 2012 Mar 1;107(3):584-9.
The concept of net clinical benefit is used to quantify the balance between the risk of ischemic stroke and the risk of intracranial hemorrhage during the use of oral anticoagulants in nonvalvular atrial fibrillation. It has been shown that patients with the highest risk of stroke and thromboembolism have the greatest benefit of oral anticoagulation with warfarin . For the new oral anticoagulants, the net clinical benefit in a normal population is not yet known. In this study, with data from the Danish National Patient Registry  by using a model the expected net clinical benefit of dabigatran, rivaroxaban and apixaban was calculated based on recent clinical trial results.
The new oral anticoagulants apixaban, dabigatran and rivaroxaban have a greater net clinical benefit than warfarin in patients with atrial fibrillation who are at high risk of stroke (CHA2DS2 Vasc-score of 2 or more). In patients with a lower risk of stroke but with a high risk of bleeding apixaban and dabigatran 110 mg bid had a positive net clinical benefit. In patients at average risk (CHA2DS2-Vasc = 1), the net clinical benefit is especially beneficial with apixaban and both doses of dabigatran (110 mg and 150 mg bid). When both the risk of stroke and risk of bleeding are high, all three drugs have a greater net clinical benefit than warfarin.
Clinical benefit of warfarin, dabigatran, rivaroxaban and apixaban by CHA2DS2-Vasc and HAS-BLED scores. |
HAS BLED ≤ 2
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ConclusionIn the absence of head-to-head studies, this analysis can help in selecting an oral anticoagulant for the prevention of stroke in atrial fibrillation.
Editorial comment This analysis is a unique approach to compare warfarin with new oral anticoagulants. The study does not indicate which specific drug should be used in an individual patient. Therefore long-term results are needed of each drug.
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3. Goldhaber SZ. What's the "go to" anticoagulant for stroke prevention in atrial fibrillation? Thromb Haemost 2012; 107:397-398.