Apixaban vs. Warfarin and Aspirin in Atrial Fibrillation
Apixaban vs. Warfarin and Aspirin in Atrial Fibrillation
This analysis has a number of limitations. First, we were only able to assess concomitant 'low-dose' aspirin use and not other antiplatelet regimens. Secondly, the use of aspirin was neither randomized nor blinded. Although we adjusted for potential measured confounders, additional confounding almost certainly exists. Thirdly, the fact that aspirin use was not blinded may have led to differential post-randomization use of aspirin among patients assigned to apixaban and warfarin. Fourthly, as with all subgroup analyses, there may be limited power to detect an interaction between apixaban vs. warfarin and aspirin use. Fifthly, although we recorded when patients started and stopped aspirin, we did not collect the reasons for changes in aspirin therapy. Finally, these results from a randomized clinical trial may not be generalizable to other populations.
Limitations
This analysis has a number of limitations. First, we were only able to assess concomitant 'low-dose' aspirin use and not other antiplatelet regimens. Secondly, the use of aspirin was neither randomized nor blinded. Although we adjusted for potential measured confounders, additional confounding almost certainly exists. Thirdly, the fact that aspirin use was not blinded may have led to differential post-randomization use of aspirin among patients assigned to apixaban and warfarin. Fourthly, as with all subgroup analyses, there may be limited power to detect an interaction between apixaban vs. warfarin and aspirin use. Fifthly, although we recorded when patients started and stopped aspirin, we did not collect the reasons for changes in aspirin therapy. Finally, these results from a randomized clinical trial may not be generalizable to other populations.