The world of anticoagulation turned upside-down with dabigatran, and continued with the Factor Xa inhibitors: rivaroxaban, apixaban, and edoxaban. While RE-LY and its ilk showed, in the settings of controlled clinical trials, that these new agents were potentially superior, or at least non-inferior, to warfarin – which is best? Do we have any idea?
Unfortunately, such comparative effectiveness work is sadly lacking, and we are forced to try and glean safety data indirectly following approval. This study pools Medicare beneficiaries using the new agents for stroke prevention in the setting of nonvalvular atrial fibrillation, and attempts to observe “real world” outcomes.
The winner on stroke prevention: rivaroxaban, by a hair. The winner on bleeding: dabigatran, by a long shot, both intra-cranial and extra-cranial. Overall mortality, then, slightly favored dabigatran.
These data are retrospective and tortured by statistical matching methods, so their reliability is hardly bulletproof. What this does raise are more questions about the appropriate usage of these new agents – and further emphasizes the importance of prospectively performed patient-centered effectiveness research.
“Stroke, Bleeding, and Mortality Risks in Elderly Medicare Beneficiaries Treated With Dabigatran or Rivaroxaban for Nonvalvular Atrial Fibrillation”
http://archinte.jamanetwork.com/article.aspx?articleid=2560376
Assuming the published studies may be trusted at face value (wink , wink), this Canadian guy has devised a very nice calcualtor for Afib prevention.
It computes the known scores for benefit AND harm. Usually , harms are left
For small embolic risks you realise choice requires knowing both sides.
It also gives the probablility of bleeds and stroke with no anticaoagulant and all molecules tested
My preferred calculator.
http://www.sparctool.com/