Given their ease of use, reliable clinical profiles, lack of drug-drug interactions, and safety and efficacy record, the novel oral anticoagulants (NOACs) are quickly becoming mainstream for practitioners when considering oral anticoagulation for a patient with atrial fibrillation (AF). Yet NOACS are not without some controversy. Results of randomized trials of patients with nonvalvular AF (who have higher risk of MI) showed a nonsignificant reduction in the annual risk of MI when patients received either apixaban (ARISTOTLE) or rivaroxaban (ROCKET-AF) and the RE-LY trial raised some concerns about MI risk with dabigatran. The evidence is no more conclusive for vitamin K antagonists (VKA) and risk of MI.
A recent paper published in JACC set out to resolve the conflicting evidence. Lee et al reported on their study of a Danish registry that analyzed “real world” data (including elderly and high-risk patients) on treatment-specific risk of MI in patients not previously treated with oral anticoagulation. There were 31,379 patients, mean age 74 years, 47% women. Approximately one-quarter each were treated with VKA, apixaban, dabigatran, and rivaroxaban. There were some differences among the groups:
- VKA group had highest proportion of men (59%)
- Apixaban group was the oldest (median age 76 years)
- Apixaban and rivaroxaban groups had the highest proportion of CHA2DS2-Vasc score ≥3.
There was a 28% discontinuation rate during follow-up.