Apixaban a better anticoagulant compared to Rivaroxaban in AF, finds JAMA study

Atrial fibrillation incidence has increased the aging of populations worldwide, and increased survival with chronic diseases, the incidence and prevalence of atrial fibrillation (AF) are rising, justifying the term global epidemic.

Rivaroxaban and rivaroxaban are comparitively the most frequently prescribed oral anticoagulants for ischemic stroke prevention in patients with atrial fibrillation, their effectiveness and safety is uncertain.

A retrospective study by Dr Ray A Wayne PhD and team has revealed that amidst Medicare beneficiaries 65 years or older patients with atrial fibrillation, rivaroxaban showed higher adverse events compared with apixaban. Further it was significantly associated with increased risk of major ischemic or hemorrhagic events.

The findings of the study are published in JAMA Network.

The objective of the study was to compare major ischemic and hemorrhagic outcomes in patients with atrial fibrillation treated with rivaroxaban or apixaban.

The study was a retrospective cohort study using computerized enrollment and claims files for US Medicare beneficiaries 65 years or older. A total of 581 451 patients with atrial fibrillation began rivaroxaban or apixaban treatment and were followed up for 4 years, The primary outcome was a composite of major ischemic (stroke/systemic embolism) and hemorrhagic (intracerebral hemorrhage/other intracranial bleeding/fatal extracranial bleeding) events. Secondary outcomes were nonfatal extracranial bleeding and total mortality (fatal ischemic/hemorrhagic event or other death during follow-up). Rates, hazard ratios (HRs), and rate differences (RDs) were adjusted for baseline differences in comorbidity with inverse probability of treatment weighting.

The results of the study were found to be

• Study patients aged 77.0 years; 291966 women; 134393 receiving reduced dose had 474605 person-years of follow-up.

• The adjusted primary outcome rate for rivaroxaban was 16.1 per 1000 person-years vs 13.4 per 1000 person-years for apixaban (RD, 2.7).

• The rivaroxaban group had increased risk for both major ischemic events ( RD, 1.1 ) and hemorrhagic events ( RD, 1.6), including fatal extracranial bleeding ( RD, 0.4).

• Patients receiving rivaroxaban had increased risk of nonfatal extracranial bleeding (RD, 21.1), fatal ischemic/hemorrhagic events (RD, 1.2), and total mortality ( RD, 3.1).

• The risk of the primary outcome was increased for rivaroxaban in both those receiving the reduced dose (RD, 6.4)and the standard dose (RD, 1.8) groups.

Wayne and team concluded that "Among Medicare beneficiaries 65 years or older with atrial fibrillation, treatment with rivaroxaban compared with apixaban was associated with a significantly increased risk of major ischemic or hemorrhagic events."

Reference: doi:10.1001/jama.2021.21222