Outcomes do not differ between apixaban and warfarin plus amiodarone for AF

The risk of major bleeding and thromboembolic events is low for patients with atrial fibrillation (AF) taking amiodarone with either apixaban or warfarin, with no significant difference between the two anticoagulants, according to a retrospective observational study.

For the study, researchers obtained data from the Swedish health registers and identified patients with AF who used amiodarone concomitantly with warfarin or apixaban. Propensity score matching and Cox proportional models were used in the analyses.

The primary outcome was major bleeding resulting in hospitalization, while secondary outcomes included intracranial bleeding, gastrointestinal bleeding, and other bleeding. Ischaemic stroke/systemic embolism and all-cause/cardiovascular mortality were also assessed as exploratory outcomes.

A total of 12,103 patients met the inclusion criteria, of which 35.9 percent received apixaban and 64.1 percent received warfarin concomitantly. Patients on warfarin were more likely to be older, male, and have heart failure, myocardial infarction, and ischaemic stroke. On the other hand, patients on apixaban tended to have a history of cancer and prior intracerebral haemorrhages.

After propensity score matching, 8,686 patients remained in the study, with 4,343 each in the apixaban and warfarin groups. Rates of major bleeding over a median follow-up of 4.4 months did not significantly differ between the two groups (4.3 vs 4.5 per 100 patient-years, respectively; hazard ratio, 1.03, 95 percent confidence interval, 0.76–1.39).

The same was true for secondary outcomes including gastrointestinal bleeding and other bleeding, as well as for exploratory outcomes.