Effectiveness And Safety Of Non-Vitamin K Antagonist Oral Anticoagulants In Atrial Fibrillation Patients With Antiphospholipid Syndrome: A Nationwide Cohort Study

Abstract Background and objectives Non-vitamin K antagonist oral anticoagulants (NOACs) are an effective and safe alternative to warfarin in atrial fibrillation (AF) patients, but there is not enough evidence that NOACs can offer sufficient protection in AF patients concomitantly diagnosed with antiphospholipid syndrome (APS). Use of rivaroxaban has been associated with an increased risk of thrombotic events compared with warfarin in results of the TRAPS trial, but the TRAPS trial is not for AF patients and included only very high-risk APS patients with triple-positive for all 3 antiphospholipid antibodies. We sought to compare thromboembolic events, bleeding, and mortality between NOAC and warfarin in patients with both AF and APS. Methods From the Korean National Health Insurance Service (NHIS) database during the period from January 1, 2011 to December 31, 2016, we identified an warfarin-treated group of patients with AF and APS (n=1,237) who were compared with a 1:1 propensity-matched NOAC treated group (n=1,237). Results After a median follow-up period of 17 months, NOAC-treated patients had lower incidence rates for ischemic stroke (5.9 and 10.5 events per 100 person-years for the NOAC and warfarin groups), major bleeding (4.1 and 8.3 events per 100 person-years, respectively), and all-cause mortality (3.4 and 15.6 events per 100 person-years, respectively) compared with warfarin in patients with AF and APS. Compared with warfarin, NOAC significantly decreased the risk of ischemic stroke (hazard ratio [HR]: 0.60, 95% confidence interval [CI]: 0.47–0.77, p<0.001), major bleeding (HR: 0.54, 95% CI: 0.41–0.72, p<0.001) and all-cause mortality (HR: 0.32, 95% CI: 0.27–0.40, p<0.001) with considering competing risk of death. Conclusions Compared with warfarin, AF patients with APS on NOACs had lower ischemic stroke, major bleeding, and all-cause mortality. Our data suggest that AF patients with APS can be safely and effectively treated with NOACs. Funding Acknowledgement Type of funding source: None