P4800Estimated effect of NOACs compared to Vitamin K Antagonists in real-world atrial fibrillation patients: Data from FANTASIA Registry

Abstract

Abstract Background Despite of the effectiveness and safety profile of Non-vitamin K Antagonists Oral Anticoagulants (NOACs) even in real-world (RW) Atrial Fibrillation (AF) patients, Vitamin K Antagonists (VKAs) have remained widely used in clinical practice worldwide but the comparison with acenocoumarol therapy in RW is unknown. Purpose To estimate the potential absolute benefit in clinical adverse events if the AF patients anticoagulated with VKA therapy had been treated with NOACs. Methods We analyzed anticoagulated AF patients who were prospectively recruited into the multicentre FANTASIIA registry. Patients were treated with VKAs for at least 6 months prior to inclusion. The estimation of clinical adverse events avoided was calculated applying absolute risk reductions, relative risk reductions and hazard ratios from the meta-analysis of RW use of NOACs relative to VKAs. Results We analyzed 1,470 patients under VKA therapy (mean age 74.1±9.5 years; 56.4% male). Stroke rate with acenocoumarol treatment was 0.88%/year. The estimated rates for stroke using NOACs would be 0.80%/year for Dabigatran 150 mg; 0.76%/year for Rivaroxaban and 0.74%/year for Apixaban instead of VKA. No significant differences were observed between the different NOACs and VKA in stroke rate. Major bleeding with acenocoumarol was 3.40%/year. The estimated rates for major bleeding using NOACs would be 2.75%/year for Dabigatran 150 mg; 3.37%/year for Rivaroxaban and 2.18%/year for Apixaban instead of VKA. Apixaban was the only NOAC that showed a significant estimated reduction rates (p=0.046). Finally, the all-cause mortality rate with acenocoumarol was 4.69%/year. The estimated rates of all-cause mortality using NOACs would be 3.28%/year for Dabigatran 150mg; 4.88%/year for Rivaroxaban and 2.67%/year for Apixaban. Dabigatran and Apixaban showed significant estimated reduction rates with the highest reduction with Apixaban (Table). Annual Rate reduction of adverse events Conclusion The absolute estimated effect of NOACs in the AF patients anticoagulated with VKA showed a significant reduction in adverse clinical events. Apixaban performed the highest estimated reduction in major bleeding and all-cause mortality in comparison with acenocoumarol.