Comparing Oral Anticoagulants for Thromboembolic Prevention in Nonvalvular Atrial Fibrillation: A Systematic Review of Randomised Controlled Trials


  • Ellie Hawkins NAPSA



DOAC, Warfarin, Atrial fibrillation, Stroke prevention, Thromboembolism, undergraduate research , pharmacy, pharmacy research, student-led journal, systematic review


Background: Atrial fibrillation increases a person’s risk of stroke by inducing a procoagulant environment within the atrium. This risk can be decreased through appropriate anticoagulation. Direct-oral anticoagulants (DOACs) and warfarin (vitamin K antagonist) are indicated to reduce thromboembolic outcomes; however, each anticoagulant is associated with different risks that need to be considered before prescribing.

Aim: To compare the safety and efficacy of DOACs and warfarin for stroke prevention in nonvalvular atrial fibrillation using literature from online databases and registries.
Data Sources: Online databases and registries were searched to identify studies from PubMed (MEDLINE), Cochrane Library, Google Scholar, ANZCTR, ICTRP and Registry.

Study Selection: Preferred Reporting of Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used to systematically screen for, and analyse the included studies which were selected based on strict inclusion criteria. The risk of bias was assessed for each study using the Cochrane Handbook for Systematic Reviews of Interventions and the RoB 2 tool. Four studies were included in this review. All DOACs showed non-inferior efficacy to warfarin, except for apixaban (p=0.01) and dabigatran 150 mg (p<0.001), which showed superior efficacy compared to warfarin. Dabigatran 150 mg increased gastrointestinal bleeds (p<0.001), and edoxaban 30 mg did not significantly reduce ischaemic strokes, compared to warfarin (p<0.001).

Conclusion: This systematic review found that DOACs are non-inferior to warfarin for stroke/systemic embolism prevention. Regardless of a drug’s characteristics on paper, the choice of anticoagulant should be individualised for each patient.

Disclosures: This review was completed by one investigator (undergraduate pharmacy student). The author has no conflicts of interest or sources of funding to disclose. This review was not registered.


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