A study recently published in the American Journal of Cardiology has explored the bleeding risk associated with oral anticoagulants (OACs) in patients with atrial fibrillation. Although direct oral anticoagulants (DOACs) have a favourable bleeding safety profile in comparison to warfarin, the bleeding safety profiles related to individual DOACs remain uncertain. Researchers identified 423,450 patients with atrial fibrillation from 2013-2015, of which 64% were treated with OACs (66% warfarin, 15% rivaroxaban, 12% dabigatran and 7% apixaban).
6.9% of patients experienced a major bleeding event. The incidence of intracranial haemorrhage was lower in patients using rivaroxaban (hazard ratio [HR] 0.73; 95% CI 0.64-0.84), dabigatran (HR 0.56; 95% CI 0.48-0.65), and apixaban (HR 0.70; 95% CI 0.55-0.90) in comparison to those who used warfarin. The risk of major gastrointestinal bleed was increased in patients using rivaroxaban (HR 1.20; 95% CI 1.12-1.27), but decreased in dabigatran (HR 0.88; 95% CI 0.82-0.95) and apixaban (HR 0.84; 95% CI 0.74-0.95) users. For any DOAC compared to warfarin, major bleeding events were more prevalent in patients aged ≥75 years than in patients aged <75 years. With the exception of rivaroxaban and gastrointestinal bleeding, it was concluded that the individual DOAC bleeding safety profiles were more favorable than warfarin in patients with atrial fibrillation. This relative safety benefit was reduced in DOAC users aged 75 years and over.
Contributed by Australian Medication Safety Services Associate – Isabella Singh