Non-vitamin K antagonist oral anticoagulants versus warfarin in AF patients ≥ 85 years

Abstract

Background: Atrial fibrillation (AF) prevalence and its risk of stroke rise with ageing. We aimed to investigate the outcomes of NOAC and warfarin in AF patients aged ≥ 85 years.

Methods: This is a retrospective study using Taiwan National Health Insurance Research Database. A total of 15,361 patients aged ≥ 85 years with AF on oral anticoagulants were identified. The end points included ischaemic stroke, intracranial haemorrhage (ICH), major bleeding, all-cause mortality and composite adverse events (ICH or major bleeding or all-cause mortality). Clinical outcomes were compared between each NOAC and warfarin after propensity matching.

Results: Before propensity matching, patients taking warfarin were older, more female with more comorbidities than NOACs users. After propensity matching, baseline characteristics did not differ significantly between matched subjects receiving warfarin and each NOAC. Compared to warfarin, dabigatran was associated with a lower risk of ICH (hazard ratio [HR] 0.496), mortality (HR 0.558) and adverse events (HR 0.628), while rivaroxaban was associated with a lower risk of ischaemic stroke (HR 0.781), ICH (HR 0.453), mortality (HR 0.558) and adverse events (HR 0.636). Apixaban was associated with a lower risk of mortality (HR 0.488) and adverse events (HR 0.557) compared to warfarin. (all P < .05).

Conclusion: For the efficacy, NOACs were associated with a comparable or lower risk of ischaemic stroke compared to warfarin. For adverse events, NOACs were associated with a lower risk of all-cause mortality and composite adverse events. In the elderly AF population, NOACs could be a more favourable choice for stroke prevention.

Keywords: NOACs; atrial fibrillation; elderly; warfarin.