Reduced-dose DOACs tied to lower stroke incidence vs warfarin

Patients with atrial fibrillation receiving a reduced dose of direct acting oral anticoagulants (DOAC), particularly rivaroxaban and dabigatran, show a similar incidence of ischaemic stroke and systemic embolism to those receiving warfarin, a study has shown.

However, the incidence is lower among those who received apixaban. Additionally, DOAC-treated patients have a similar or lower rate of intracranial haemorrhage than those treated with warfarin.

In this observational study, researchers used nationwide administrative databases from Denmark, Sweden, Norway, and Finland, covering 1 January 2011 to 31 December 2018 (2017 for Sweden). A total of 26,883 patients who initiated reduced-dose DOACs and 108,014 warfarin-treated patients were included in the analysis.

Researchers measured effectiveness through the composite endpoint of ischaemic stroke and systemic embolism and assessed safety through intracranial haemorrhage rates.

Based on the meta-analysis, the incidences of ischaemic stroke and systemic embolism were similar or lower in patients on reduced-dosed DOACs relative to those on standard warfarin (rivaroxaban: hazard ratio [HR], 0.93; dabigatran: HR, 0.88; apixaban: HR, 0.79). Compared to DOAC recipients, warfarin-treated patients had incidences of 2.16 to 3.71 per 100 person-years.

In terms of safety, the rates of intracranial haemorrhage were low across all patient groups, with a range of 0.16 to 1.85 per 100 person-years. The HRs for rivaroxaban, dabigatran, and apixaban were 1.41, 0.35, and 0.72, respectively, when compared with warfarin.