Comparison of different direct oral anticoagulant regimens in atrial fibrillation patients with high bleeding risk

BACKGROUND The optimal dose of direct oral anticoagulants (DOACs) to prevent ischemic stroke (IS) and systemic thromboembolism (STE) in atrial fi brillation (AF) patients with a predisposing bleeding risk remains unclear. OBJECTIVE The purpose of this study was to compare the effectiveness and safety of different DOAC dosage regimens in AF patients with high bleeding risk but low thrombosis risk. METHODS This retrospective observational study was conducted with the National Health Insurance claims database in Taiwan to include AF patients aged 20 up to 75 years, under DOAC therapy, with CHA(2)DS(2) -VASc score of 1 for males and 2 for females and HAS-BLED score > 3. Standard -dose regimen was de fi ned as dabigatran 300 mg, rivaroxaban 20 mg, apixaban 10 mg, or edoxaban 60 mg per day. Any other lower-dose regimen were de fi ned as the low-dose regimen. The primary outcomes were IS and major bleeding (MB). The secondary outcomes were STE, gastrointestinal bleeding, intracranial hemorrhage, and cardiovascular death. RESULTS A total of 964 patients were included (52.1% standard -dose regimen). Median HAS-BLED score was 3 [interquartile range 3 -3]. Compared with standard -dose group, patients in the low-dose group had a signi fi cantly increased risk of IS (adjusted hazard ratio [aHR] 5.13; 95% con fi dence interval 1.37 -19.22) and STE (aHR 3.14 [1.05 -9.37]) but similar risk of MB (aHR 0.45 [0.12 -1.67]). The risks of other hemorrhage and cardiovascular death were similar between the 2 dose groups. CONCLUSION Among patients with a predominant bleeding risk but relatively low thrombosis risk, the low-dose DOAC regimen is not a more appropriate selection than standard -dose regimen.