Blood thinners sharply cut stroke-related events in intermediate-risk AF
In the randomized SINGLE-AF trial, direct oral anticoagulants reduced serious clinical events by 69% among atrial fibrillation patients judged to have an intermediate stroke risk. The improvement came mostly from fewer ischemic strokes, and major bleeding did not rise. The results were presented at ESC Congress 2026 and published in the New England Journal of Medicine.
SINGLE-AF randomized 1,803 South Korean patients with atrial fibrillation and intermediate stroke risk—CHA2DS2-VASc 1 for men or 2 for women—at 18 centers. Participants received apixaban or rivaroxaban, or no anticoagulant, and were followed for two years.
The primary composite outcome included stroke, systemic embolism, major bleeding, and cardiovascular death. It occurred in 0.5% on DOACs versus 1.5% without. Ischemic stroke rates were 0.1% versus 1.1%; major bleeding was 0.3% versus 0.5%.
If confirmed, these findings may reassure clinicians and patients with intermediate-risk AF about starting DOACs, potentially preventing some strokes and reducing related disability or hospital care. Because major bleeding did not rise in this trial, some patients who currently forgo anticoagulation could reconsider treatment with their doctors. Guidelines panels may weigh this randomized evidence, though longer-term and broader-population effects remain uncertain.