Warfarin superior to aspirin for stroke prevention in AF: BAFTA

Among patients over age 75 years with atrial fibrillation, anticoagulation with warfarin was superior to aspirin for primary stroke prevention, results of the Birmingham Atrial Fibrillation Treatment of the Aged (BAFTA) trial show. “In summary, these data lend support to the use of anticoagulation for all people aged over 75 years who have atrial fibrillation, unless there are contraindications or the patient decides that the size of the benefit is not worth the inconvenience of the treatment,” Dr Jonathan Mant (University of Birmingham, UK), and colleagues conclude in their report published in the Lancet. The researchers enrolled 973 patients aged 75 years or over with atrial fibrillation from primary care and randomly assigned them to warfarin (target international normalised ratio 2—3) or aspirin (75 mg per day). Follow-up was for a mean of 2·7 years. The primary endpoint was fatal or disabling stroke (ischaemic or haemorrhagic), intracranial haemorrhage, or clinically significant arterial embolism. There were 24 primary events (21 strokes, two other intracranial haemorrhages, and one systemic embolus) in people assigned to warfarin and 48 primary events (44 strokes, one other intracranial haemorrhage, and three systemic emboli) in people assigned to aspirin (yearly risk 1·8% vs 3·8%, relative risk 0·48, 95% CI 0·28—0·80, p=0·003; absolute yearly risk reduction 2%, 95% CI 0·7—3·2). Yearly risk of extracranial haemorrhage was 1·4% (warfarin) versus 1·6% (aspirin) (relative risk 0·87, 0·43—1·73; absolute risk reduction 0·2%, -0·7 to 1·2). “These data support the use of anticoagulation therapy for people aged over 75 who have atrial fibrillation, unless there are contraindications or the patient decides that the benefits are not worth the inconvenience,” the researchers conclude. “The target INR should be 2—3—a range in which there is clear evidence of benefit and no evidence from this study of harm compared with aspirin. Age itself should not be regarded as a contraindication to anticoagulation therapy,” they add. Reference Mant, J. Hobbs, R. et al. 2007, ‘Warfarin versus aspirin for stroke prevention in an elderly community population with atrial fibrillation (the Birmingham Atrial Fibrillation Treatment of the Aged Study, BAFTA): a randomised controlled trial’ Lancet, vol. 370, pp. 370:493-503....