Anticoagulants for preventing stroke in patients with nonrheumatic atrial fibrillation and a history of stroke or transient ischaemic attack

BACKGROUND: People with nonrheumatic atrial fibrillation (NRAF) who have had a transient ischaemic attack (TIA) or a minor ischaemic stroke are at high risk of recurrent stroke. OBJECTIVES: The objective of this review was to assess the effect of anticoagulants for secondary prevention, after a stroke or TIA, in patients with NRAF. SEARCH STRATEGY: We searched the Cochrane Stroke Group trials register (9 June 2003) and contacted trialists. SELECTION CRITERIA: Randomised trials comparing oral anticoagulants with control (no therapy) or placebo in people with NRAF and a previous TIA or minor ischaemic stroke. Control groups on aspirin did not meet the selection criteria. DATA COLLECTION AND ANALYSIS: Both reviewers assessed trial quality and extracted data. MAIN RESULTS: Two trials involving 485 people were included. Follow-up time was 1.7 years in one trial and 2.3 years in the other. Anticoagulants reduced the odds of recurrent stroke by two-thirds (odds ratio (OR) 0.36, 95% confidence interval (CI) 0.22 to 0.58). The odds of all vascular events was shown to be almost halved by treatment (OR 0.55, 95% CI 0.37 to 0.82). The odds of major extracranial haemorrhage was increased (OR 4.32, 95% CI 1.55 to 12.10). No intracranial bleeds were reported among people given anticoagulants. REVIEWERS' CONCLUSIONS: The evidence suggests that anticoagulants are beneficial, without serious adverse effects, for people with NRAF and recent cerebral ischaemia.