Preadmission oral anticoagulant therapy and clinical outcome in patients hospitalised with acute stroke and atrial fibrillation

INTRODUCTION: Information about the effect of preadmission oral anticoagulant therapy (OAT) on stroke outcome in patients with atrial fibrillation (AF) is scarce. A systematic review was done of the existing data on the association between preadmission OAT and stroke outcome in patients with AF.METHOD: We performed a systematic search in the PubMed Database, the Embase Database and the Cochrane Database of Systematic Reviews identifying 13 studies that met the inclusion criteria.RESULTS: The studies included a total of 18,523 patients with AF and admission with stroke. Of these, 1,169 had a haemorrhagic stroke. The proportion of patients in preadmission OAT varied from 5 to 37%, and the proportion who did not receive any antithrombotic therapy (AT) varied from 22 to 75%. The risk of having a severe stroke for patients with an international normalised ratio (INR) < 2 ranged from 26 to 43% compared with a 15-36% range for patients with an INR ≥ 2. The risk of death or disability among patients not receiving any AT ranged from 22 to 56% compared with 15-59% for those on platelet inhibitors, 16-48% for those on OAT with an INR < 2 and 6-37% among patients with an INR ≥ 2. These patterns were confirmed after adjustment for confounding factors.CONCLUSION: Only a minority of AF patients with stroke received OAT at the time of hospitalisation. Overall, preadmission OAT was associated with less severe strokes and a lower risk of death or disability. Further efforts seem warranted to ensure OAT for all eligible AF patients.