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.