Functional outcomes of patients with ischaemic stroke with known atrial fibrillation not on therapeutic anticoagulation

BACKGROUND: Anticoagulation significantly reduces the risk of ischaemic stroke in patients with atrial fibrillation (AF). There are a proportion of patients with known AF who remain off anticoagulation. Aims This study aims to retrospectively compare the baseline characteristics, treatments and functional outcomes between patients with ischaemic stroke and known AF based on their anticoagulation status. METHODS: A single-centre, retrospective review of consecutive patients with an ischaemic stroke and a known history of AF was conducted. RESULTS: Two hundred four patients with an ischaemic stroke had documented AF prior to the index admission, of which 126 were anticoagulated. Median admission National Institutes of Health Stroke Scale score was lower for anticoagulated patients, though not statistically significant (5.1 vs 7.0, P = 0.09). Median baseline modified Rankin score (mRS) did not significantly differ. Nonanticoagulated patients were more likely to have large vessel occlusions (37.2% vs 23.8%, P = 0.04) and more likely to receive intravenous thrombolysis (15.4% vs 1.6%, P < 0.01). There was no difference in rates of endovascular clot retrieval between groups (P > 0.05). Unfavourable functional outcome at 90 days (mRS ≥ 3) did not significantly differ between groups (P = 0.51). A total of 38.5% of nonanticoagulated patients had no documented reason for this. Of the patients who survived the index admission, 81.5% of patients who were not anticoagulated on admission received anticoagulation. CONCLUSIONS: Baseline anticoagulation was associated with milder stroke severity in ischaemic stroke patients with known AF. There was no significant difference in functional outcomes at 90 days between groups. Larger observational studies are required to further assess this cohort.