Abstract W MP66: Rates of Ischemic Stroke after Intracranial Hemorrhage in a Population-Based Sample of Patients with Atrial Fibrillation
Introduction: Patients with atrial fibrillation (AF) who experience intracranial hemorrhage (ICH) often cannot tolerate anticoagulant therapy and presumably face a higher risk of thromboembolism. However, there are little population-based data on long-term rates of stroke after ICH in patients with AF.
Methods: Using validated diagnosis codes and administrative claims data from all nonfederal acute care hospitals and emergency departments in California, Florida, and New York from 2005 to 2012, we identified patients at their first encounter with a recorded diagnosis of AF. We excluded patients with diagnoses of stroke or ICH prior to their index visit or a diagnosis of stroke at the index visit. A time-varying covariate was used to account for ICH (intracerebral or subarachnoid hemorrhage) at the index visit or during follow-up. Kaplan-Meier survival statistics were used to calculate cumulative rates of stroke, and Cox proportional hazard analysis was used to evaluate the relationship between incident ICH and stroke while adjusting for the CHA2DS2VASc score.
Results: During a mean 3.2 years of follow-up among 2,376,207 patients with AF, 25,243 (1.06%) developed ICH and 93,183 (3.92%) developed stroke. The cumulative 1-year rate of stroke was 6.50% (95% CI, 6.06-6.96%) after ICH versus 2.22% (95% CI, 2.20-2.24) in those without ICH. ICH remained associated with higher stroke risk after adjusting for the CHA2DS2VASc score (HR, 2.29; 95% CI, 2.18-2.40). Among patients with ICH, stroke risk rose in step with the CHA2DS2VASc score.
Conclusions: In a large population-based cohort, patients with AF faced a substantially higher risk of stroke after ICH. This risk rose proportionally with increasing CHA2DS2VASc score. These findings point to patients with AF and ICH as a vulnerable population who may especially benefit from therapeutic alternatives to anticoagulant therapy for preventing thromboembolism in AF.
Author Disclosures: M.P. Lerario: None. G. Gialdini: None. D. Lapidus: None. M. Shaw: None. B. Navi: Research Grant; Significant; Florence Gould Endowment for Discovery in Stroke. H. Kamel: Research Grant; Significant; Grant K23NS082367 from NIH/NINDS.
- © 2015 by American Heart Association, Inc.