The Association Between Atrial Fibrillation and Poststroke Seizures is Influenced by Ethnicity and Environmental Factors

Goal: Epilepsy is a major complication of stroke. There have been suggestions that patients with cardioembolic stroke are at a greater risk of developing seizures than other stroke subtypes. However, the incidence of atrial fibrillation (AF) and cardioembolic stroke varies considerably across countries, generally higher in Western populations than in Asian populations. This study assessed whether ethnicity affects the association between AF and poststroke seizure (PSS) development. We hypothesized that Royal Melbourne Hospital ([RMH] Melbourne) patients will have significantly higher incidence of AF-related PSS than in the Jinling Hospital (Nanjing) population. Materials and Methods: This was a retrospective, multicenter cohort study including patients with anterior circulation ischemic stroke admitted between 2008 and 2015. Occurrences of PSS were ascertained by reviewing medical records or telephone follow-up. To test the hypothesis of an interaction between ethnicity and AF for PSS occurrence, a logistic regression model with AF and ethnicity together with an ethnicity-by-AF interaction term was used. Findings: Of 782 patients followed-up for seizure development at RMH, 247 (31.6%) patients had AF, of whom 10 (4%) developed PSS. Of 1185 patients followed-up and included at JH, 54 (4.8%) patients with AF, of whom 4 (7.4%) developed PSS. At RMH, no significant association was found between AF and PSS; odds ratio.75, 95% confidence interval.4-1.6, (P =.4). At JH, there was a significant association between AF and increased PSS: OR 4.0, 95% CI 1.3-12.1, (P =.01), P for interaction =.03. Conclusion: Further understanding of genetic risks and environmental differences across ethnic populations and the role in PSS is required.