Abstracts

Rationale: Epilepsy is one of the major complications of stroke. We aimed to establish whether there is an association between intravenous thrombolysis, intra-arterial thrombolysis and post stroke seizure development. A better understanding of the relationship between acute stroke therapies and the development of seizures may lead to improved post stroke monitoring and follow-up. Methods: This was a retrospective, multicentre cohort study conducted at the Royal Melbourne Hospital and Nanjing General Hospital. We included patients with anterior circulation ischemic stroke admitted to the two hospitals between 2008 and 2015. Patients included were divided into 4 mutually exclusive groups based on the type of acute reperfusion treatment received: 1. IV-tPA only, 2. IAT and IV-tPA, 3. IAT only and 4. stroke unit care only (i.e. no IV-tPA or IAT). Patients with post stroke seizures were identified if they experienced seizures up to two years from stroke onset. Occurrence of post stroke seizures was ascertained by reviewing follow-up medical records, contacting the patients’ primary care physicians, or via a validated telephone questionnaire. To assess the association between the types of reperfusion treatment on seizure incidence we used multivariable logistic regression models where we adjusted for age, stroke severity, 3-month outcome and the identified prognostic factors within the treatment groups. Results: A total of 1943 patients with anterior circulation ischaemic stroke were included in the analysis (757 from Melbourne and 1186 from Nanjing). There were 1375 stroke unit care patients, 363 IV-tPA, 205 IAT and 93 IAT (without IV-tPA). The incidence of seizures across the groups was 2% after stroke unit care, 5.8% after IV-tPA, 8.3% after IAT and 12.9% in IAT (no IV-tPA). There was a significant association between patients treated with IV-tPA and seizure development in comparison to controls; OR: 2.5, p=0.009 95% CI (1.3-5.0). A significant association between patients treated with IAT and seizure development was found in comparison to controls; OR: 3.2, p=0.006, 95% CI (1.4-7.4). IAT (no IV-tPA) was significantly associated with seizure development in comparison to controls; OR: 3.8, p=0.005, 95% CI (1.5-9.6). Haemorrhagic transformation was a risk factor for seizure development in the IAT and IAT (no IV-tPA) groups (p=0.008 and p=0.011 respectively). Conclusions: Patients undergoing reperfusion therapies in acute stroke, such as IV-tPA and IAT were significantly more likely to develop seizures than patients without acute therapies. Patients undergoing IV-tPA and/or IAT for acute ischaemic stroke may benefit from longer stroke follow-up, particularly IAT treated patients who had haemorrhagic transformation. Funding: International Research and Research Training Fund (IRRTF)