Epileptic seizures after stroke: Risk factors and long term follow up

Purpose: Stroke is the most common cause of new onset seizures in adults and elderly people. The purpose of this study is to determine the factors affecting the incidence of early and late onset seizures after stroke, seizure frequency of patients in the long-term follow-up, factors determining single and recurrent seizures, treatment response, the effect of early, or late seizures on stroke prognosis. Material and method: Between January 1999 and December 2015, patients from the Neurology Department of the Medical Faculty of Karadeniz Technical University were retrospectively collected and 218 patients with epileptic seizures after stroke were included in the study. Stroke types were classified as ischemic, hemorrhagic and ischemic secondary hemorrhage. Patients who had seizures after stroke were divided into two groups as early and late seizure groups. Patients who had a seizure on the first 7 days after stroke were classified as early seizure and those who had seizure on the 7th day and later were classified as late seizure. Single and recurrent seizure subgroups were formed in early and late seizure groups. Seizures occurred within 24 hours were considered as single epileptic seizures and two or more seizures that were separated from the first one by more than 24-hour were classified as recurrent seizures. Both groups and subgroups were compared in terms of demographic characteristics (age, sex), stroke type and etiology, stroke history, neuroradiological findings, EEG findings, seizure type and frequency, treatment and prognosis after treatment. Results: Frequency of seizures after stroke was found %9,3. The frequency of early-onset seizures after stroke was % 3,2, late-onset seizure frequency was %6,1. It was found that severity of MRS in hospital discharge and lesion in cortico-subcortical localization increased probability of late seizure (p<0,05). The rate of single seizure was 73,7% and the rate of recurrent seizure was 26,3% in the early seizure group. Severity of MRS in hospital admission was found to be a risk factor for recurrence in early seizure group (p=0,025). The rate of single seizure was 41,5% and the rate of recurrent seizure was 58,5% in the late seizure group. In the late seizure group, it was found that an inverse association between the presence of large artery atherosclerosis and recurrent seizures (p=0,024). Conclusion: Post-stroke seizures are more commonly seen as late seizures than early seizures. Early seizures appear more often as a single seizure while late seizures have a higher recurrence rate. It was found that severity of stroke and large stroke lesion increasing the risk of late seizure. In addition to this, seizure recurrence in the late seizure group was found to be higher. Keywords: post stroke seizures, early seizure, late seizure, single seizure, recurrent seizure