Seizures after stroke : a prospective clinical study

Stroke is one of the most common causes of epilepsy in elderly. However, there have been very few prospective studies to define the incidence, pattern and outcome of seizures in stroke. Most studies are based on retrospective analysis of hospital records. Hence, we planned this prospective study to see the clinical, radiological and electroencephalographic characteristics of seizures in stroke and their outcome, from a north Indian tertiary care centre. Over a span of approximately 6 years, 269 consecutive patients with stroke were studied and followed up. Thirty-five (13%) of these developed seizures, primarily related to stroke, during mean follow up period of 15.9 months. Twenty of these had infarctions while 15 had haemorrhages. Involvement of the cortical region was seen in most of the patients with seizures. In these patients, 86% of the lesions involved cortical areas exclusively or in addition to subcortical areas on CT scan of the brain. Twenty-seven (77%) developed early seizures, two third of them had immediate post-stroke seizures. None of the patients with early onset seizures developed recurrent seizures or epilepsy, while 50% of late onset seizures developed epilepsy. No specific EEG pattern was found in those who later developed epilepsy. In the present study, early onset seizures after stroke were rather common and did not affect outcome and did not recur even when not treated with anti-epileptics. Late onset seizures were less common but were associated with recurrent seizures.