Prospective evaluation of a post-stroke epilepsy risk scale

Background and Purpose: Ischemic and hemorrhagic strokes are established etiological factors for recurrent seizures. Still only few prospective data is available to predict post-stroke epilepsy and to choose the best time-point and anticonvulsive agent for treatment.

Methods: In a prospective study we evaluated 264 consecutive stroke patients and assessed their post-stroke epilepsy risk within a follow-up of 1 year. Data on ten risk items concerning the stroke localisation, persisting neurological deficit, stroke subtype, established diagnosis of vascular encephalopathy, early and late seizures was collected using a self-designed “post-stroke epilepsy risk scale“. All patients underwent brain imaging with CT, MRI or both and 148 patients underwent electroencephalography.

Results: The overall frequency of early seizures within 14 days was 4.5%, of at least one late seizure 6.4% and of epilepsy 3.8%. Chi-Square tests showed significantly higher relative frequencies of seven of the ten clinical characteristics in post-stroke epilepsy patients. The total scale showed moderate sensitivity (70%) and positive predictive value (87.5%) while specifity (99.6%) and negative predictive value (98.8%) were relatively high. The EEG showed little value in predicting post-stroke epilepsy.

Conclusions: The post-stroke epilepsy risk scale appears to be a valueable tool to predict the risk for post-stroke epilepsy within the first few days after a stroke.