Clinical features of late-onset poststroke seizures

Compared to the patients with early-onset seizures (ES), those with late-onset seizures (LS) have a high risk of epilepsy that is a feared complication after stroke. However, few studies have described detailed clinical features of LS in Japanese patients.

To elucidate the clinical features of LS, a series of 448 stroke patients (cerebral infarction n = 286; cerebral hemorrhage n = 162) in our hospital were retrospectively examined in this study. Stroke location was determined by computed tomographic and/or magnetic resonance imaging scans. Lesion size was evaluated using the Alberta Stroke Program Early Computed Tomographic Score. We examined occurrence rate, onset time, and recurrence rate of LS. In addition, clinical features of the infarction of LS and non-LS group were compared on age, gender, laterality, location, and extent, respectively.

LS occurred in 18 patients (4.0%). Of these, 17 experienced LS within 1.5 years after stroke. While epilepsy developed in none of the patients with ES, it developed in 33% of those with LS. Patients with cortical and a larger infarction involving the middle cerebral artery had at significantly greater risk of LS (P < .05).

Patients with cortical and a larger infarction involving the middle cerebral artery should be carefully observed because of a high risk of LS.