Duration of PSSE Associated With Development of Post-Stroke Epilepsy

There is a higher likelihood of the development of post-stroke epilepsy (PSE) in patients who had longer duration of early-onset post-stroke status epilepticus (PSSE), according to a study published in Seizure.

Patients with early-onset acute PSSE who were admitted to Vall d’Hebron University Hospital in Barcelona, Spain, between February 2011 and April 2017 were included in the study (N=117). Exclusions included previous history of epilepsy, arteriovenous malformation, subarachnoid hemorrhage, and subdural hematoma. Patients underwent neuroimaging of the brain with CT or MRI scans and were clinically monitored during the acute/subacute phase of the stroke.

Recorded stroke-related variables included the affected artery territory, type and severity of stroke according to the National Institutes of Health Stroke Scale (NIHSS) score, and lesion size and etiology. Other variables included were demographic characteristics, smoking and alcohol use, psychiatric history, cognitive impairment, and functional disability at discharge after stroke. After 2015, the PSSE features recorded were timing from stroke at PSSE onset, NIHSS score at time of status epilepticus, and status epilepticus type, duration, and treatment.

Median NIHSS score at stroke onset was 11 (interquartile range [IQR], 4-16); 32 patients experienced an ischemic stroke (64%). In 26 patients, the middle cerebral artery territory was affected (52%). The median duration of PSSE was 12 hours (IQR, 4.69-57), and the episode resolved within 24 hours in 24 patients (48%). The risk of having seizures at long-term was slightly higher in patients who previously had a lengthier PSSE episode. Patients with PSSE >16 hours in length with the greatest risk of developing epilepsy long-term had estimated relapse rates within the first year of follow-up (79.5%; 95% CI, 41.5%-99.1% vs 21.8%; 95% CI, 7.4%-54.8%). There were no other clinical, stroke-related, or status epilepticus-related factors associated with a higher risk of seizure reoccurrence.

The observational nature of this study is its main limitation, along with the high mortality rate of the patients.

The investigators concluded that patients who have NIHSS >4 and status epilepticus duration >16 hours had a risk for recurrence within the first year greater than 60%, and thus may qualify for antiepileptic treatment at long-term. They caution further study is needed as these results may be secondary to the effect occurring in small remaining groups.

Reference

Abraira L, Toledo M, Guzmán L, et al. Long-term epilepsy after early post-stroke status epilepticus. Seizure. 2019;69:193-197.