A novel 6-variable score incorporating clinical and neuroimaging features can predict post-stroke epilepsy (PSE), according to study findings published in Neurology.Stroke is one of the most common causes of adult-onset epilepsy, and PSE — defined as the occurrence or recurrence of unprovoked seizures more than 7 days after stroke — remains a clinically important complication following ischemic stroke.

Researchers developed a PSE prediction model (IsCHEMiA score) using a prospective stroke registry of patients consecutively admitted for acute ischemic stroke at Massachusetts General Hospital (MGH) between January 1, 2016, and December 31, 2018. The derivation cohort included 1436 patients, among whom the mean age was 67.4 years, and 54.7% were men.

 

In the evolving era of personalized medicine, the IsCHEMiA score may serve as the first step in identifying patients with acute ischemic stroke at a higher risk of PSE.

External validation was conducted in 3 independent international cohorts comprising 2534 patients from Queen Mary Hospital (QMH; n=1286), Ruttonjee Hospital (RH; n=272), and the National Cerebral and Cardiovascular Center (NCVC; n=976). Across cohorts, PSE occurred in 5.9% of patients at MGH, 5.1% at QMH, 5.1% at RH, and 5.5% at NCVC. Any post-stroke seizure occurred in 6.0%, 5.6%, 5.1%, and 8.3% of patients, respectively. Overall, PSE occurred in 5.5% of the total study population.

In the derivation cohort, PSE was associated with status epilepticus within 7 days of stroke (subdistribution hazard ratio [SHR], 13.1; 95% CI, 2.47-69.8; P =.0025), early symptomatic seizure within 7 days of stroke (SHR, 7.74; 95% CI, 3.22-18.6; P <.0001), acute symptomatic seizure within 7 days of stroke (SHR, 6.98; 95% CI, 2.75-17.7; P <.0001), and parenchymal hemorrhage-1 (SHR, 6.18; 95% CI, 3.14-12.2; P <.0001).

After backward stepwise elimination, significant predictors included infarct size 5 cm or larger (adjusted SHR [aSHR], 4.87; 95% CI, 2.75-8.65; P <.0001), early symptomatic seizures within 7 days of stroke (aSHR, 4.69; 95% CI, 1.84-11.9; P =.001), hemorrhagic transformation (aSHR, 4.34; 95% CI, 2.58-7.30; P <.0001), middle cerebral artery territory involvement (aSHR, 2.47; 95% CI, 1.18-5.17; P =.016), and age younger than 65 years (aSHR, 1.86; 95% CI, 1.20-2.89; P =.006).

The infarct size, cortical involvement, hemorrhagic transformation, early seizures, middle cerebral artery involvement, and age younger than 65 years variables were incorporated into the IsCHEMiA score, which assigns 2 points for infarct size 5 cm or larger, 1 point for cortical involvement, 2 points for hemorrhagic transformation, 2 points for early seizures, 1 point for middle cerebral artery territory involvement, and 1 point for age less than 65 years.n external validation, the IsCHEMiA score demonstrated good discrimination, with c-statistics of 0.870 in the United States cohort and consistent performance across validation cohorts. The score also outperformed the SeLECT score for predicting PSE in the overall study population (c-statistic, 0.848 vs 0.782; P < .0001).

Study limitations include differences in post-stroke care and follow-up across international cohorts.

The study authors concluded, “In the evolving era of personalized medicine, the IsCHEMiA score may serve as the first step in identifying patients with acute ischemic stroke at a higher risk of PSE.”