Surgery for epilepsy secondary to vascular insults: A systematic review and meta-analysis of individual patient data

While epilepsy secondary to vascular insults represents a well-documented cause of drug-resistant epilepsy that requires surgical intervention for optimal management, the prognostic factors for postoperative seizure-freedom among this patient population have not been well-established. This individual-patient data (IPD) meta-analysis aimed to 1) determine prognostic factors associated with seizure-freedom postoperatively and 2) factors associated with postoperative complications.

This study was a PRISMA-compliant systematic review and IPD meta-analysis involving studies relating to the surgical treatment of post-stroke epilepsy. An IPD meta-analysis was conducted using mixed-effects, multivariable logistic regression models to identify predictors of seizure freedom (Engels class I or International League Against Epilepsy [ILAE] class 1 or 2) and postoperative complications.

A total of 11 studies provided patient-level data for our IPD meta-analysis. Our results demonstrated that etiology of cerebrovascular insult, specifically ischemic or hemorrhagic stroke when compared to ulegyria, was significantly and independently associated with higher odds of postoperative seizure-freedom (OR=10.21, p = 0.031). Further, patients with a greater number of years between epilepsy onset and surgical treatment were significantly less likely to experience seizure-freedom postoperatively (OR=0.93, p = 0.023). Patients with ischemic or hemorrhagic strokes were significantly less likely to experience a postoperative complication relative to patients with ulegyria in univariate analysis (OR=0.053, p = 0.015), and this association remained significant in multivariable analysis (OR=0.16, p = 0.035).

Our findings synthesize the existing literature on the surgical treatment of stroke-related epilepsy and establish important prognostic factors for seizure-freedom in this patient population. We hope our results are useful in guiding future research efforts and further optimizing postoperative outcomes.