Impact of Collateral Circulation on Poststroke Epilepsy After Mechanical Thrombectomy for Large Vessel Occlusive Stroke: A Multicenter Cohort Study

Background Acute ischemic stroke (AIS) represents a significant etiology of acquired epilepsy in adults. However, there remains a paucity of evidence concerning predictive factors for poststroke epilepsy (PSE) among patients undergoing mechanical thrombectomy (MT). We aimed to evaluate the association between poor collateral circulation and the risk of PSE. Methods This multicenter cohort study included AIS patients who underwent MT (2017–2022) at three tertiary centers. Adjusted Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for PSE risk. Subgroup analyses, sensitivity analyses, and competing risk analyses were also performed. Results We included 1167 patients (mean age: 62 years; 46.5% female). PSE frequency was higher in the poor collateral circulation group compared to the control group (13.0% vs. 4.2%, p < 0.001). Patients with inadequate collateral circulation ( ASITN / SIR < 2) showed significantly increased risks of both 12‐month PSE and 60‐month PSE development ( HR > 1, p < 0.05) compared to those with adequate collateral status ( ASITN / SIR ≥ 2) following MT for AIS . Conclusions Poor collateral circulation is associated with PSE and may help identify individuals at high risk for PSE.