Predictors of post-discharge seizures in aneurysmal subarachnoid hemorrhage using EEG data

The predictors of post-discharge seizures using electroencephalogram (EEG) features in patients with aneurysmal subarachnoid hemorrhage (aSAH) remain understudied. We sought to identify predictors of seizures in aSAH survivors after hospital discharge.

We conducted a retrospective study of a consecutive cohort of aSAH patients admitted to an academic center from 2016 to 2024. Univariable and multivariable analysis was performed to evaluate the association between clinical, radiographic and EEG variables and post-discharge seizure occurrence.

We reviewed 626 SAH cases with suspected aneurysmal etiology and included 352 aSAH survivors (mean age 57 years [SD 13.6], 61 % female, 71 % white). Post-discharge seizures were more common in patients who had seizure on presentation or during hospitalization (33 % vs 11 %; p = 0.009), had intra-parenchymal hemorrhage (IPH) on admission (61 % vs 18 %; p < 0.001), longer hospital length of stay (p = 0.032), higher scores on modified Rankin Scale at discharge (p = 0.048), and higher need for prescription of anti-seizure medications at discharge (p < 0.001). EEG data revealed highly epileptic features and diffuse slowing were more common in patients who had seizures after hospital discharge (p < 0.001) compared to those who did not. However, in a multivariable analysis only IPH (OR 3.75, 95 % CI 1.3-10.9; p = 0.014) and diffuse slowing on EEG (OR 3.67, 95 % CI 1.18-11.4; p = 0.022) remained independent predictors of post-discharge seizure.

IPH and diffuse slowing on EEG may predict post-discharge seizure in survivors of aSAH. Larger prospective studies are needed to better risk stratify and justify the prescription of anti-seizure medications in a subset of aSAH survivors.