Seizure frequency in patients with isolated subdural hematoma and preserved consciousness

Background: Seizures are a complication of subdural hematoma (SDH), and there is substantial variability in the use of seizure prophylaxis for patients with SDH. However, the incidence of seizures in patients with SDH without severe neurotrauma is not clear. The objective of this study was to assess the frequency of and factors associated with seizures in patients with isolated SDH (iSDH) without severe neurotrauma. Methods: In this retrospective, observational study, we identified adults with Glasgow Coma Score (GCS) ≥13 and computed tomography (CT)-documented iSDH. The primary outcome was clinical seizure frequency. Seizure medication use was also assessed. Fisher's exact test and logistic regression were used to assess association. Results: Of 643 patients with iSDH, 14 (2.2%) had seizures during hospitalization. Of 630 patients (98%) not receiving seizure medication prior to SDH, 522 (82.9%) received levetiracetam. Of the patients who received a seizure medication, 12 (2.3%) had a seizure, while of the 121 patients who did not receive seizure medications, 2 (1.9%) had a seizure (p = .49). In multivariable regression, the only variable significantly associated with seizure was thickness of subdural hematoma (OR 1.16, p = .005). Conclusion: In patients with iSDH and preserved consciousness, in-hospital seizures were rare regardless of seizure medications use.