The Incidence of Early Seizures in Non-Severe Traumatic Brain Injury Patients and the Efficacy of Prophylactic Antiepileptic Drugs

The incidence of early seizures (ES) in traumatic brain injury (TBI) ranges between 1 and 7%. However, the incidence of ES after a non-severe TBI (NSTBI) with traumatic hemorrhage (TH) is unknown. Moreover, the data about seizure prophylaxis (SP) in this population remains inconclusive. We aim to determine the incidence of ES in NSTBI and the efficacy of SP. We retrospectively reviewed all adult patients with NSTBI with evidence of a TH on presentation from 2015 to 2018 at Methodist University Hospital in Memphis TN. Patients with history of epilepsy or receiving antiseizure medications (ASM) were excluded. We collected demographic data, the type, severity, and mechanism of injury; the need for neurosurgical intervention (NSI); ES; and SP use. A total of 633 patients met our inclusion criteria; 94.4% had mild TBI; mean age was 70.5 years (SD 16.9); 55.0% were males; and 49.1% had subdural hematoma (SDH). Same level fall was the most common mechanism of injury in 79%. Forty patients (6.3%) had ES. After excluding seizures on presentation, 22 of 310 (7.1%) patients had an ES in the SP group (16 clinical) vs 5 of 310 (1.6%) in the non-prophylaxis group (all clinical) (P = 0.001). Levetiracetam as SP was used in 83.5%. Patients with combined SDH and traumatic subarachnoid hemorrhage or with multicompartment hemorrhage were more likely to have ES than SDH alone (p = 0.02 and 0.001, respectively). NSI was not a predictor for ES in our cohort. The incidence of ES (clinical and electrographic) in NSTBI with TH patients in our cohort is higher than previously reported in those with non-severe TBI. ES were reported more in the SP group, which might indicate a clinical selection bias giving more moderate TBI and multicompartmental hemorrhage patients receiving ASM for SP. However, prospective studies are required to further determine the predictors of ES in non-severe TBI and the effect of ASM for SP on outcomes and reducing ES in NSTBI patients.