Prevalence and Risk Factors for Early Seizure in Patients with Traumatic Brain Injury: Analysis from National Trauma Data Bank

Background: Traumatic brain injury (TBI) is a well-known risk factor for seizures. We aimed to identify the frequency and risk factors for seizure occurrence during hospitalization for TBI. Methods: We used ICD-9-CM codes to identify patients 18 years of age or older from the National Trauma Data Bank who were admitted with TBI. We also used ICD-9-CM codes to identify the subset who had seizures during hospitalization. Patient demographics, comorbidities, Glasgow Coma Scale (GCS) score, Injury Severity Score Abbreviated Injury Scale (ISSAIS), in-hospital complications, and discharge disposition were compared in the seizure group (SG) and no-seizure group (NSG). Results: A total of 1559 patients had in-hospital seizures, comprising 0.4% of all patients admitted with TBI. The mean age of SG was 3 years older than NSG [51 vs. 48; p < 0.0001]. African-American ethnicity (20 vs. 12%, p < 0.0001) and moderate TBI (8 vs. 4%, p < 0.0001) were more common in SG. History of alcohol dependence was more common in the SG (25 vs. 11%, p < 0.0001). Fall was the most common mechanism of injury in SG (56 vs. 36% in NSG; p < 0.0001). Subdural hematoma was more common in SG (31 vs. 21%, p < 0.0001). SG had higher rates of pneumonia, ARDS, acute kidney injury, and increased ICP. The average length of hospital stay was significantly higher in SG (10 vs. 6 days, p < 0.0001), and these patients had higher rate of discharge to nursing facility (32 vs. 25%, p < 0.0001). Conclusion: In-hospital seizures occur in 0.4% of all TBI patients. Although infrequent, seizure occurrence is associated with higher rates of hospital complications such as pneumonia and ARDS and is an independent predictor of longer hospital stay and worse hospital outcome.