Abstracts

Rationale: Traumatic Brain Injury (TBI) is a well-known risk factor for post-traumatic epilepsy (PTE), especially among survivors of penetrating head injuries such as gun shot wounds (GSW), assaults, and blast injuries. We sought to enroll new civilian TBI patients into a prospective study designed to predict the onset of PTE through computerized analysis of electroenchalography (EEG) and microRNA biomarkers with a target enrollment of 90 patients. One critical component of a prospective study such as this is a reasonable expectation of enrollment and an understanding as to why a majority of TBI patients are poor study subjects. Methods: This is an ongoing study. We screened all new TBI patients upon admission as a Level 1 trauma to St. Joseph's Hospital and Medical Center (SJHMC) beginning October 16, 2011. Criteria for enrollment included moderate to severe penetrating or closed head injuries (initial Glasgow Coma Score (GCS) <13), with no previous diagnosis of epilepsy, and not participating in another clinical trial. If the patient was unable to sign for him or herself, families were approached with information about the study and the legally authorized representative was asked to sign for consent. Results: To date (6/15/12) 111 patients who came through SJHMC as a Level 1 trauma patient who had sustained moderate to severe TBI (mean age: 38, GCS at admission: 7.1, mean lowest GCS: 5.7) have been screened for enrollment. Of these, 85 patients were ineligible for study for a variety of reasons; 33 died from their injuries (mean time from injury to death = 6.4 days), 13 lived far from the Phoenix Metropolis and would be unable to return, 10 were not interested, 8 were chronic alcoholics, 7 had a history of seizure disorders, 4 were polysubstance abuse users with suicidal ideologies, and 12 were rejected for other reasons. Of the 26 enrolled, 3 died from their injuries, 5 suffered acute traumatic seizures (but have not yet developed PTE) and 5 were withdrawn. This means only 12.6% of all moderate to severe Level 1 TBI patients are active study participants. Mechanisms of injury were as follow: motor vehicle collision (30), auto vs. pedestrian (20), GSW (14), motorcycle crash (14), assault (11), fall (10), ATV accident (8), and other (4). Alcohol was a factor in 60% of all injuries; 36% of patients were positive for other substances including but not limited to cocaine, marijuana, and opiates, and amphetamines. Conclusions: Prospective clinical studies of PTE after TBI which require long-term follow-up are difficult. Our experience has been that only 1 of 8 such patients (12.6%) could be enrolled and continuously followed over six or more months. This experience should be considered when planning a long term follow-up study of moderate to severe TBI patients with either penetrating or closed head injuries.