Apolipoprotein E4 as a Predictor of Outcomes in Pediatric Mild Traumatic Brain Injury

The epsilon 4 allele of the apolipoprotein E (APOE) gene has been linked to negative outcomes among adults with traumatic brain injury (TBI) across the spectrum of severity, with preliminary evidence suggesting a similar pattern among children. This study investigated the relationship of the APOE epsilon 4 allele to outcomes in children with mild TBI. Participants in this prospective, longitudinal study included 99 children with mild TBI between the ages of 8 and 15 recruited from consecutive admissions to Emergency Departments at two large children's hospitals. Outcomes were assessed acutely in the Emergency Department and at follow-ups at 2 weeks, 3 months, and 12 months post-injury. Among the 99 participants, 28 had at least one epsilon 4 allele. Children with and without an epsilon 4 allele did not differ demographically. Children with an epsilon 4 allele were significantly more likely than those without an epsilon 4 allele to have a Glasgow Coma Scale score of less than 15, but the groups did not differ on any other measures of injury severity. Those with an epsilon 4 allele exhibited better performance than children without an epsilon 4 allele on a test of constructional skill, but the groups did not differ on any other neuropsychological tests. Children with and without an epsilon 4 allele also did not differ on measures of post-concussive symptoms. Overall, the findings suggest that the APOE epsilon 4 allele is not consistently related to the outcomes of mild TBI in children.