Impact of apolipoprotein gene on cognitive impairment and recovery after traumatic brain injury

The presence of the e4 allele may have a negative influence on response to injury and recovery in patients with traumatic brain injury (TBI).1,2 However, no study to date has included an uninjured control group to examine whether the influence of the e4 allele might be independent of TBI. In this study, we investigated whether presence of the e4 allele in patients with TBI results in greater impairments of memory, attention, executive function, and functional outcome 3, 6, and 12 months postinjury, and in slower recovery, than in patients without the e4 allele and uninjured controls. Following ethics approval and informed consent, 120 patients with moderate–severe TBI, aged 16 to 64 years, with no history of previous neurologic or psychiatric disorder were assessed 3, 6, and 12 months postinjury. They comprised 69.2% men, with mean Glasgow Coma Scale score (GCS) 8.24 (SD = 4.17, range = 3 to 15), mean post-traumatic amnesia (PTA) 26.14 days (SD = 28.64, range = <1 to 135), mean age 32.66 years (SD 13.38, range = 17 to 64), mean education 12.48 years (SD = 2.38, range = …