B-50
The Natural History of Neurocognitive Outcome from the Sub-Acute Recovery Phase to 1-Year Post-Injury in Military-Related Mild-Moderate Traumatic Brain Injury

Extract

Objective: The purpose of this study was to examine the natural history of neurocognitive functioning following mild-moderate traumatic brain injury (TBI) from the sub-acute recovery phase to 1-year post-injury. Method: Participants were n = 36 service members who sustained a mild-moderate TBI (91.7% male) and n = 10 who sustained orthopedic injuries without brain injury (i.e., Trauma Controls; 90.0% male). Participants were evaluated within 6-months post-injury (M = 3.7, SD = 2.0) and again at 1-year post-injury (M = 11.7, SD = 0.5). Participants completed a neuropsychological test battery that included 30 common neurocognitive measures. Participants were excluded for poor effort. Results: In the Sub-acute phase, compared to the TC group, lower scores (i.e., significant differences [p < .05] and/or meaningful effect sizes [d>.35]) were found in the TBI group on measures of verbal fluency, visual scanning, and executive functioning (d = .35-.93); with higher scores on measures of attention (d = .58). At 1-year post-injury, lower scores were found in the TBI group on measures of delayed memory, auditory memory, verbal fluency, executive functioning, and attention (d = .30-.46). In the TBI group, improvements over time were noted in the areas of auditory learning, verbal fluency, processing speed, immediate/delayed memory, and auditory/visual memory (d = .36-79). In the TC group, substantial improvements over time were noted in the vast majority of cognitive domains (d = .47-1.50). Conclusion: Compared to a TC group, worse neurocognitive outcome was found following mild-moderate TBI at both the sub-acute recovery phase and 1-year post-injury. However, the TBI group did experience improvement in many cognitive domains over time; but to a much lesser extent than the improvement experienced by those without TBI.