Influence of Demographic, Clinical, and Neuroimaging Variables on Neuropsychological Recovery Trajectories After Moderate-to-Severe Traumatic Brain Injury

Traumatic brain injury (TBI) is prevalent in people of all ages and all walks of life. Cognitive deficits are common after TBI and the recovery patterns are known to be variable across individuals. The current study investigates diffuse axonal injury (DAI), cerebral blood flow (CBF), and focal lesions, in addition to post-traumatic amnesia (PTA), as possible predictors of cognitive trajectory in moderate-to-severe TBI patients. Cognitive trajectory was evaluated with a battery of neuropsychological tests that were combined into three domains: processing speed, verbal learning, and executive function. Patients (N=44) were tested three times at 3, 6, and 12 months post-injury. A linear mixed effects model was used for analyses to account for individual differences in longitudinal changes. Results displayed significant fixed effects of DAI, CBF, PTA, age, and education. However, age was the only moderator of neuropsychological recovery trajectory. Future studies would benefit from a larger sample size and including additional assessment time points including more acute phase and longer-term follow-up evaluations in later years post-injury