Predicting long-term outcome following traumatic brain injury (TBI)

Objective: Traumatic brain injury (TBI) is the most common cause of brain damage, resulting in long-term disability. The ever increasing life expectancies among TBI patients necessitate a critical examination of the factors that influence long-term outcome. Our objective was to evaluate the contribution of premorbid factors (which were identified in our previous work) and acute injury indices to long-term functioning following TBI. Method: Eighty-nine participants with moderate-to-severe TBI were evaluated at an average of 14.2 years postinjury (range: 1-53 years) with neuropsychological battery, medical examination, clinical interviews, and questionnaires. Results: TBI severity predicted cognitive, social, and daily functioning outcomes. After controlling for injury severity, preinjury intellectual functioning predicted cognitive status, as well as occupational, social, emotional, and daily functioning. Preinjury leisure activity also predicted cognitive, emotional, and daily functioning, whereas socioeconomic status failed to predict any of these variables. Conclusion: Findings offer further support for the cognitive reserve construct in explaining significant variance in TBI outcome, over and above the variance explained by injury severity.