Early Computed Tomography Frontal Abnormalities Predict Long-Term Neurobehavioral Problems But Not Affective Problems after Moderate to Severe Traumatic Brain Injury

Behavioral problems are serious consequences of moderate to severe traumatic brain injury (TBI) and have a negative impact on outcome. There may be two types: neurobehavioral problems, manifesting as inadequate social behavior resulting from prefrontal system damage, and affective behavioral problems, resulting from emotional distress as a reaction to the brain injury. In the present study we investigated whether these two types of behavioral problems, as indicated by proxies, could be distinguished in a group of chronic TBI patients and whether early indicators of prefrontal damage on imaging could predict long-term neurobehavioral problems. Computed tomography (CT) imaging data on admission were used to identify frontal lesions. Three hundred twenty-three moderate to severe TBI survivors received 2 to 16 years post-trauma an aftercare survey with seven questions asking for changes in behavior and affect, presented both to patients and their proxies. One hundred eighty-six patients (59%) answered the behavioral questions; 42% had frontal lesions on CT. Ordinal common factor analysis on proxy scores yielded two factors, with behavior and affective items clearly separated and the anger item mediocre related to both factors. Three scales were created: Behavior, Affective and Anger. Frontal patients scored significantly higher on the Behavior and Anger scales. Logistic regression analysis showed a fourfold increase of long-term neurobehavioral problems in patients with frontal lesions. Long-term neurobehavioral problems were significantly correlated to one-year outcome and return to work in the long term. We conclude that in patients with moderate to severe TBI neurobehavioral and affective problems can be distinguished. Early CT frontal abnormalities predict long-term neurobehavioral problems, but not affective problems.