Vulnerability to disability following traumatic brain injury (TBI)

Abstract

There are an estimated 2 million TBIs each year in the United States of America. Psychosocial and neurobehavioral disorders, versus physical impairments, are the most disabling consequences of brain injury. There is a great deal of individual diversity in outcome that is poorly understood. To this date, most studies of outcome following TBI have focused on the effect of post-injury variables. These studies have generally employed gross measures of physical and cognitive status versus quality of life and adaptation to disability. Many studies have excluded persons with psychiatric and substance abuse histories. There is increasing appreciation that pre-injury characteristics such as coping history may influence outcome and that each person likely has a given level of vulnerability to disability following TBI This vulnerability likely reflects a complex combination of both premorbid and post-injury variables. This formulation provided the framework for this study of the outcome of moderate and severe traumatic brain injury survivors. Forty-five adults at least two years post moderate or severe TBI were evaluated. Preinjury psychiatric history and pre-injury substance abuse history in addition to social support following TBI were measured for each subject This study hypothesized that persons with more severe premorbid psychiatric histories and substance abuse histories in addition to less social support following brain injury would demonstrate poorer adaptation. Subjects were rated on four outcome measures: employment status, independent living status, self-assessment of neurobehavioral functioning, and a significant other's assessment of their neurobehavioral functioning. Pre-injury psychiatric and substance abuse histories predicted employment status. Pre-injury substance abuse history predicted independent living status. Social support following TBI predicted significant other's assessment of subject's neurobehavioral status. None of the independent variables were found to predict self assessment of neurobehavioral functioning.