The association between mild traumatic brain injury and psychiatric conditions.

The majority of patients with mild traumatic brain injury (TBI) recover fairly quickly and are usually restored to their previous level of functioning. However, a significant minority have prolonged, complicated, or incomplete recoveries and have outcomes disproportionately worse than would have been predicted by the objective facts of the injury. This failure to recover as expected was the focus of this study. The participants were 80 adults with actual or suspected mild TBI who were referred to an outpatient mild TBI clinic. Most were characterized by problematic recoveries. The results indicated that those individuals who only had brain injuries made good recoveries, but that those with psychiatric comorbidity did not (chi(2) = 19.65, p = 0.0002). Most of the new psychiatric conditions responsible for poor recovery consisted of depression, anxiety disorders or conversion disorder. Dissociative phenomena appeared common after mild TBI and scores on the Dissociative Experiences Scale predicted brain injury outcome with 77% accuracy.