Natural history of depression in traumatic brain injury.

OBJECTIVE: To examine prospectively the rates, risk factors, and phenomenology of depression over 3 to 5 years after traumatic brain injury (TBI).

DESIGN: Inception cohort longitudinal study.

SETTING: Level I trauma center.

PARTICIPANTS: Consecutive admissions of 283 adults with moderate to severe TBI.

INTERVENTIONS: Not applicable.

MAIN OUTCOME MEASURE: Center for Epidemiologic Studies Depression (CES-D) Scale.

RESULTS: The rates of moderate to severe depression ranged from 31% at 1 month to 17% at 3 to 5 years. With 1 exception, the relation between brain injury severity and depression was negligible. Less than high school education, preinjury unstable work history, and alcohol abuse predicted depression after injury. Examination of CES-D factors indicate that, in addition to somatic symptoms, both depressed affect and lack of positive affect contribute to elevated CES-D scores.

CONCLUSIONS: High rates of depressive symptoms cannot be dismissed on grounds that somatic symptoms related to brain injury are mistaken for depression. Depressed affect and lack of positive affect are also elevated in persons with TBI. Preinjury psychosocial factors are predictive of depression and knowing them should facilitate efforts to detect, prevent, and treat depression after TBI.