The Relations of Cognitive, Behavioral, and Physical Activity Variables to Depression Severity in Traumatic Brain Injury: Reanalysis of Data From a Randomized Controlled Trial.

OBJECTIVE: To explore the relations of cognitive, behavioral, and physical activity variables to depression severity among people with traumatic brain injury (TBI) undergoing a depression treatment trial. SETTING: Community. PARTICIPANTS: Adults (N = 88) who sustained complicated mild to severe TBI within the past 10 years, met criteria for major depressive disorder, and completed study measures. DESIGN: Randomized controlled trial. METHODS: Participants were randomized to cognitive-behavioral therapy (n = 58) or usual care (n = 42). Outcomes were measured at baseline and 16 weeks. We combined the groups and used regressions to explore the relations among theoretical variables and depression outcomes. MAIN MEASURES: Depression severity was measured with the Hamilton Depression Rating Scale and Symptom Checklist-20. Theory-based measures were the Dysfunctional Attitudes Scale (DAS), Automatic Thoughts Questionnaire (ATQ), Environmental Rewards Observation Scale (EROS), and the International Physical Activity Questionnaire (IPAQ). RESULTS: Compared with non-TBI norms, baseline DAS and ATQ scores were high and EROS and IPAQ scores were low. All outcomes improved from baseline to 16 weeks except the DAS. The ATQ was an independent predictor of baseline depression. An increase in EROS scores was correlated with decreased depression. CONCLUSIONS: Increasing participation in meaningful roles and pleasant activities may be a promising approach to treating depression after TBI.