Depression following traumatic brain injury: Impact on post-hospital residential rehabilitation outcomes.

Background: A need exists to better understand the impact of depression on functional outcomes following TBI.
Objectives: To evaluate the prevalence and severity of depression among a large group of chronic TBI adults; to determine the impact of depression on outcomes of post-hospital residential rehabilitation programs; and to assess effectiveness of post-hospital residential rehabilitation programs in treating depression.
Methods: 820 adults with moderate to severe traumatic brain injury (TBI) were assigned to one of four groups based on MPAI- 4 depression ratings: (1) Not Depressed, (2) Mildly Depressed, (3) Moderately Depressed, and (4) Severely Depressed. Functional status was assessed at admission and discharge with the MPAI-4 Participation Index. Differences among groups were evaluated using conventional parametric tests. Rasch analysis established reliability and validity of MPAI-4 data.
Results: Rasch analysis demonstrated satisfactory construct validity and internal consistency (Person reliability = 0.89-0.92, Item reliability = 0.99). Of the 820 subjects, 39% presented with moderate to severe depressive symptoms at admission, These subjects demonstrated significantly higher MPAI-4 Participation scores than the mild and not depressed groups. Depressed groups realized significant improvement in symptoms, but, those remaining depressed at discharge had significantly greater disability than those who improved.
Conclusions: Depressive symptoms had a deleterious impact on outcome. Remediation of symptoms during rehabilitation significantly improved outcomes.