a1 The University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA
a2 Truman State University, Kirksville, MO, USA
a3 University of Iowa, Iowa City, IA, USA
a4 University of Pennsylvania, Philadelphia, PA, USA
Background Major depressive disorder (MDD) is highly prevalent, is recurrent, and impairs people's work, relationships and leisure. Acute-phase treatments improve psychosocial impairment associated with MDD, but how these improvements occur is unclear. In this study, we tested the hypotheses that reductions in depressive symptoms exceed, precede and predict improvements in psychosocial functioning.
Method Patients with recurrent MDD (n=523; 68% women, 81% Caucasian, mean age 42 years) received acute-phase cognitive therapy (CT). We measured functioning and symptom severity with the Social Adjustment Scale – Self-Report (SAS-SR), Range of Impaired Functioning Tool (RIFT), Beck Depression Inventory (BDI), Hamilton Rating Scale for Depression (HAMD) and Inventory for Depressive Symptomatology – Self-Report (IDS-SR). We tested cross-lagged correlations between functioning and symptoms measured at baseline and the beginning, middle and end of acute-phase CT.
Results Pre- to post-treatment improvement in psychosocial functioning and depressive symptoms was large and intercorrelated. Depressive symptoms improved more and sooner than did psychosocial functioning. However, among four assessments across the course of treatment, improvements in functioning more strongly predicted later improvement in symptoms than vice versa.
Conclusions Improvements in psychosocial functioning and depressive symptoms correlate substantially during acute-phase CT, and improvements in functioning may play a role in subsequent symptom reduction during acute-phase CT.
(Received February 01 2011)
(Revised June 14 2011)
(Accepted June 18 2011)
(Online publication July 25 2011)