OBJECTIVE:Depression is associated with increased risk for obesity and worse weight loss treatment outcomes. The purpose of the present study was to test the hypothesis that delivering evidence-based behavior therapy for depression before a lifestyle weight loss intervention improves both weight loss and depression.

DESIGN:In a randomized controlled trial, obese women with major depressive disorder (N=161, mean age=45.9 (s.d.: 10.8) years) were randomized to brief behavior therapy for depression treatment followed by a lifestyle intervention (BA) or a lifestyle intervention only (LI). Follow-up occurred at 6 and 12 months. Main outcome measures included weight loss and depression symptoms.

RESULTS:Intention-to-treat analyses revealed both conditions lost significant weight, but no differences between conditions in weight change at 6 months (BA=-3.0%, s.e.=-0.65%; LI=-3.7%, s.e.=0.63%; P=0.48) or 12 months (BA=-2.6%, s.e.=0.77%; LI=-3.1%, s.e.=0.74%; P=0.72). However, the BA condition evidenced significantly greater improvement in Beck Depression Inventory-II scores relative to the LI condition at both 6 months (BA mean change=-12.5, s.d.=0.85; LI mean change=-9.2, s.d.=0.80, P=0.005) and 12 months (BA mean change=-12.6, s.d.=0.97; LI mean change=-9.9, s.d.=0.93; P=0.045). Participants who experienced depression remission by 6 months (61.2%) lost greater weight (mean=-4.31%; s.e.=0.052) than those who did not (39.7%; mean=-2.47%, s.e.=0.53; P=.001).

CONCLUSION:Adding behavior therapy to a lifestyle intervention results in greater depression remission but does not improve weight loss within 1 year. Improvement in depression is associated with greater weight loss.