Combined Cognitive-Behavioral Therapy and Placebo Treatment for Patients with Depression: A Follow-Up Assessment

Introduction: A previous study revealed that patients with depression who received a combination of cognitive-behavioral therapy (CBT) and placebo treatment (CBT+placebo) showed greater symptom reduction than a CBT group without a placebo. Moreover, the CBT +placebo group practiced relaxation training more frequently. We conducted a 3-month follow-up assessment to investigate the temporal stability of the placebo effects. Methods: Eighty-two outpatients with a diagnosis of major depressive disorder who had participated in a 4-week CBT course (CBT: n = 40; CBT with daily placebo treatment: n = 42) returned to a 3-month follow-up assessment. The participants of the CBT+placebo group had been debriefed directly after the course. Results: Compared to the CBT group, the CBT+placebo group had lower scores on the Beck Depression Inventory-II (BDI-II) at follow-up and more participants were below the clinical cut-off score of the BDI-II. Additionally, the CBT+placebo group continued to practice relaxation more frequently. Discussion: This study demonstrates that placebo effects are not short-lived and continue to be present after the debriefing.