Effect of disorder-specific vs nonspecific psychotherapy for chronic depression: A randomized clinical trial

Importance: Chronic depression is a highly prevalent and disabling disorder. There is a recognized need to assess the value of long-term disorder-specific psychotherapy. Objective: To evaluate the efficacy of the Cognitive Behavioral Analysis System of Psychotherapy (CBASP) compared with that of nonspecific supportive psychotherapy (SP). Design, setting, and participants: A prospective, multicenter, evaluator-blinded, randomized clinical trial was conducted among adult outpatients with early-onset chronic depression who were not taking antidepressant medication. Patients were recruited between March 5, 2010, and October 16, 2012; the last patient finished treatment on October 14, 2013. Data analysis was conducted from March 5, 2014, to October 27, 2016. Interventions: The treatment included 24 sessions of CBASP or SP for 20 weeks in the acute phase, followed by 8 continuation sessions during the next 28 weeks. Main outcomes and measures: The primary outcomewas symptom severity after 20 weeks (blinded observer ratings) as assessed by the 24-item Hamilton Rating Scale for Depression (HRSD-24). Secondary outcomes were rates of response (reduction in HRSD-24 score of ≥50% from baseline) and remission (HRSD-24 score ≤8), as well as self-assessed ratings of depression, global functioning, and quality of life. Results: Among 622 patients assessed for eligibility, 268 were randomized: 137 to CBASP (96 women [70.1%] and 41 men [29.9%]; mean [SD] age, 44.7 [12.1] years) and 131 to SP (81 women [61.8%] and 50 men [38.2%]; mean [SD] age, 45.2 [11.6] years). The mean (SD) baseline HRSD-24 scores of 27.15 (5.49) in the CBASP group and 27.05 (5.74) in the SP group improved to 17.19 (10.01) and 20.39 (9.65), respectively, after 20 weeks, with a significant adjusted mean difference of -2.51 (95%CI, -4.16 to -0.86; P = .003) and a Cohen d of 0.31 in favor of CBASP. After 48 weeks, the HRSD-24 mean (SD) scores were 14.00 (9.72) for CBASP and 16.49 (9.96) for SP, with an adjusted difference of -3.13 (95%CI, -5.01 to -1.25; P = .001) and a Cohen d of 0.39. Patients undergoing CBASP were more likely to reach response (48 of 124 [38.7%] vs 27 of 111 [24.3%]; adjusted odds ratio, 2.02; 95%CI, 1.09 to 3.73; P = .03)or remission (27 of 124 [21.8%] vs 14 of 111 [12.6%]; adjusted odds ratio, 3.55; 95%CI, 1.61 to 7.85; P = .002) after 20 weeks. Patients undergoing CBASP showed significant advantages in most other secondary outcomes. Conclusions and relevance: Highly structured specific psychotherapywas moderately more effective than nonspecific therapy in outpatients with early-onset chronic depression who were not taking antidepressant medication. Adding an extended phase to acute psychotherapy seems promising in this population.