Group Cognitive Behavioural Analysis System of Psychotherapy (CBASP) for persistently depressed outpatients: a retrospective chart review

Background Cognitive behavioural analysis system of psychotherapy (CBASP) is an effective individual treatment for persistent depressive disorder (PDD), but evidence on group treatment (Group‐CBASP) is limited. Our aim was to review the effect of Group‐CBASP on self‐report depression severity in outpatients with PDD, overall and by age of depression‐onset. Methods A retrospective chart review study (November 2011–March 2017) in 54 patients with PDD (29 late‐onset, 25 early‐onset). Patients were previously treated by pharmacotherapy (92.6%), psychotherapy (98.1%) and/or electroconvulsive therapy (11.1%). Group‐CBASP involved 24 weekly sessions during 6 months, followed by individual appointments over 6 months. The Inventory of Depressive Symptoms ‐self rating(IDS‐SR) was used at baseline and after 3, 6, 9 and 12 months, computing mean differences and response rates. Results The mean IDS‐SR score decreased significantly from 39.83 at baseline to 33.78 at 6 months: a decrease from severe to moderate depression after 24 weeks of Group‐CBASP, with a medium effect size (Cohen’s d = .49). At 12 months, the mean IDS‐SR score was 32.81, indicating moderate symptom levels remained. At 6 and 12 months, mean IDS‐SR scores were similar among late‐ versus early‐onset patients, but at 12 months response rates were higher among late‐onset patients. Limitations Although results of our study provide valuable input for future prospective studies, limitations were the use of a retrospective design and the small group size. Conclusion Group‐CBASP offered to an outpatient population with PDD was associated with clinically relevant decrease in self‐reported symptom severity, and with sustained response particularly in patients with late onset of depression. Practitioner points Group‐CBASP seems to be a good alternative for CBASP in individual setting. Patients with late age of depression‐onset seem to benefit more from Group‐CBASP. This study shows that clinical relevant effects of Group‐CBASP, followed by individual contacts, remain at least for 6 months. Research on personalizing treatment strategies is needed to improve patient assignment for Group‐CBASP.