Cognitive behavioral analysis system of psychotherapy versus interpersonal psychotherapy for early-onset chronic depression: a randomized pilot study

Abstract

Background: The only psychotherapy specifically designed and evaluated for the treatment of chronic depression, the Cognitive Behavioral Analysis System of Psychotherapy (CBASP), has never been directly compared to another depression-specific psychological method.

Methods: Thirty patients with early-onset chronic depression were randomized to 22 sessions of CBASP or Interpersonal Psychotherapy (IPT) provided in 16 weeks. Primary outcome was the score on the 24-item Hamilton Rating Scale for Depression (HRSD) assessed posttreatment by an independent blinded evaluator. Secondary endpoints were, among others, remission (HRSD≤8) rates and the Beck Depression Inventory (BDI). The study included a prospective naturalistic 12-month follow-up.

Results: Intent-to-treat analyses of covariance (ANCOVA) revealed that there was no significant difference in posttreatment HRSD scores between the CBASP and the IPT condition, but in self-rated BDI scores. We found significantly higher remission rates in the CBASP (57%) as compared to the IPT (20%) group. One year posttreatment, no significant differences were found in the self-reported symptom level (BDI) using ANCOVA.

Limitations: The study used only a small sample size and no placebo control. The generalizability of the results may be limited to patients with a preference for psychological treatment.

Conclusions: While the primary outcome was not significant, secondary measures showed relevant benefits of CBASP over IPT. We found preliminary evidence that in early-onset chronic depression, an approach specifically designed for this patient population was superior to a method originally developed for the treatment of acute depressive episodes. Long-term results suggest that chronically depressed patients may need extended treatment courses.