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.

Introduction

Up to one third of all mood disorders take a chronic (defined as 2 years or more) course (Klein and Santiago, 2003, Klein, 2008) which implies that 2.5–6% of the Western population suffer from chronic depression (Kessler et al., 1994, Kessler et al., 2005, Torpey and Klein, 2008). Compared to acute major depressive episodes chronic depression is associated with greater comorbidity, more significant impairments in functioning, more interpersonal deficits, increased health care utilization, more frequent suicide attempts and hospitalizations, more early adversity, and earlier onset (for review see Arnow and Constantino, 2003, Torpey and Klein, 2008, Angst et al., 2009). Not surprisingly, patients with chronic depression are also more difficult to treat with both pharmacological and psychological approaches (Kocsis, 2003, Markowitz, 1995). In more than 70% of all cases, chronic depression begins before the age of 21 years (Cassano et al., 1992, Keller et al., 2000), is usually associated with early trauma (Lizardi et al., 1995, Wiersma et al., 2009), and frequently persists for the entire lifespan. Early-onset chronic depression results in a more substantial human capital loss than late-onset (Berndt et al., 2000). In addition, the disorder has a more malignant course than late-onset depression (Klein et al., 1999) and shows a high rate of relapse after an initial response to medication treatment (Agosti, 1999).

Although psychotherapy is commonly applied to long-term depressed patients in clinical practice (Angst et al., 2009), there has been only limited research on the efficacy of psychological interventions for chronic forms of depression. In a recent meta-analysis, psychotherapy had a small but significant effect on chronic depression when compared to control groups (Cuijpers et al., 2010). The approach with the strongest empirical support is the Cognitive Behavioral Analysis System of Psychotherapy (McCullough, 2000), the only psychotherapeutic method specifically designed for this disorder. One large trial (n = 681; Keller et al., 2000) showed that for a subgroup of chronic depressives with an early childhood trauma (Nemeroff et al., 2003), CBASP was particularly effective with and without additional medication. In contrast, medication (nefazodone) alone had a weak effect in this subgroup of patients as only 33% reached remission (48% with CBASP). Similarly, imipramine but also more traditional psychotherapies (IPT, and Cognitive Behavioral Therapy/CBT) performed relatively poorly in the subgroup of early-onset chronic depression as shown by a reanalysis (Agosti and Ocepek-Welikson, 1997) of the data from the NIMH-Collaborative study. In another trial (Markowitz et al., 2005) with early-onset patients suffering from dysthymia IPT modified for dysthymic disorders was no more successful than the control condition (supportive psychotherapy). However, in our own study (Schramm et al., 2008) a more intensive course of IPT plus medication in hospitalized patients with severe chronic major depression was superior to a standard psychiatric treatment.

Nevertheless, as an augmentation strategy for non- or partial responders to a medication algorithm (Kocsis et al., 2009) 12 sessions of CBASP did not fare better than the control conditions (supportive therapy or a medication switch). The data suggest that chronic depression requires more frequent sessions (Thase et al., 1994) and a longer duration of treatment (Gelenberg et al., 2003) and therefore the results of the study by Kocsis et al. (2009) need to be interpreted with caution.

In summary, while the results of the outlined trials are mixed, CBASP performed best in the subgroup of patients it was originally developed for by McCullough (2000): chronically depressed patients with early trauma (most of whom can be assumed to have early onset). The CBASP approach aims specifically at overcoming interpersonal, cognitive–emotive and other maturational deficits which resulted from early maltreatment by focusing on the therapeutic relationship. The IPT model which was originally designed for acute depressive episodes assumes that, independent from the causes, depression always occurs in a context of acute interpersonal stress (vulnerability–stress-model). Resolving current problem areas associated with the depression is the focus of IPT. It is the first comparison of these two theoretically distinct, depression-specific interventions in chronic depression. Our primary hypothesis was that in patients with early-onset chronic depression CBASP which is specifically tailored to the needs and deficits of this patient group would be superior to IPT in terms of reduction of depressive symptoms when applied in an intense manner (22 sessions in 16 weeks). The secondary hypothesis was that CBASP would lead to higher remission rates than IPT.