Effectiveness of enhanced cognitive behavior therapy for eating disorders: A randomized controlled trial

OBJECTIVE

Enhanced cognitive behavior therapy (CBT-E) is a transdiagnostic treatment suitable for the full range of eating disorders (EDs). Although the effectiveness of CBT(-E) is clear, it is not being used as widely in clinical practice as guidelines recommend. The aim of the present study was to compare the effectiveness of CBT-E with treatment as usual (TAU), which was largely based on CBT principles.

METHOD

We conducted a randomized controlled trial on a total of 143 adult patients with an ED who received either CBT-E or TAU. The primary outcome was recovery from the ED. Secondary outcome measures were levels of ED psychopathology, anxiety, and depressive symptoms. Self-esteem, perfectionism, and interpersonal problems were repeatedly measured to examine possible moderating effects. We explored differences in duration and intensity between conditions.

RESULTS

After 80 weeks, there were no differences between conditions in decrease in ED psychopathology, or symptoms of anxiety and depression. However, in the first six weeks of treatment there was a larger decrease in ED psychopathology in the CBT-E condition. Moreover, when the internationally most widely used definition of recovery was applied, the recovery rate at 20 weeks of CBT-E was significantly higher (57.7%) than of TAU (36.0%). At 80 weeks, this difference was no longer significant (CBT-E 60.9%; TAU 43.6%). Furthermore, CBT-E was more effective in improving self-esteem and was also the less intensive and shorter treatment.

DISCUSSION

With broader use of CBT-E, the efficiency, accessibility and effectivity (on self-esteem) of treatment for EDs could be improved.

Effectiveness of enhanced cognitive behavioral therapy (CBT-E) for eating disorders: study protocol for a randomized controlled trial

BACKGROUND

While eating disorder not otherwise specified (EDNOS) is the most common eating disorder (ED) diagnosis in routine clinical practice, no specific treatment methods for this diagnosis have yet been developed and studied. Enhanced cognitive behavioral therapy (CBT-E) has been described and put to the test as a transdiagnostic treatment protocol for all EDs, including EDNOS. Initial research in the UK suggests that CBT-E is more effective for EDs, especially bulimia nervosa (BN) and EDNOS, than the earlier version of CBT. These positive results of CBT-E have to be replicated in more detail, preferably by independent researchers in different countries. Being the first Dutch study into CBT-E, the results from this national multicenter study - on three sites specialized in EDs - will deliver important information about the effectiveness of CBT-E in several domains of ED pathology, while providing input for the upcoming update of the Dutch Multidisciplinary Guideline for the Treatment of Eating Disorders.

METHODS/DESIGN

A multicenter randomized controlled trial will be conducted. One hundred and thirty-two adult outpatients (aged 18 years and older) with an ED diagnosis and a Body Mass index (BMI) of between 17.5 and 40 will be randomly allocated to the control or the intervention group. Subjects in the control group will receive Treatment as Usual (standard outpatient treatment provided at the participating sites). Subjects in the intervention group will receive 20 sessions of CBT-E in 20 weeks. The design is a 2 (group) × 5 (time) repeated measures factorial design in which neither therapists nor patients will be blinded for treatment allocation. The primary outcome measure is recovery from the ED. Secondary outcome measures include ED psychopathology, common mental disorders, anxiety and depressive symptoms, health-related quality of life, health care use and productivity loss. Self-esteem, perfectionism and interpersonal problems will be examined as putative predictors and mediators of the effect of treatment. Also, an economic evaluation from a societal perspective will be undertaken. All relevant effects, direct and indirect costs will be included. Utility scores will measure the effects. Measurements will take place at pretreatment, 6 weeks, 20 weeks, 40 weeks and 80 weeks.

DISCUSSION

This effectiveness study into CBT-E has the aim of broadening the scope and generalizability of former studies. If CBT-E appears to be at least as effective as traditional diagnosis-specific treatments for a broad range of ED patients, training in one protocol would be sufficient for clinicians to treat patients with different kinds of EDs. It gives the opportunity to offer treatment for a severe mental disorder with fewer resources, thereby increasing the accessibility of specialized care for patients with an ED.

TRIAL REGISTRATION

Netherlands Trial Register, NTR4485 . Registered on 2 April 2014.