Treatment of binge eating disorder with dialectical behaviour therapy

Binge eating disorder (BED) is characterised by recurrent episodes of uncontrollable overeating without the use of regular, inappropriate compensatory behaviours that are typical for bulimia nervosa. Behavioral weight loss (BWL), interpersonal psychotherapy (IPT) and cognitive behavioural therapy (CBT) have shown to reduce binge eating with the latter currently being the treatment of choice for BED. CBT helps to reduce binge eating substantially and leads to abstinence from binge eating in a proportion of patients. Estimates about the exact proportion vary widely across studies (e.g. Dingemans, et al. 2002; Munsch et al., 2007; Wilfley et al., 2002). General consensus seems to be that a substantial number of patients do not reach abstinence from binge eating. For this latter patient group, other treatment models should be developed in order to increase abstinence rates. One such treatment model is Dialectical Behavior Therapy (DBT). DBT for BED is based on the assumption that binge eating is a behavioural attempt to influence, change or control painful emotional states. In DBT patients are taught healthier affect regulation skills. Preliminary studies investigating the adaptation of DBT to target disordered eating have been promising in comparison to a wait-list. Compared to an active comparison therapy (credible placebo), there were no significant differences between the groups at any time during the follow-up period. The DBT group however achieved abstinence and reductions in binge frequency more quickly (e.g., at post treatment) and showed significantly fewer dropouts, 4% vs. 33,3% (Safer et al, 2010). Dropout in CBT ranges from 12% to 34% (Flueckiger et al. 2011). To our knowledge, direct comparison of DBT and CBT has never been conducted yet.
The present study assesses the effectiveness of DBT compared to treatment as usual (CBT+, which consists of a day treatment program offering CBT and psychomotor therapy) at our eating disorder treatment centre in patients with binge eating disorder using a randomized controlled design. We will examine whether DBT leads to similar or even better results than CBT+ with respect to binge frequency, eating disorder psychopathology, levels of emotional eating, alexithymia and impulsivity, general psychopathology (more specifically reduction of levels of depression and anxiety), decrease in body weight and waist circumference and in improvement of coping skills.

We expect to find that overall, DBT will show larger treatment effects than CBT+ while being less time-consuming than CBT+. More patients will respond to DBT than to CBT because it is assumed that DBT will also help for those patients that do not respond to CBT. More specific, we expect to find better results in terms of binge frequency, and eating disorder psychopathology for DBT. Given the nature of the intervention we do expect to find differences on emotional eating, alexithymia and impulsivity, in favour of DBT. On our tertiary outcome measures we do not expect to find any differences with dropout rate being the exception in favour of DBT.

Baseline assessment T0: just before treatment
T1: right after treatment

Follow-up measurements: ½ year (T2), 1 year (T3), 2 years (T4) and 4 years after treatment (T5).

- Emotion regulation skills training based on the Stanford Dialectical Behaviour Therapy protocol for binge eating disorder (DBT), without a diet advice or stimulation of physical exercise. This is a systematic skills training, aimed at training in mindfulness, emotion regulation and tolerance of distress. The treatment consists of a 20 sessions 2 hour group therapy and is given by two trained psychologists/psychotherapists.

- Cognitive Behavioural Therapy + (CBT+), based on the cognitive model of eating disorders. The program focuses on normalizing eating behaviour (i.e. creating and maintaining a regular eating pattern, stop bingeing), raising body awareness and optimizing physical movement. Used techniques are psycho-education, self-monitoring, self-control, cognitive restructuring and psychomotor therapy. The treatment consists of 20 days of group therapy and is given by one trained cognitive-behavioural therapist, one trained sociotherapist and one trained psychomotor therapist.