Metacognitive Interpersonal Therapy-Eating Disorders (MIT-ED) Versus CBT-E for Adults: A Proof-of-Concept Randomized Controlled Trial.

Objective: There is an urgent need for psychological therapies in Eating Disorders (ED) that target both eating disorder symptoms and broader aspects of psychological functioning, such as personality disorder (PD) features. We integrated Metacognitive Interpersonal Therapy, developed for treating PDs, with existing CBT techniques for eating disorders (MIT-ED). This psychotherapy targets aspects of ED that are not included in the transdiagnostic CBT-E model, specifically poor metacognition and interpersonal schemas.

Method: A proof-of-concept randomized clinical trial (RCT) recruited 21 individuals with non-underweight ED (Bulimia Nervosa, Binge Eating Disorder and ED Not Otherwise Specified) to 20 individual psychotherapy sessions of MIT-ED or CBT-E. Outcomes addressed ED-related characteristics and PD diagnosis. Measures were taken at baseline, 10 sessions, 20 sessions, and 3 months after treatment completion.

Results: MIT-ED had excellent retention to treatment with 1 drop-out compared to 6 for CBT-E. Descriptive analyses using completer analyses (n = 14) indicated that both MIT-ED and CBT-E resulted in reduced ED symptoms, impairment, and binge eating, and improved ED-related attitudes, although there was no difference between treatment arms. MIT-ED achieved more remissions from PD diagnosis.

Discussion: MIT-ED appeared to be a promising effective treatment for non-underweight ED. If replicated in larger samples, it would offer an alternative approach to enhancing recovery in ED.