Specialized post-inpatient psychotherapy for sustained recovery in anorexia nervosa via videoconference – study protocol of the randomized controlled SUSTAIN trial

BACKGROUND: A major barrier to long-term recovery from anorexia nervosa (AN) are early and frequent relapses after inpatient treatment. There is an urgent need for enhanced continuity of specialized care involving effective aftercare interventions and relapse prevention strategies in order to improve the long-term outcome for patients with AN. METHODS: SUSTAIN is a multi-center, prospective, randomized-controlled trial investigating the efficacy of a novel post-inpatient aftercare intervention for patients with AN as compared to optimized treatment-as-usual (TAU-O). The SUSTAIN aftercare intervention is based on the cognitive-interpersonal maintenance model of AN and specifically tailored to achieve sustained recovery in AN following inpatient treatment. The SUSTAIN aftercare intervention comprises 20 treatment sessions over eight months and will be predominantly delivered via videoconference to overcome discontinuity of care. TAU-O refers to routine outpatient psychotherapy as generally offered in the German health care system. A total number of 190 patients receiving inpatient or day-hospital treatment for AN will be randomized and assessed over a 14-month period following randomization including a 6 months follow-up. Minimum Body Mass Index (BMI) is 15 kg/m(2) at trial inclusion. The primary efficacy endpoint is the change in BMI between baseline (T0) and end of treatment (T2) adjusted for baseline BMI. Key secondary outcomes comprise eating disorder and general psychopathology, quality of life, proportion of relapse and of weight restoration, and cost-effectiveness. DISCUSSION: The results of the present trial will provide evidence if the novel aftercare intervention fosters sustained recovery in patients affected by severe courses of AN. TRIAL REGISTRATION: The SUSTAIN trial was prospectively registered on November 18, 2020, under the registration number DRKS00023372 at the German Clinical Trials Register (https://www.drks.de/drks_web/) which is an acknowledged primary register of the World Health Organization (http://apps.who.int/trialsearch/). Protocol version: 1.2.