Day-patient treatment after short inpatient care versus continued inpatient treatment in adolescents with anorexia nervosa (ANDI): a multicentre, randomised, open-label, non-inferiority trial

Background In-patient treatment (IP) is the treatment setting of choice for moderately-to-severely ill adolescents with anorexia nervosa, but it is costly, and the risks of relapse and readmissions are high. Day patient treatment (DP) is less expensive and might avoid problems of relapse and readmission by easing the transition from hospital to home. We investigated the safety and efficacy of DP after short inpatient care compared with continued IP. Methods For this multicentre, randomised, open-label, non-inferiority trial, we enrolled female patients (aged 11-18 years) with anorexia nervosa from six centres in Germany. Patients were eligible if they had a body-mass index (BMI) below the tenth percentile and it was their first admission to hospital for anorexia nervosa. We used a computer-generated randomisation sequence to randomly assign patients to continued IP or DP after 3 weeks of inpatient care (1:1; stratified for age and BMI at admission). The treatment programme and treatment intensity in both study groups were identical. The primary outcome was the increase in BMI between the time of admission and a 12-month follow-up adjusted for age and duration of illness (non-inferiority margin of 0.75 kg/m(2)). Analysis was done by modified intention to treat. This trial is registered with the International Standard Randomised Controlled Trial Number Register, number ISRCTN67783402, and the Deutsches Register Klinischer Studien, number DRKS00000101. Findings Between Feb 2, 2007, to April 27, 2010, we screened 660 patients for eligibility, 172 of whom we randomly allocated to treatment:85 to IP and 87 to DP. DP was non-inferior to IP with respect to the primary outcome, BMI at the 12-month follow-up (mean difference 0.46 kg/m(2) in favour of DP (95% CI, -0.11 to 1.02; p(non-inferiority) < 0.0001). The number of treatment-related serious adverse events was similar in both study groups (eight in the IP group, seven in the DP group). Three serious adverse events in the IP group and two in the DP group were related to suicidal ideation; one patient in the DP attempted suicide 3 months after she was discharged. Interpretation DP after short inpatient care in adolescent patients with non-chronic anorexia nervosa seems no less effective than IP for weight restoration and maintenance during the first year after admission. Thus, DP might be a safe and less costly alternative to IP. Our results justify the broad implementation of this approach.