Why are we waiting? The relationship between low admission weights and end of treatment weight outcomes

Inpatient eating disorder units are increasingly being asked to admit patients at lower BMI's, often delaying hospital treatment until medically unavoidable. This paper aims to explore the impact of this trend on treatment outcome. Eighty-two adults with anorexia nervosa admitted to a national inpatient eating disorder ward were assessed for BMI at admission, length of hospitalisation, discharge BMI and re-admission within 1-year post-treatment. In the current study, admission BMI was unrelated to amount of weight gain during treatment or to length of hospital stay. As such patients admitted at lower BMI's had significantly lower BMI's on discharge from treatment. Low admission BMI's were related to significantly higher likelihoods of re-admission within 1 year. This study provides strong evidence for the benefit of early treatment episodes and with more successful treatment outcomes being related to higher weights at start of treatment