Greater Body Dissatisfaction at Admission Is Associated With Lower BMI at Discharge in Anorexia Nervosa: Predictive Validity of the Eating Pathology Symptoms Inventory

Abstract

People with anorexia nervosa (AN) engage in dietary restriction and other weight loss behaviors that result in dangerously low body weight, leading to an increased risk for mortality and medical complications. Weight gain is one of the most important indicators of treatment progress and recovery for AN. There are limited predictors of weight gain for patients with AN, making it difficult for clinicians to anticipate which patients are likely to respond favorably to treatment. Thus, there is a need to identify additional, potentially modifiable predictors of weight gain within a higher level of care for AN. This study tested the predictive validity of the Eating Pathology Symptoms Inventory (EPSI) in adults receiving a higher level of care for AN (N = 340). We hypothesized that EPSI scores at treatment admission would predict body mass index (BMI) at discharge. Linear regression was used to identify predictors of discharge BMI. EPSI Body Dissatisfaction at admission (β = -0.043, p = 0.005) predicted BMI at discharge (controlling for admission BMI, length of stay, and level of care), such that individuals with greater body dissatisfaction at admission had lower BMIs at treatment discharge. Other EPSI scales did not predict BMI. Results supported the predictive validity of EPSI Body Dissatisfaction for discharge weight in adults receiving a higher level of care for AN. Patients who are more dissatisfied with their bodies, despite having a dangerously low BMI at admission, may be at risk for poorer treatment outcomes.

Keywords: anorexia nervosa; bmi; eating disorders; eating pathology symptoms inventory; predictive validity; psychometrics; treatment outcomes.