Body weight perception in the treatment of anorexia nervosa Assessment of changes in biometric figure rating scales over the course of inpatient treatment

Background: Weight gain in the context of inpatient treatment for anorexia nervosa typically leads to an update of two core symptoms: fear of weight gain and high importance of a low body weight for self-esteem. Objective: To assess the use of a biometric figure rating scale for monitoring of the fear of gaining weight and the body image during inpatient treatment of anorexia nervosa, the dynamic developments in actually perceived and ideal body weight as indicators of fear of weight gain and body image were exploratively examined in a case series. Material and methods: A biometric figure rating scale optimized for underweight to normal weight is used. On this scale 13 inpatients diagnosed with typical anorexia nervosa marked the 2 bodies that most closely matched the patients' actual body and ideal body after the weekly weighing appointments. The data were compared with the weight gain trajectories. Results: A total of 128 weighing appointments were evaluated. Generally, answers were differentiated and varied over time in three typical patterns: (1) constant dissatisfaction with the body weight and accurate estimation with little weight change, (2) constant dissatisfaction with the body weight and accurate estimation with constant gain, (3) changing dissatisfaction with the body weight and accuracy, which jumped depending on the weight trajectory. Conclusion: The observations support the validity of figure rating scales for monitoring of cognition and affect with respect to one's own body weight in the inpatient treatment of anorexia nervosa. The interpretation of the scales should only be done in individual cases with the addition of further information.