Changes in appetite-regulating hormones following food intake are associated with changes in reported appetite and a measure of hedonic eating in girls and young women with anorexia nervosa

Background: Females with anorexia nervosa (AN) have higher ghrelin and peptide YY (PYY) and lower brainderived neurotropic factor (BDNF) levels than controls, and differ in their perception of hunger cues. Studies have not examined appetite-regulating hormones in the context of homeostatic and hedonic appetite in AN. Objective: To examine whether alterations in appetite-regulating hormones following a standardized meal are associated with homeostatic and hedonic appetite in young females with AN vs. controls. Methods: 68 females (36 AN, 32 controls) 10-22 years old were enrolled. Ghrelin, PYY and BDNF levels were assessed before, and 30, 60 and 120 min following a 400-kilocalorie standardized breakfast. Visual Analog Scales (VAS) assessing prospective food consumption, hunger, satiety, and hedonic appetite were administered before and 20 min after breakfast. A Cookie Taste Test (CTT) was conducted after a snack as a measure of hedonic eating behavior similar to 3 h after breakfast. Results: AN had higher fasting ghrelin and PYY, and lower fasting BDNF (p = 0.001, 0.002 and 0.044 respectively) than controls. Following breakfast (over 120 min), ghrelin and PYY area under the curve (AUC) were higher, while BDNF AUC was lower in AN vs. controls (p = 0.007, 0.017 and 0.020 respectively). Among AN (but not controls), reductions in ghrelin and increases in PYY in the first 30-minutes following breakfast were associated with reductions in VAS scores for prospective food consumption. AN consumed fewer calories during the CTT vs. controls (p < 0.0001). In AN (particularly AN-restrictive subtype), BDNF AUC was positively associated with kilocalories consumed during the CTT Conclusions: In young females with AN, changes in ghrelin and PYY following food intake are associated with reductions in a prospective measure of food consumption, while reductions in BDNF are associated with reduced hedonic food intake. Further studies are necessary to better understand the complex interplay between appetite signals and eating behaviors in AN.