Triggers for eating disorder onset in youth with anorexia nervosa across the weight spectrum.

To aid in more targeted eating disorder (ED) prevention efforts, we sought to identify sociodemographic and weight-related risk factors for identified triggers for the onset of anorexia nervosa (AN) in youth. We conducted a retrospective chart review of youth admitted for medical treatment of AN between January 2015 and February 2020. From multidisciplinary admission notes, we extracted patient-reported reasons for diet/exercise changes. We used qualitative thematic analysis to identify ED triggers, then categorized each trigger as binary variables (presence/absence) for logistic regression analysis of risks associated with each trigger. Of 150 patients, mean (SD) age was 14.1(2.3) years. A total of 129 (86%) were female and 120 (80%) were Non-Hispanic White. Triggers included environmental stressors (reported by 30%), external pressures of the thin/fit ideal (29%), internalized thin/fit ideal (29%), weight-related teasing (19%), and receiving health education (14%). Younger age was associated with higher odds of weight-related teasing (p = .04) and health education (p = .03). Males had greater odds of internalized thin/fit ideal than females (p = .04). Those with premorbid body mass indices ≥85th percentile for age and sex had greater odds of reporting positive reinforcement (p = .03) and weight-related teasing (p = .04) than those with weights <85th percentile. We use these findings to detail potential targets for advancing ED prevention efforts.