Early Course of Symptom Development in Anorexia Nervosa

Anorexia nervosa (AN) commonly begins in adolescence; however, detailed knowledge of symptom trajectories, including their temporal sequence, is less well elucidated. The purpose of the present study is to describe the onset and duration of disordered eating behaviors prior to a diagnosis of AN, examine concordance between child and parent report, and examine the relationships between timing of symptom onset and illness severity.

Seventy-one adolescents (ages 12-18 years) and their parents were interviewed about dieting, restriction, loss of control/binge eating, purging, excessive/compulsive exercise, weight history, and amenorrhea. Body mass index percentiles were calculated, and adolescents completed the Eating Disorder Examination-Questionnaire.

Restriction, being underweight, dieting, and excessive exercise were reported by most of the sample; purging, loss-of-control eating, and having been overweight were reported by less than a third. Dieting typically emerged first, on average around age 14; the remainder of behaviors tended to emerge between ages 14 and 14½; and average age of formal diagnosis was slightly over 15 years. Dyads had good agreement regarding presence and timing of all behaviors except for dieting, for which children reported about 6 months earlier onset/longer duration, compared to parents. Although older age at interview was associated with lower body mass index percentile and higher EDE-Q score, neither age of onset nor duration was associated with severity when controlling for current age.

Teens and parents describe a similar sequence of behavior changes leading up to a diagnosis of AN that typically begins with dieting and occurs over an approximate 1- to 1½-year period. Querying teens and parents about eating behavior changes may aid in identification and early intervention in AN; adolescents with normal weight who engage in persistent dieting or restrictive eating may warrant more frequent weight monitoring.