Risk factors for binge eating and purging eating disorders: differences based on age of onset

OBJECTIVE: To (1) determine whether childhood risk factors for early onset binge eating and purging eating disorders also predict risk for later-onset binge eating and purging disorders, and (2) compare the utility of childhood and early adolescent variables in predicting later-onset disorders.

METHOD: Participants (N = 1,383) were drawn from the Western Australian Pregnancy Cohort (Raine) Study, which has followed children from pre-birth to age 20. Eating disorders were assessed when participants were aged 14, 17, and 20. Risk factors for early onset eating disorders have been reported previously (Allen et al., J Am Acad Child Psychiat, 48, 800-809, 2009). This study used logistic regression to determine whether childhood risk factors for early onset disorders, as previously identified, would also predict risk for later-onset disorders (n = 145). Early adolescent predictors of later-onset disorders were also examined.

RESULTS: Consistent with early onset cases, female sex and parent-perceived child overweight at age 10 were significant multivariate predictors of binge eating and purging disorders with onset in later adolescence. Eating, weight, and shape concerns at age 14 were also significant in predicting later-onset disorders. In the final stepwise multivariate model, female sex and eating, weight, and shape concerns at age 14 were significant in predicting later-onset eating disorders, while parent-perceived child overweight at age 10 was not.

DISCUSSION: There is overlap between risk factors for binge eating and purging disorders with early and later onset. However, childhood exposures may be more important for early than later onset cases.