A prospective test of the temporal sequencing of risk factor emergence in the dual pathway model of eating disorders.

Prospective studies have identified risk factors that predict future onset of eating disorders, but none has provided a test of the temporal sequencing of the emergence of risk factors hypothesized in a multivariate etiologic model of eating disorder development. Using data from an 8-year prospective study of 496 adolescent girls, we first conducted receiver operator characteristic plots to identify cut-points for each risk factor that optimally predicted future onset of threshold or subthreshold bulimia nervosa, binge eating disorder, and purging disorder. We then used growth curve models to estimate the age at which each participant crossed the disorder-predictive cutpoint for each risk factor, or if they did not, during follow-up, permitting a test of whether the risk factors emerged in the sequence hypothesized in the Dual Pathway etiologic model. Overall, 47% of the 51 youth who showed onset of one of these eating disorders first showed emergence of disorder-predictive levels of perceived pressure to be thin and/or thin-ideal internalization, before showing onset of disorder-predictive levels of body dissatisfaction, before showing onset of disorder-predictive levels of dieting and/or negative affect, before showing onset of the eating disorder; another 29% had one of these steps out of order or did not cross one step in this model. Youth who did not show onset of an eating disorder were significantly less likely to cross the disorder-predictive cut-points for each risk factor or to conform to the sequence of risk factor emergence hypothesized in this model. Results provide novel support for the temporal sequencing of risk factor emergence hypothesized in this multivariate etiologic model and suggest that prevention programs that reduce perceived pressure to be thin and thin-ideal internalization among early adolescent girls with these factors should reduce eating disorder onset, as well as downstream risk factors that are also aversive (e.g., body dissatisfaction and negative affect). (PsycINFO Database Record (c) 2018 APA, all rights reserved).