Disaggregating the predictive effects of impaired psychosocial functioning on future DSM-5 eating disorder onset in high-risk female adolescents.

OBJECTIVE: Impaired psychosocial functioning previously emerged as the only risk factor to predict future onset of each of the four Diagnostic and Statistical Manual of Mental Disorder (5th ed.) (DSM-5) eating disorders. The goal of this follow-up report was to refine understanding of this newly identified risk factor.
METHOD: Combining data from women at risk for eating disorders because of body image concerns (N = 1,153, mean age = 18.5 years, SD = 4.2), we investigated which subdomain(s) and individual item(s) of psychosocial functioning (friends, family, school, and work) at baseline predicted onset of any eating disorder, using Cox regression (CRA) and classification tree analysis (CTA).
RESULTS: Psychosocial impairment with friends, family, and at school, but not at work, significantly increased risk for disorder onset over 3-year follow-up in univariate models. A one-unit increase in each domain raw score was associated with a 107, 22, and 43% increased hazard of eating disorder onset, respectively. Multivariate CRA found friends functioning, with a 92% increased hazard of disorder onset, contributed the strongest unique effect. CTA suggested that loneliness was the most potent risk factor with a threefold increased onset risk (eating disorder incidence for high vs. low scorers was 27 and 8%). Three friends functioning items and one school functioning item produced additional CTA branches. DISCUSSION: Results refine understanding of the relation of psychosocial impairment to future onset of eating disorders, suggesting that peer functioning is the most critical. Data imply it would be useful to target young women with impaired psychosocial functioning in prevention programs.