Concurrent and prognostic utility of subtyping anorexia nervosa along dietary and negative affect dimensions

Bulimia nervosa can be reliably classified into subtypes based on dimensions of dietary restraint and negative affect. Community and clinical studies have shown that dietary-negative affect subtypes have greater test-retest reliability and concurrent and predictive validity compared to subtypes based on the Diagnostic and Statistical Manual of Mental Disorders (DSM). Although dietary-negative affect subtypes have shown utility for characterizing eating disorders that involve binge eating, this framework may have broader implications for understanding restrictive eating disorders.

The purpose of this study was to test the concurrent and predictive validity of dietary-negative affect subtypes among patients with anorexia nervosa (AN; N = 194).

Latent profile analysis was used to identify subtypes of AN based on dimensions of dietary restraint and negative affect. Chi-square and multivariate analysis of variance were used to characterize baseline differences between identified subtypes. Structural equation modeling was used to test whether dietary-negative affect subtypes would outperform DSM categories in predicting clinically relevant outcomes.

Results supported a 2-profile model that replicated dietary-negative affect subtypes: Latent Profile 1 (n = 68) had clinically elevated scores on restraint only; Latent Profile 2 (n = 126) had elevated scores on both restraint and negative affect. Validation analyses showed that membership in the dietary-negative affect profile was associated with greater lifetime psychiatric comorbidity and psychosocial impairment compared to the dietary class. Dietary-negative affect subtypes only outperformed DSM categories in predicting quality-of-life impairment at 1-year follow-up.

Findings highlight the clinical utility of subtyping AN based on dietary restraint and negative affect for informing future treatment-matching or personalized medicine strategies. (PsycINFO Database Record