Dietary and dietary-depressive subtypes of bulimia nervosa show differential symptom presentation, social impairment, comorbidity, and course of illness.

Research suggests that women with bulimia nervosa can be classified into dietary and dietary-depressive subtypes and that the latter show greater eating pathology, social impairment, comorbidity, and treatment nonresponse. The authors sought to replicate this subtyping scheme with an independent sample and to generate further evidence for the validity of this distinction. Analysis revealed dietary and dietary-depressive subtypes and indicated that the latter reported more current eating pathology, social impairment, and treatment seeking as well as greater psychiatric comorbidity and bulimic symptom persistence over a 5-year follow-up. This subtyping scheme had stronger concurrent and predictive validity than the purging-nonpurging distinction. Results provide further evidence for the reliability and validity of this subtyping scheme and suggest it has important clinical implications.