Investigating the DSM-5 severity specifiers based on thinness for adults with anorexia nervosa

The DSM-5 severity classification scheme for adults with anorexia nervosa (AN) is based upon current body mass index (BMI; kg/m² ). This study examined the utility of the DSM-5 severity specifiers for adults with AN in relation to core cognitive and behavioral features of eating pathology and associated psychosocial impairment.

A clinical sample of 146 adult AN patients (140 women, 6 men) were categorized using DSM-5 current BMI severity specifiers and assessed with the Eating Disorder Examination-Questionnaire (EDE-Q) and Clinical Impairment Assessment (CIA).

A total of 34 (23.3%) patients were categorized as mild (>=17.0 BMI), 35 (24.0%) as moderate (16-16.99 BMI), 32 (21.9%) as severe (15-15.99 BMI), and 45 (30.8%) as extreme (<15 BMI). No significant group differences were found for age, CIA and EDE-Q global or subscale scores, frequency of laxative use, self-induced vomiting, binge eating, or excessive exercise.

This study found little empirical evidence to support the utility of DSM-5 severity rating scheme to differentiate adults with AN in terms of core eating disorder pathology or associated psychosocial impairment.