DSM-IV-defined anorexia nervosa versus subthreshold anorexia nervosa (EDNOS-AN)

Eating disorder not otherwise specified (EDNOS) is the most prevalent eating disorder, yet its heterogeneity begs less reliance on this broad diagnostic category. The purpose of this study was to compare women with anorexia nervosa (AN) and EDNOS, AN type (EDNOS-AN) from a multisite study on eating-related and general psychopathology measures.

One hundred eighteen participants (n = 59 with DSM-IV AN, n = 59 with EDNOS-AN) completed structured interviews, questionnaires and a physical examination at baseline. In addition, participants carried a handheld palm pilot computer for 2 weeks to provide ecological momentary assessment (EMA) information about mood and eating disorder behaviours.

No significant differences between AN and EDNOS-AN were found on the self-report and interview measures, or on the EMA mood assessments. The only differences to emerge were that participants with AN reported higher rates of binge eating and purging on EMA compared with those with EDNOS-AN, whereas EDNOS-AN reported higher rates of checking thighs and joints on EMA compared with those with AN. For the physiological parameters, AN presented with lower white blood cell counts compared with EDNOS-AN.

Findings highlight the clinical significance of EDNOS-AN and support a closer look at the definition of AN as proposed by the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition.