Eating Disorder Not Otherwise Specified

Eating Disorder Not Otherwise Specified

Eating disorder not otherwise specified (EDNOS) is an eating disorder that does not meet the criteria for any specific eating disorder. Thus, individuals who have clinically significant eating disorders that do not meet DSM-IV criteria for anorexia nervosa or bulimia nervosa are diagnosed with EDNOS. Individuals with EDNOS usually fall into one of three groups: subthreshold symptoms of anorexia nervosa or bulimia nervosa, mixed features of both disorders, or extremely atypical eating behaviors that are not characterized by either of the other established disorders. In other words, EDNOS acts as a default category, and is defined by what it is not. Currently, EDNOS is the most commonly diagnosed eating disorder in clinical settings. Because little is known about the symptoms, course, and outcome of this heterogeneous category, the preponderance of EDNOS in clinical practice impedes clinical communication, treatment planning, epidemiological inquiry, primary prevention, and basic research.

As EDNOS was initially thought to be rare, and as 5 of the 6 proposed DSM-5 EDNOS presentations are well-defined, it seems likely that the "residual" (undefined) presentation accounts for most of the 40% of Eating Disorder cases diagnosed as EDNOS. Research is required into how many of these "residual" EDNOS diagnoses were eventually replaced by that of a recognised medical condition, whether psychologically or organically caused. While all organic causes should be ruled out prior to making a diagnosis of an eating disorder, in practice this is difficult as many physical conditions can also result in low weight, and may develop over time.