Only 2 eating disorders, anorexia nervosa and bulimia, are uniquely described within DSM criteria. “For everybody else – and there are a lot of everybody elses – there's EDNOS; Eating Disorder Not Otherwise Specified,” said Evelyn Attia, MD, Columbia University Center for Eating Disorders, New York, NY (Figure 1).

Epidemiological data from a recent community-based study of over 9000 individuals indicated that the lifetime prevalences of eating disorders for women are anorexia 0.9%, bulimia 1.5%, and binge eating disorders 3.5% (with much lower rates for men, overall). The survey also found that the majority never seeks treatment [Hudson et al. Biol Psych 2007]. What about those who do seek treatment? “We have a bit of a predicament with this because as many as 60% does not meet the full criteria for anorexia or bulimia nervosa.”

Little progress has been made in the area of treatment options for eating disorders, though promise is seen in the family-based Maudsley Intervention. Contrary to traditional clinical recommendations of “parentectomy,” the parents are put in charge of the re-feeding process and draw on their creative resources and strengths to move the child toward health.

There are no new medications for anorexia, per se, and past results have been mixed. The atypical antipsychotic, olanzapine, is the subject of some interest. “Some patients gain weight,” said Dr. Attia, “but we have a hard time convincing them to try it or remain on it.”

Good results can be seen with cognitive behavioral therapy for bulimia as well as with antidepressants, such as fluoxetine. “Of interest here is how patients respond [to fluoxetine] and when they respond.” The effect will be seen in the first 2 weeks of treatment if it's going to be seen at all.

Patients with Binge Eating Disorder have several symptoms that need to be addressed through treatment. There are somatic issues, such as obesity management; behavioral issues, as in the cessation of binging; and psychological issues, such as stress reduction and self-acceptance. For this group, a whole range of medications have been tried. “Many seem to fare better than placebo when it comes to binge frequency,” said Dr. Attia, “but response to placebo also is quite high.” As for treating weight loss in these patients, it's essential to keep in mind that binge eating is a separate disorder from overeating.

To date, there have not been many studies that address EDNOS. A single study of Night Eating Disorder suggests that sertraline might be effective [O'Reardon et al. Am J Psych 2006], and there is an ongoing trial that is investigating fluoxetine for Purging Disorder.