Obesity Rejected as Psychiatric Diagnosis in DSM-5

Neither obesity nor simple overeating will be included in the DSM-5, the forthcoming revision to the Diagnostic and Statistical Manual of Mental Diseases, but binge eating is on track to become a formal psychiatric diagnosis, it was reported here.

The addition of binge eating is one of several changes within the eating disorders category in the DSM, according to B. Timothy Walsh, MD, of Columbia University in New York City, head of the DSM-5 work group in this clinical area.

But, said Walsh in a report here at the American Psychiatric Association's (APA) annual meeting, he and his colleagues did not believe there was enough hard evidence to support creating a psychiatric diagnosis for obesity or overeating.

"We don't have the data to merit anything beyond binge eating," he said. "We have to follow the field, not lead it."

But he held out the possibility that some kind of overeating syndrome, distinct from binge eating, might be added in the future. "I would not dismiss the theoretical basis" for considering overeating a psychiatric condition, he said.

Darrel Regier, MD, MPH, the APA's research director, commented that a number of studies have suggested that people who eat excessively have biological similarities, in terms of neural firing patterns, to those with substance addictions.

Trimming EDNOS

Walsh told attendees that the eating disorders category had cried out for an overhaul. The current edition of the DSM lists just three types for adults: anorexia, bulimia, and eating disorders not otherwise specified (EDNOS).

Studies reviewed by the work group suggested that up to 45% of all patients treated for eating disorders receive a diagnosis of EDNOS, an indication that the current classifications are inadequate.

Three additional diagnoses were initially proposed to take patients out of EDNOS, Walsh said. In addition to binge eating disorder, these were purging disorder and night eating syndrome.

Purging disorder would have covered patients with bulimia symptoms but without any abnormal eating habits. Night eating syndrome was intended for patients who get up in the night to eat an extra meal, but who wouldn't qualify as binge eaters.

In the end, according to Walsh, the work group decided that these would be premature. They may be included in an appendix to the DSM-5, a sort of holding tank for symptom bundles that need more study before acceptance as officially recognized disorders.

Indeed, binge eating is in the appendix of the current DSM.

Defining Binge Eating

Criteria for diagnosing binge eating disorder will be tested in field trials set to begin this summer.

The primary definition is that patients eat amounts at one sitting that are "definitely larger than most people would eat in a similar period of time under similar circumstances," and the patient must also perceive a lack of control over the amount eaten.