DENVER -- Look for fine-tuning rather than major upheavals in the revised eating disorders categorization system to be included in the next edition of the Diagnostic and Statistical Manual of Mental Disorders, Dr. B. Timothy Walsh predicted at an international conference of the Academy for Eating Disorders.
He offered a former insider's view on the strengths and weaknesses of the eating disorders section of the DSM-IV, as well as speculation about the changes likely to lie ahead for the DSM-V. He stressed, however, that he was presenting personal opinion only--although he chaired the committee that wrote the eating disorders section of the DSM-IV, he is not involved in planning the DSM-V.
"Looking ahead to the DSM-V, I would suggest retaining the same basic structure as now. You don't go around making a radical change in a system real fast unless you're really, really sure it's going to have superior clinical utility to what we've got now. The historical constraint, as we worked through the DSM-IV, was impressively powerful. It immediately makes you cautious about doing things," explained Dr. Walsh, the Ruane Professor of Pediatric Psychopharmacology at Columbia University, New York.
The DSM-IV was evidence-based. Presumably the DSM-V will be, too. And the primary goal of the DSM system is providing clinical utility rather than facilitating research.
"The real push behind the categorization in DSM is to make it useful for clinicians. In the discussions on DSM-IV the trump was always, 'What's clinically useful?' That's the driving principle behind what I'll certainly admit are some peculiar decisions," said Dr. Walsh, who also serves as director of the eating disorders research unit at the New York State Psychiatric Institute.
"I'm not saying this categorization is the best, I'm not saying it's the only. But it does end up quickly transmitting some clinically useful information about course and outcome of an illness, complications, and appropriate treatment. For example, when I hear 'anorexia nervosa,' I'm thinking I might want to consider hospitalization, I know weight restoration is going to be a primary treatment goal, meds probably aren't going to help, this person has got major medical risk, and there's high mortality," he continued.
Similarly, the diagnostic label "bulimia nervosa" implies outpatient management, a high likelihood that weight is normal, and the availability of several effective forms of psychotherapy and medication. The label "binge eating disorder," in contrast, implies obesity is likely, and a wide range of interventions is useful, he noted at the conference, which was sponsored by the University of New Mexico.
Here are some key areas where Dr. Walsh thinks the DSM-V diagnosis of eating disorders is likely to change--and equally important, areas likely to remain the same as in the DSM-IV:
* Anorexia nervosa. The biggest change that the DSM-IV brought about in the categorization of this disorder was inclusion of a subtyping scheme separating patients into restricting versus bingeing/purging subtypes. The validity of the move to subtyping has generally been supported by the roughly 16 studies that have examined the issue since the DSM-IV came out. The data indicate that patients with the restricting subtype of anorexia nervosa are younger, have a shorter duration of illness, attain lower weights, are less impulsive, and have less comorbid psychopathology. So anorexia nervosa subtyping is probably here to stay.
The DSM-V may provide a good opportunity to eliminate the amenorrhea requirement in anorexia nervosa.
The half-dozen or so studies that have looked at this issue have consistently found that the clinical characteristics of women who meet the other criteria but aren't amenorrheic are quite similar to those who are, Dr. Walsh continued.
Fear of fatness is another current diagnostic criterion that needs to be revisited. …