Diagnostic crossover in eating disorders

I know I've written several posts about the diagnostic criteria of eating disorders. It's a hot topic of debate as the new DSM-V undergoes revisions for a variety of disorders. I came across this article from a few months ago which looked at the crossover rate in eating disorders. By crossover, this mean changing from an anorexia to bulimia diagnosis and vice versa.

This longitudinal study consisted of 216 woman with anorexia, anorexia subtypes of restricting or binge/purge, and bulimia over a period of 7 years. The average duration of illness was 6 years among the women. Based on symptomology, each were assessed weekly with a diagnosis.

The results indicated that almost three-quarters of the patients with anorexia crossed over, about half of that number switched within the anorexia subtype, almost one tihrd crossed over to bulimia, leaving a small number who did not cross over at all. Of those with a diagnosis of anorexia restricting type, a little over half crossed over into either binge/purge type anorexia or bulimia. Those with an initial diagnosis of bulimia had a much lower rate of crossing over. The small minority that experienced this changed to binge/purge type anorexia.

Besides the diagnostic changes, results also indicated that a significant number from each group had partial recovery. Those reaching full recovery was higher for the bulimia group versus the anorexia group, including subtypes. In about half of those with anorexia who crossed over to bulimia, happened while obtaining partial or full recovery. This could indicate that it isn't really a change in disorder so much as a stage in illness. The other half of anorexics who crossed over to bulimia crossed back to anorexia which could indicate that those with a lifetime history of anorexia are more prone to relapse into anorexia.

Essentially, this study shows the frequency of cross over between anorexia, its subtype, and bulimia. This questions the validity of having anorexia subtypes in the first place. It seems that it is not likely a change of disorders, but rather a more apparent of stage of illness. I should note that this study did not look at non-purging bulimics nor EDNOS as it was not recognized in the DSM at that time.

I thought this was an interesting study overall. The fact that it was longitudinal was very helpful in showing how so many individuals flip flop back and forth between anorexia and bulimia. It was also sobering that many reached partial recovery and a good number full recovery. In general, this study implicates further the need for better diagnostics for eating disorders. I hope the DSM-V will provide that.

study abstract
If you go to the full text, you can download it for free. The graphs shown give a better idea of the frequency of cross over and recovery rates.

Eating disorder diagnostic criteria investigated

Will diagnostic criteria for eating disorders change?
According to this new study out of Rhode Island hospital and Brown University, researchers found that the majority of eating disorder individuals fell into the category of "EDNOS" or eating disorder not otherwise specified. This essentially means that these individuals did not fall strictly into the categories of anorexia or bulimia defined by the DSM-IV-TR.

This really doesn't surprise me at all. Experts have debated for years about the official criteria for eating disorders. Many have said it needed to be changed and the definition broadened as this study shows. I read awhile back that some eating disorder experts have suggested the removal of the "amenorrhea" criteria in anorexia for the new DSM-V, set to be published tentatively in 2012. In many cases, amenorrhea has been shown not to be that reliable of an indicator for anorexia. In this archived article from The New York Times, there is wide discussion about the "future of EDNOS." It will also be interesting to see whether other new subtypes will be considered such as "purging" disorder which made news back in September 2007 by Dr. Keel from University of Iowa.

Authors are even weighing in on naming and labeling, including Aimee Liu. On her website, she is actually having a naming contest asking people to think of a new name for "eating disorder." She will then address the Academy for Eating Disorders for "official" consideration.

If you speak to those with eating disorders, many get upset about the whole diagnostic criteria for eating disorders feeling that it's basically just a "label" and should not matter. Others feel that without an official diagnosis, their illness is not validated. Unfortunately, insurance companies want a label. To them, that label is important. It gives them the power to say what coverage they can allow whether or not it is actually sufficient for your treatment. Further, without a pure recognized "biological" basis, many insurance companies will not cover as much for treatment. Researchers are gaining ground on this area, but it has a long way to go. Many states have some form of a mental health parity law, but it varies state to state. This site gives a nice rundown of each state.

Whew, lots of information there. I went a little off tangent, but all of this relates to one another vastly as these are the issues of today.