Researchers Lay Out Challenges Facing Developers of DSM-V

“Good morning to all on DSM-V territory!” David Goldberg, M.D., of the Institute of Psychiatry at King's College, London, breezily announced on March 5.

In truth, it was the Crowne Plaza Hotel in New York City. But figuratively it was “DSM-V territory” since he and other psychiatric scientists were there to address the framework of the next edition of the world-famous Diagnostic and Statistical Manual of Mental Disorders (DSM).

Moreover, the three-day symposium, sponsored by the American Psychopathological Association and attended by about 100 psychiatric scientists, underscored some of the challenging conceptual questions facing the experts who are crafting the fifth edition of the 57-year-old DSM. (In fact, all of the scientists who spoke at the symposium are involved in the development of DSM-V.)

First, what is a mental disorder? Is it symptoms? disease? functional disability? Should variants in behavior be considered disorders, and if so, how much variation? There are no simple answers to this question, Norman Sartorius, M.D., Ph.D., a past director of the World Health Organization's Division of Mental Health, indicated.

Furthermore, “We are still focused on similarities of symptoms, signs, and course rather than underlying principles,” said Steven Hyman, M.D., a former director of the National Institute of Mental Health and currently provost of Harvard University, because the causes of most mental disorders, with a few exceptions, are not yet clear. Hyman is a member of the DSM-V Task Force.

Hyman also noted that with the rapid advances in psychiatric genetics, the processes underlying various mental disorders seem to be becoming more rather than less complex. For example, while certain genes appear to underlie bipolar disorder, and others to underlie schizophrenia, a number of the same genes show strong links to both conditions, a recent study revealed.

So what will the definition of a mental disorder in DSM-V be?“ It has not been determined yet,” Darrel Regier, M.D., vice chair of the DSM-V Task Force, avowed. “It is an imprecise art coming to such a definition.” Regier is also director of research at APA, executive director of the American Psychiatric Institute for Research and Education, and president of the American Psychopathological Association.

Use Categories or Dimensions?

Yet if mental disorders end up being classified essentially on the basis of symptoms, should those symptoms be categorized, or should they be presented in a dimensional manner, or perhaps both (See Original article: Taking Symptoms to New Dimensions)?

“I think simultaneous use of both methods can provide information that either alone cannot provide,” said Ellen Frank, Ph.D., of the University of Pittsburgh Department of Psychiatry.

Regier indicated that he too would like to see dimensions added to the categorization of mental disorders. So did John Helzer, M.D., a professor of psychiatry at the University of Vermont. “DSM-V is certainly going to be a top-down categorical system,” as it has been in the past, he predicted, but using simple scales to determine whether patients' symptoms are mild, moderate, or severe would enhance the accuracy of various diagnoses, he suggested.

How to manage the dimensional with the categorical “promises to be one of the more revolutionary aspects of DSM-V,” Wilson Compton, M.D., of the National Institute on Drug Abuse and a member of the DSM-V Task Force, stated.

Also pressing is the question of how mental disorders should be grouped in DSM-V, that is, on the basis of similar symptoms, signs, and course or on the basis of similar origins? Hyman favors the latter. True, the genes underlying most mental disorders seem to be incredibly complex, he conceded, and thus grouping disorders on the basis of genetic origin is out of the question at this point. But another possibility, he said, might be to group mental disorders on the basis of “shared neural circuits.” For instance, both human and rodent studies have shown that the amygdala is hyperactive in various types of anxiety disorders. So mental disorders that involve an overly vigilant amygdala might be grouped together in DSM-V.

Race “Messes Up Your Models”

What about the impact of culture, race, and gender on psychiatric disorders? Should DSM-V take them into consideration? Certainly, James Jackson, Ph.D., a social scientist at the University of Michigan Institute for Social Research and a member of a DSM-V work group, indicated. Yet he admitted that the subject is “complex.” For example, he and his colleagues found, in some 25,000 American subjects, not only that race influenced the prevalence of mood disorders, but that its influence was modified by factors such as gender and whether a person had immigrated to the United States, and at what age.

In brief, as a social scientist, “Race really messes up your models!” Jackson asserted, which brought some chuckles from the audience.

Then there is a related vexing question: Should DSM-V take note of the impact of life development on mental disorders? Although it has been known for years that clinical presentations change with age, the evidence that this is the case has been growing increasingly robust of late, Daniel Pine, M.D., an anxiety disorder specialist at the National Institute of Mental Health and chair of a DSM-V work group, observed. For instance, one study tracked some 700 children with anxiety problems and found that while most of these problems were transient, a minority were not. Thus, “I would like a clearer recognition in DSM-V [than in DSM-IV] that a diagnosis is only a snapshot in time, and if we can do that, it will be a big step forward,” Pine said.

But the dilemma is how to include information of this nature in DSM-V. A possible solution, Pine said, might be to introduce a new feature—an age-related expression of the same symptoms for a disorder. For example, the symptoms of attention-deficit/hyperactivity disorder (ADHD) express themselves in children differently from in adults.

Another possibility, he said, might be to include developmental norms for each disorder—say, that irritability in children may reflect depression or that adolescents with ADHD tend to be less hyperactive than younger children with the disorder.

Finally, DSM is used by an incredible range of people, William Narrow, M.D., associate director of APA's Office of Research and director of research for DSM-V, pointed out—for example, at the National Institutes of Health, the Food and Drug Administration, and the Social Security Administration; in the health insurance industry and the legal system; and on Capitol Hill. But DSM is, and should remain, first and foremost a clinical tool, he maintained.

Certainly this symposium was not the first to address the paradigm of DSM-V, nor will it be the last, since work on the next edition started a decade ago and is expected to continue until the edition's publication in 2012, Regier stressed. Summing up the goal of the meeting, he said that “the challenge is to conserve the wisdom of our predecessors, but to also be astute about some new developments.” ▪