From the New York Times:
Proposed changes in the definition of autism would sharply reduce the skyrocketing rate at which the disorder is diagnosed and may make it harder for many people who would no longer meet the criteria to get health, educational and social services, a new analysis suggests.
The definition is under review by an expert panel appointed by the American Psychiatric Association, which is completing work on the fifth edition of its Diagnostic and Statistical Manual of Mental Disorders. The D.S.M, as the manual is known, is the standard reference for mental disorders, driving research, treatment and insurance decisions.
The study results, presented on Thursday at a meeting of the Icelandic Medical Association, are still preliminary, but they offer the latest and most dramatic estimate of how tightening the criteria for autism could affect the rate of diagnosis. Rates of autism and related disorders like Asperger syndrome have taken off since the early 1980s, to prevalence rates as high as one in 100 children in some places. Many researchers suspect that these numbers are inflated because of vagueness in the current criteria.
“The proposed changes would put an end to the autism epidemic,” said Dr. Fred R. Volkmar, director of the Child Study Center at Yale University School of Medicine and an author of the new analysis. “We would nip it in the bud — think of it that way.”
Experts working on the new definition strongly questioned the new estimate. “I don’t know how they’re getting those numbers,” said Catherine Lord, a member of the task force working on the diagnosis.
I have no idea what to make of any of this.
I have long wondered if the dramatic rise in autism diagnoses, which has in turn helped fuel anti-vaccine hysteria, was related to vagueness in the diagnostic criteria, and whether other disorders might better account for the symptoms of many patients labeled as having an autism spectrum disorder (ASD). Developmental pediatrics is not my specialty, however, and so I’m reluctant to pronounce with any authority on the subject. The senior partner in my office is board-certified in developmental pediatrics, to which his practice is almost entirely limited at this point. From what I’ve informally observed after reading a good number of his evaluations, he is very careful about distinguishing an ASD from another diagnosis that may be more appropriate, such as an anxiety disorder or obsessive-compulsive behaviors.
Looking at the “before” and “after” criteria, I’ll admit to being a bit perplexed as to what changes are so monumental as to “put an end to the autism epidemic.” Here they are before and after. (The criteria are lengthy, and do not lend themselves to being inserted in toto.) The new guidelines are more streamlined, and in order to make the diagnosis more of them must be present. The only change that seems particularly stringent is this last one:
D. Symptoms together limit and impair everyday functioning.
There is no mention of everyday functioning in the old criteria.
Because the study is preliminary, and the results were presented at a meeting rather than in published form, I cannot look at its methodology and get a sense of whether it was well conducted. As such, I’m reluctant to come to any particular conclusion. If I were to speculate, I would guess that those who might be excluded from an ASD diagnosis are those on the less severe side, whose degree of impairment is milder and whose diagnosis may have been less clear. Conversely, I have a hard time imagining a scenario where a moderately or severely affected individual would meet the criteria from before but not now.
If these new criteria streamline and clarify the diagnosis of autism, then I am tentatively in favor. It does rather raise the question of how genuine a phenomenon the autism epidemic was in the first place, however, and whether the hype and anxiety were ever justified.