「自閉症」の定義

BENEDICT CAREY “New Definition of Autism Will Exclude Many, Study Suggests” http://www.nytimes.com/2012/01/20/health/research/new-autism-definition-would-exclude-many-study-suggests.html

米国精神医学会（American Psychiatric Association）ではDiagnostic and Statistical Manual of Mental Disorders(D. S. M.)の17年ぶりの改訂を進めている。その中で特に話題になっているのは「自閉症（autism）」の定義について。

(…) The revisions are about 90 percent complete and will be final by December, according to Dr. David J. Kupfer, a professor of psychiatry at the University of Pittsburgh and chairman of the task force making the revisions.

At least a million children and adults have a diagnosis of autism or a related disorder, like Asperger syndrome or “pervasive developmental disorder, not otherwise specified,” also known as P.D.D.-N.O.S. People with Asperger’s or P.D.D.-N.O.S. endure some of the same social struggles as those with autism but do not meet the definition for the full-blown version. The proposed change would consolidate all three diagnoses under one category, autism spectrum disorder, eliminating Asperger syndrome and P.D.D.-N.O.S. from the manual. Under the current criteria, a person can qualify for the diagnosis by exhibiting 6 or more of 12 behaviors; under the proposed definition, the person would have to exhibit 3 deficits in social interaction and communication and at least 2 repetitive behaviors, a much narrower menu.

Dr. Kupfer said the changes were an attempt to clarify these variations and put them under one name. Some advocates have been concerned about the proposed changes.

今回の改訂は「自閉症」の定義を狭くするもので、これによって「自閉症」と診断される人は大幅に減少することになる；

In the new analysis, Dr. Volkmar, along with Brian Reichow and James McPartland, both at Yale, used data from a large 1993 study that served as the basis for the current criteria. They focused on 372 children and adults who were among the highest functioning and found that overall, only 45 percent of them would qualify for the proposed autism spectrum diagnosis now under review.

The focus on a high-functioning group may have slightly exaggerated that percentage, the authors acknowledge. The likelihood of being left out under the new definition depended on the original diagnosis: about a quarter of those identified with classic autism in 1993 would not be so identified under the proposed criteria; about three-quarters of those with Asperger syndrome would not qualify; and 85 percent of those with P.D.D.-N.O.S. would not.

Dr. Volkmar presented the preliminary findings on Thursday. The researchers will publish a broader analysis, based on a larger and more representative sample of 1,000 cases, later this year. Dr. Volkmar said that although the proposed diagnosis would be for disorders on a spectrum and implies a broader net, it focuses tightly on “classically autistic” children on the more severe end of the scale. “The major impact here is on the more cognitively able,” he said.

当事者たちが懸念しているのは今まで「自閉症」と診断されていたが故に享受してきた福祉的な保護が取り消されるのではないかということ。
また「自閉症」の人にとって「自閉症」というのはそもそも外部から押しつけられたものではあるけど、時間の経過とともにそれは自己のアイデンティティの一部を構成するようになり、それによって世界の中の〈居場所〉も得ている筈なのだ。それが、外部の都合によって再度剥奪されるというのはどういうことなのか。
D. S. M.の改訂は米国以外に対する影響も大きいのだろう。
「自閉症」についてはhttp://d.hatena.ne.jp/sumita-m/20070305/1173111662 http://d.hatena.ne.jp/sumita-m/20090916/1253070929 http://d.hatena.ne.jp/sumita-m/20091106/1257535198 http://d.hatena.ne.jp/sumita-m/20101211/1292091136でも言及している。「自閉症」の定義の困難さについて、以前も引用したオリヴァー･サックスの

自閉症は誰ひとりとして同じではない。病態や現われ方はすべてちがう。しかも、自閉症的特性とその他の個人的資質には、創造的可能性をうかがわせる不思議な相互作用があるらしい。したがって、臨床的所見のためなら一瞥すれば充分であるにしても、ほんとうに自閉症の個人を理解しようとすれば、全生涯を見つめなければ足りないだろう。（「火星の人類学者」、p.339）

というパッセージを再度提示しておく。

火星の人類学者―脳神経科医と7人の奇妙な患者 (ハヤカワ文庫NF)