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Scientists blame autism
'epidemic' on new diagnosis
By David Derbyshire, Science Correspondent
(Filed: 06/09/2002)
Much of
the "autism epidemic" sweeping the West simply reflects a broader
diagnosis of the condition, a Telegraph poll of 52 academics and doctors
suggests.
Thirty years ago, children who had problems with
communication, social interaction, imagination and repetitive behaviour
were likely to be described as "schizo-obsessive" or even "retarded".
Today, they are usually diagnosed with an autism spectrum disorder.
Prof Eric Hollander, a psychiatrist and clinical
director of the Seaver Centre for Autism research at Mount Sinai School
of Medicine, New York, said: "Many of the people with milder forms used
to slip through the cracks because they did not have the profound speech
problems or mental retardation problems. In the old days we would have
seen these people in adolescence because they would not have been coping
socially."
Prof Hollander said many of them would have been
labelled schizo-obsessive, mentally retarded or having a schizo-type
personality.
He said he did not think the measles, mumps and rubella
vaccine was affecting the number of children with autism.
"I think much of the increase is to do with increased
awareness and more comprehensive detection," he said. "But you cannot
fully rule out some increase in incidence. There are things in the
environment that could theoretically be playing a role."
His own research is investigating the interaction of
genetic factors with drugs used to induce labour. He is also interested
in whether infections may provoke an auto-immune response. One
respondent to the survey, who works with autistic children in Sweden,
agreed.
She said: "I think the reason that the number of
patients with autism has increased since 1980 is that we use the
diagnosis of autism in a much broader way today than we did 20 to 30
years ago.
"Many of these children had other diagnoses 20 years
ago, such as mental retardation or a psychiatric diagnosis."
The symptoms of autism vary enormously from child to
child. Some may appear indifferent or aloof, others never make
spontaneous approaches to others.
Empathy is difficult and children can find it hard to
develop play and imagination.
They also have difficulties with communication. They
may not understand gestures, expressions or tone of voice, and they may
find it difficult to understand the uses of communication. Language is
often used literally, occasionally with limited use of words.
Since the classic symptoms of autism were first
described by Leo Kanner in 1943, the definition has become broader and
estimates for incidence have risen.
The cause of autism is still unknown and there is no
cure. The condition does appear to run in families.
Autism is usually detected only when a child begins to
develop speech - often in the second year. This is the same time that
the MMR vaccine is normally given.
Critics of the MMR hypothesis say thousands of children
between 12 and 18 months will be diagnosed with autism every year. By
the law of averages, several hundred will develop symptoms soon after
getting an MMR jab, even though
the events are unlikely to be connected.
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