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Researchers
studying home videotapes of children's first and
second birthday parties have confirmed what a
number of parents have been claiming for years
-- that some youngsters who are seemingly normal
at age 1 regress and exhibit the characteristic
behaviors of autism by the end of their second
year.
In a study published today in the Archives of
General Psychiatry, research done at the University
of Washington's Autism Center provides the first
objective evidence for autistic regression. This
form of autism is estimated to account for about
25 percent of all autism cases in the United States.
The study did not address the cause of autistic
regression or the possible role that childhood
vaccines might play in children developing autism,
according to lead author Geraldine Dawson, director
of the UW's Autism Center.
"Once again, this study provides an important
lesson that parents are good reporters on what
is happening with their children. It underscores
the importance of professionals to listen to parents,"
said Dawson. "And it certainly suggests that
in early screening for autism that we need to
screen at 18, 24 and 36 months to find children
who develop normally at first, but then experience
a regression."
The researchers examined the birthday videos of
56 children -- 15 who were later diagnosed with
autism and whose parents reported that their children
experienced regression in the first three years
of life; 21 whose parents reported that their
child had symptoms early in life and had no regression;
and 20 typically developing youngsters. The children's
behavior was coded by trained observers who were
not aware of which children had been diagnosed
with autism or regression. Parents also filled
out a detailed questionnaire about their child's
development during the first two years of life.
Perhaps the study's most striking finding involved
verbal communication. The three groups differed
significantly in their use of complex babbling
and use of words at 12 months of age. Children
later diagnosed with regressive autism used complex
babbling and words much more frequently than those
diagnosed with early onset autism. Typically developing
youngsters fell between the groups of children
with autism.
However, a year later typically developing infants
showed a dramatic increase in the use of words
and complex babbling while the two groups of toddlers
with autism either lost their language or failed
to make meaningful gains.
Children with regressive autism at age 2 displayed
other symptoms of autism that didn't show up at
1, such as not pointing or using their body to
refer to objects, not turning when their name
was called and not looking at other people. Both
groups of children with autism significantly decreased
their amount of looking at other people in the
second year of life.
Dawson said these findings corroborate parent
reports that some children with autism use words
spontaneously and meaningfully, use gestures and
participate in social games early on and then
lose these skills.
The parental questionnaires also indicated that
children with regressive autism had regulatory
difficulties such as sleeping problems and being
soothed when upset prior to the onset of autism
symptoms.
"This does suggest that there might be an
early vulnerability in the development of the
nervous system and that these children weren't
developing normally," she said.
The researchers also found there were no differences
at ages 3 and 4 in the severity of autism, IQ,
adaptive behavior or neuropsychological functioning
between children with a history of regression
versus those with early onset autism.
The UW Autism Center continues to track the children
with autism in the study to see if there are differences
in the course of regressive autism from early
onset autism and to determine if regression is
a distinct form of the developmental disorder.
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