Date:
04/01/2008 02:41 PM High
rate of autism signs found in children born extremely prematurely,
researchers find
By LINDSEY TANNER
AP Medical Writer
CHICAGO (AP) _ A small study of toddlers finds
that about one-quarter of babies born very prematurely had
signs of autism on an early screening test.
The research is preliminary since formal autism
testing wasn't done. But the results are provocative, suggesting
that tiny preemies may face greater risks of developing autism
than previously thought.
That suggests autism may be an under-appreciated
consequence of medical advances enabling the tiniest of premature
babies to survive, said lead author Catherine Limperopoulos,
a researcher at McGill University in Montreal and Children's
Hospital in Boston.
She emphasized that the results don't mean
extreme prematurity causes autism, but rather that it might
be among contributing factors.
The risks associated with being born way too
early have mostly been thought of as "neuromuscular,
causing damage like cerebral palsy, and cognitive, like mental
retardation," said Dr. Alan Fleischman, medical director
at the March of Dimes.
"The study says there are also social
and behavioral consequences which look like autism,"
Fleischman said. And he said it underscores a need for early
autism screening among youngsters born very prematurely.
The American Academy of Pediatrics recommends
autism screening for all children by age 2. Autism can't be
cured but early behavior therapy can help lessen its severity.
Experts believe autism results from a combination
of genes and outside influences. Some advocates believe those
factors include childhood vaccines, but scientific studies
have not shown that.
Previous research on autism and prematurity
has generally looked back at groups of older children to see
whether prematurity was more common among those already diagnosed
with autism, and results have been inconsistent, said Craig
Newschaffer, an autism researcher at Drexel University's School
of Public Health.
Limperopoulos said her study design was more
rigorous.
The study, released Wednesday and published
in the April issue of the journal Pediatrics, involved 91
children aged 18 months to 2 years old. On average, they were
born 10 weeks early weighing less than 4 pounds. Screening
results found suspected autism in 23 children, or 25 percent.
The screening test is a 23-item checklist
for parents, asking about behavior in very young children.
The test is designed to screen youngsters before age 2, which
is the more typical age of autism diagnosis. More comprehensive
and definitive autism testing at around age 2 is recommended
for those with positive screening results.
Dr. Edwin Cook, an autism researcher at the
University of Illinois at Chicago, said using the preliminary
screening test in preemies may be misleading because these
children typically reach developmental milestones later than
their peers but often catch up.
The researchers took developmental delays
associated with prematurity into account, Limperopoulos said.
She said the children in the study will be followed to see
how many are subsequently diagnosed with autism.
Newschaffer said there's evidence that fewer
than half of children the screening test identifies as at
risk of autism are later diagnosed with it.
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On the Net:
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