Parents are reporting cases of autism at double the rate of the last U.S. government survey in 2003, prompting calls for more research and spawning doubts about the true number of children affected.
Researchers estimate that now 1.1 percent, or 1 in 91 children, were told they had a disorder on the autism spectrum, according to a parent survey on the health of more than 78,000 children included in the National Survey of Children's Health. The last survey, conducted in 2003, estimated just 0.57 percent of children had autism.
But whether a change in diagnosis criteria or some factor in the children's environment, or a combination of the two, led to the jump in reported cases remains unclear.
"This [survey] means that there are a whole lot of families struggling with this and not enough resources," said Rita Sheffler, a mother of a child with autism and a member of the National Autism Association. "We need more funding and research and need it right away. If children don't receive appropriate treatments [at a young age], there aren't enough facilities for adults and society is not prepared if they do not find meaningful treatments."
Although many doctors are fighting for research dollars to investigate autism, specialists do not necessarily trust the numbers as an official estimate, especially because the survey wasn't set up to confirm or explore each time a parent reported an autism diagnosis.
"This should not be the 'official' estimate," said Dr. Max Wiznitzer, a pediatric neurologist at University Hospitals in Cleveland.
"While the authors state that the survey results [and previous surveys] are similar to results of reviews of records, both have a limitation -- the assumption that the parent report and the records accurately reflect the diagnosis," he said
Some of the reporting seemed to match to well-documented statistics, such as the fact that boys were four times more likely to be diagnosed with autism than girls in the survey, a commonly known gender difference in the autism community.
However, the high rate of recovery from autism reported by the parents raised the suspicions of doctors.
Children whose parents reported they had "recovered" from autism weren't included in the 1.1 percent estimate. A total of 38 percent of parents who reported being told by a health care provider that their child had autism also reported that their child had recovered.
"We either have to change our assumption and consider that autism might be a temporary state in some cases, especially mild cases, or else challenge whether these are true cases of autism," said Dr. L. Eugene Arnold, a professor emeritus of Psychiatry at Ohio State University. "I favor the former course."
He added, "I personally have seen youngsters who clearly had autism spectrum disorders at age 4 to 5 who seemed to outgrow it, possibly because of modern treatment."
However, other doctors have seen many misdiagnoses, leading them to believe some of the "recovered" children might have not have ever really had autism.
"Clinically, I have seen children who had been given the autism spectrum disorder diagnosis by other practitioners and did not have the diagnosis; even the parents questioned the autism spectrum disorder diagnosis after doing their own reading," said pediatric neurologist Wiznitzer.
Because of these differences, Wiznitzer thought the study -- published today in the journal Pediatrics -- was a litmus test for general socialization or communication problems among children.
"Whether they truly are the components of autistic spectrum disorder has not been proven in this survey," he said.
However, parents' reaction to the news was only affirmation of their fears and their calls for more research.
"The study shows that the increase in autism is real -- you can't have a genetic epidemic -- there are environmental factors in play," said Rebecca Estepp, national media manager for Talk About Curing Autism (TACA). "This is a national health crisis. ... If you're pregnant right now with a little boy [boys are more likely to be diagnosed], that's terrifying to find out. I don't know how it hasn't been declared a national health emergency."
Whatever the factors behind the jump in the rate of cases, the United States government is taking unprecedented steps to study autism further. This February, the American Recovery and Reinvestment Act (ARRA) funneled more money into scientific research thus giving the National Institute of Mental Health roughly $85 million toward new autism research projects.
"This is not business as usual for us. We were doing this before this paper came out, and we were doing this in recognition that autism was much more in common than any of us had thought," said Dr. Thomas Insel, director of the National Institute of Mental Health (NIMH).
Since the stimulus money only funded two years worth of research, Insel said the NIMH decided to direct extra money toward research with fast turnaround time -- including genomics.
"We're trying to develop new treatments and finding ways in which the environment might affect the genome," Insel said.
Dr. Ari Brown, a pediatrician and author of "Baby 411," also thought genomics held some of the most promise for autism research at the moment.
"We know there are certain genetic defects and chromosomal defects with huge incidence of autism spectrum disorders. We need to be looking at prenatal risk factors and exposures," she said. "I believe the 'hit' to a child's neurodevelopment happens before conception, at conception or shortly afterwards -- that's where the money is."
Courtney Hutchinson contributed to this report