Nearly 1 percent of children nationwide have autism - with the disorder more than four times more common in boys than girls, according to new figures released by the U.S. Centers for Disease Control and Prevention.
The report, which is in keeping with recent studies that tried to put a number on the puzzling neurobiological disorder, finds an average of one out of every 110 8-year-olds showed symptoms of autism, a sharp increase from the widely cited 1 in 150 figure from the CDC's study on autism's prevalence issued two years ago. Another recent report, based on parent surveys, found autism in 1 in every 100 children.
Researchers and therapists have long known that autism affects boys more than girls. The new study underscores that disparity: 1 in 70 boys was diagnosed with it compared with 1 in 315 girls, according to the CDC data, considered the most comprehensive estimate to date on autism.
In Maryland, the figures mirror the national average, with as many as one out of every 109 8-year-olds diagnosed with autism - a wide range of disabilities known as autism spectrum disorders, marked by impaired communication and social interaction.
Catherine Rice, a behavioral scientist with the CDC and the report's author, said the figures reveal a "significant public health issue" and underscore the need for unraveling the causes of autism and coordinating a response to better serve people struggling with the disorder.
"This is a major issue," said Dr. Gary Goldstein, president and chief executive of the Kennedy Krieger Institute in Baltimore, which specializes in children with developmental disabilities. "We need a system for this. We need to have recognition and early intervention and we need research to understand what's causing all this stuff."
The figures come from 2004 and 2006 data collected from 300,000 children in 10 states, including Maryland, where researchers analyzed school records in six counties. They also gathered diagnoses from such local institutions as Kennedy Krieger, the University of Maryland Medical Center and Mount Washington Pediatric Hospital.
More may be at risk
Researchers aren't sure why the numbers appear to be increasing but say they can't rule out that more children are at risk for developing autism.
For years, the disorder has baffled scientists, who have been trying to unlock the mysteries of autism and determine whether there is a true increase in its prevalence. While some specialists think genetics are its main cause, others see environmental factors or a combination of the two. And many experts attribute some of the growth to increased awareness and better diagnosis.
Still, while more children may be getting diagnosed, the CDC data suggest it isn't happening early enough.
Many children are not diagnosed until they reach kindergarten - and by then, it's too late for critical early interventions, Goldstein said.
CDC data from 2006 show that children are being diagnosed on average just a month earlier than in 2002. The average parent showed concern that his or her child might have autism at age 2, but a diagnosis didn't come for as long as three years later.
"That's not good enough," Goldstein said. "We don't have enough people doing [diagnosis], I don't think we're out there recognizing children and doing it for all the kids that need it. And we don't have the trained professionals."
Goldstein says he has seen the increase in autism over the past decade as more parents walk through Kennedy Krieger's doors seeking help for their children.
Fifteen years ago, a Kennedy Krieger treatment program for 2- to 4-year-olds with autism had just four children, and specialists wondered whether it was worth keeping. Today, the program has 75 slots and is always full, with a waiting list.
The new figures present a challenge for school districts that will undoubtedly see increasing numbers of children with autism in their classrooms, said Goldstein. "How are they going to cope with this problem and provide early intervention?" he said.
Maryland's special-education administrators have been trying to prepare for what they expect will be about a 6 percent increase in the number of children with autism next school year, said Karla Saval, who coordinates the Maryland State Department of Education's initiatives for youth with autism with other agencies.
Last year, 7,510 children with autism were educated in Maryland public schools. That figure was just 260 in 1993, when the agency began keeping track, she said.
The department trains its teachers to better serve autistic children, including a program where preschool teachers get training from specialists at Kennedy Krieger, Saval said.
'Public health crisis'
"We are definitely feeling the impact across local school systems," she said. "We have to assist local school systems in meeting the academic, social and vocational needs of children with autism. Autism just presents such a wide array of challenges in all those areas."
The CDC data indicate "a major public health crisis" and a need for more money to fund autism research and programs for children and adults with the disorder, said Geraldine Dawson, chief science adviser for the advocacy group Autism Speaks.
"That means that 750,000 children are now estimated to have an autism spectrum disorder, and those children will be growing up to be adults and will need services throughout their life spans," she said.
She pointed out a 2007 study from the Harvard School of Public Health that found the nation spends $35 billion each year to care for people with autism. And yet, in 2008, just $177 million was spent on research.
"Without answers to understand why we are seeing this increase, we are not going to be able to develop ways of preventing or more effectively treating autism," Dawson said.
In addition, researchers need more families to participate in studies to nail down autism's causes, said Goldstein. About 10 percent of all affected families participate in research, he said. As far as genetic research goes, just a fraction of the genes that might be responsible for autism have been identified, Dawson said. And scientists are still mystified by what environmental causes might play a role.
"We still need to identify more of the genes, and more of the exposures," he said. "Successes in childhood cancer came when nearly every child with cancer was involved in a clinical trial. That is not the case with autism. We really need to encourage families to get that participation rate way up."
Complicating matters are the likely various subtypes of autism with different causes, said Li-Ching Lee, a psychiatric epidemiologist at Johns Hopkins Bloomberg School of Public Health, who gathered the Maryland data for the CDC report.
The figures are essential for policymakers as they consider research funding and expanded programs for children and adults with the disorder, said Lee, who is also investigating prevalence of autism in China and Taiwan. "This can give us a guide as we develop future studies."