Increase in autism diagnosis rates since 2000

The CDC has found a steady increase in autism diagnosis rates since 2000. Reasons for this are unknown, but may be due to increased awareness.

Autism rates in children have continued their steady rise, surging 30 percent in two years, according to the latest data released Thursday by the Centers for Disease Control and Prevention. While 1 in 88 children were estimated to have autism in 2008, public health officials now estimate that 1 in 68 children are on the autism spectrum.

Those statistics are based on the 2010 medical records of 8-year-olds living in 11 communities throughout the United States that are part of the CDC’s autism surveillance network. When the CDC started its surveillance of these communities back in 2000, the incidence of autism was 1 in 150 children.

CDC officials couldn’t offer specific reasons for the rise beyond increased awareness of the condition among doctors, teachers, and parents. “It may be that we’re getting better at identifying autism,” said Coleen Boyle, director of the CDC’s National Center on Birth Defects and Developmental Disabilities, during a press briefing. “We do feel like some of this has to do with how children are identified, diagnosed, and served in their communities.”

Autism advocacy groups noted that the increasing prevalence underscores the need for research funding to identify the causes of autism. “To be perfectly frank, it’s an incomplete picture right now,” said Robert Ring, chief science officer at Autism Speaks, a research advocacy organization in New York City. “All the pieces of the puzzle aren’t in place.”

Certain trends have remained constant during the decade that the CDC has been collecting data. Autism remains five times more common in boys — affecting 1 in 42 compared with 1 in 189 girls — and white children are more likely to be diagnosed than black or Hispanic children, though the prevalence in those minority groups has risen at a faster rate than for whites.

About half of children with autism in 2010 had average or above-average intelligence, compared with a third in 2002.

“We now recognize that autism is a spectrum,” said Marshalyn Yeargin-Allsopp, chief of the CDC’s developmental disabilities branch. “Our understanding has evolved to the point that we understand that there are children with higher IQs who may not have been receiving services in the past.”

The CDC provided grants to 11 states across the country — including Arizona, Arkansas, Maryland, and Wisconsin — based on their ability to survey medical and school records for pediatric autism diagnoses. Massachusetts is not one of the sites providing data to the federal government.

Autism rates varied widely among the 11 areas under CDC surveillance. In Alabama, only 1 in 175 children had autism in 2010 compared with 1 in 45 children in New Jersey.

That difference could reflect varying access to expensive autism assessments and therapies among states. New Jersey mandated in 2010 that insurance companies must cover $36,000 per year in behavioral programs and other autism therapies for any person under age 21 who is diagnosed with the disorder. Alabama didn’t pass a coverage mandate until 2012. A Massachusetts coverage law took effect in 2011, and more than 30 other states instituted such laws as well.

Some children with behavioral or intellectual disabilities other than autism may receive the diagnosis from their doctors in order to qualify them for coverage for treatments that could benefit them too, said Dr. Sarah Spence, codirector of Boston Children Hospital’s Autism Spectrum Center. “Kids may get labeled with autism disorder because that’s the best way for them to get services, but I don’t think this overdiagnosis is a huge piece of the rising incidence.”

More likely, doctors have become more attuned to early signs of autism in toddlers and preschoolers, such as failure to make eye contact, smile, or express emotional attachments to their caregivers. The American Academy of Pediatrics recommends that health care providers conduct autism screening tests at every well-child visit.

“Doctors are getting better at doing these screenings,” Spence said, “to the point where every once in a while, I can happily tell parents that their child’s language delay isn’t autism.”

Despite this increased awareness, the average age at which a child is diagnosed hasn’t budged much; most children aren’t diagnosed until after 4 years of age, according to the CDC, two years after signs of the disorder usually start to appear.

“Research suggests that the earlier we intervene with treatment, the greater the probability that children will realize their full potential,” Ring said.

In an effort to get children diagnosed earlier, the US Department of Health and Human Services revealed an educational campaign on Thursday to make parents, teachers, and health care providers even more aware of early autism signs. Parents are advised to look for certain expected milestones in their child’s development, such as developing a fear of strangers, responding to other people’s emotions, and looking in the mirror by age 6 to 9 months.

One problem, however, that still remains unaddressed is the lack of behavioral specialists to assess and treat the growing population of children displaying signs of autism.

“The wait lists in Boston for assessment and treatment are too long,” Spence said, “and that’s unacceptable because every month counts when it comes to starting therapy.”

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