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NJ: "Autism rate rose 300% in...New Jersey between 2000 and 2016"; "true increase"

Feb 17, 2023, N.J. autism cases have jumped 300% in 16 years. Rutgers researchers aren’t sure why

Autism remains an evolving diagnosis.

The developmental disability wasn’t classified a standalone disorder until 1980. Then in the mid-1990s, it was labeled a spectrum disorder.

But even now, experts continue to debate the criteria of just what autism is — and the root causes behind the precipitous rise in cases.

The autism rate rose 300% in parts of New Jersey between 2000 and 2016, according to a new Rutgers University study published in the journal Pediatrics. The research also found a 500% rise in children with autism spectrum disorder and no intellectual impairment.

Researchers collected data from more than 4,600 8-year-olds identified with ASD from four New Jersey counties — Essex, Hudson, Ocean and Union — in that period.

“A 500% increase cannot just be … attributed to better awareness fully,” said Josephine Shenouda, an adjunct professor at the Rutgers School of Public Health and lead author of the study. “It doesn’t really make sense. So there is a true increase.

“And there are environmental factors that we can point to. We can say that parental age is a factor that increases autism, and we have seen in our metro area here that the average age of first pregnancy has been on the rise. That’s a contributing factor that we know of.”

For decades, autism has been tied to one’s intellectual capacity. But a fivefold increase in cases was found among kids who have no intellectual disability, meaning they met the criteria for an ASD diagnosis but had an average or above-average IQ.

It was previously thought that 50% to 70% of children with autism were intellectually impaired, experts say.

“What this study really shows is that over time, we’re seeing that over 70% — or two out of three — children that we’re identifying today are without intellectual disability,” Shenouda said.

Researchers also found a twofold rise in 8-year-olds with ASD who were intellectually impaired.

So what does that tell us? What does the rise in children with ASD and no intellectual impairment say about the evolving nature of the disorder? What does it mean to have an autism diagnosis today? And are there more cases of ASD, or are we just getting better at diagnosing the disorder?

The answers are not clear-cut.

Some experts believe there is a true rise — that more children are being born with ASD, though the extent remains an ongoing debate. The current rate of ASD in the U.S. is 1 in 44 kids, according to the Centers for Disease Control and Prevention. In New Jersey, it’s 1 in 35.

The data alone can be startling without context. In 2000, the U.S. rate was 1 in 150, according to the CDC. Six years later, it was 1 in 110. And six years after that? 1 in 69.

“Has (diagnostic criteria) changed over time? Yes, a little bit. Is it better recognition? Yes, that plays a role in it. Is there a true increase in autism? I think so,” Shenouda said. “I think there (are) a lot of environmental factors that should be studied. And we should try to figure out if this is a true increase over time.”

While experts are “much, much better now at identifying it,” she says, better diagnostic tools alone do not explain a 300% spike.

Shenouda believes something else is occurring, citing environmental factors like parents — especially fathers — having children at older ages.

But other experts, while acknowledging the possibility that environment factors are playing a role, think the rate has remained largely stable.

“Most epidemiologists believe that the rate has been about the same and always has been the same, even hundreds and hundreds of years ago. We’re just identifying it now in a different and better way,” said Stephen M. Kanne, director of the NewYork-Presbyterian Center for Autism and the Developing Brain.

Reading headlines, you might think the U.S. is experiencing an epidemic of sorts. “Everyone is shocked, and they’re like, ‘Oh my God, is this something in the water? What’s happening? Why is autism on such an increase?’” Kanne said. “If you drill down in the data, the lion’s share of the increase in prevalence that we see — 90% of the people out there agree it has to do with how we changed the diagnostic criteria.”

Kanne, who is also a professor of psychology at Weill Cornell Medical College, said much has changed in the past two decades….

“As we learn more and more over the years about what autism really is and how to identify and how to diagnose it, that bucket’s gotten bigger and bigger. So we’re identifying more people with the disorder appropriately, and that creates the rise in prevalence that really does account for the lion’s share of what you’re seeing.”

Experts once used three categories to determine an ASD diagnosis: social skills, communication, and repetitive and/or restricted behaviors, Shenouda said. But the updated criteria now has only two domains: social communication and behavioral issues….

He emphasized the rising rates, in his view, were mostly from better diagnosing, though noted the environment could be a factor.

But definitive answers remain elusive.

Researchers have studied genes, premature birth, air pollution, pesticides and certain medications, like SSRIs (selective serotonin reuptake inhibitors), as possible factors. Still, the exact cause or causes of the disorder remains unclear.

Kanne hesitates to use the phrase “environmental factors,” as “people read into that many different things.” Many people think vaccines are to blame, though experts and the CDC repeatedly have maintained “there is no link between autism and any vaccine or vaccine ingredient.”…

“Future work should focus on addressing health disparities in the identification of ASD through the expansion of screening programs and improved linkage to care.”


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