Autism rates have been increasing steadily in the US for decades – but nowhere as steep as in New Jersey, according to a new report.
Although modest increases were seen in five other states detected by the Centers for Disease Control and Prevention (CDC) report, there has been an astounding 43 percent increase in autism among four-year-olds in just four years.
Awareness of autism has certainly increased and New Jersey has some of the most reliable data on the condition, but the report's authors say these factors are not nearly enough to explain such a sharp rise.
What explains New Jersey's high and growing rates of autism remains a mystery.
One in 35 children in New Jersey is in the autism spectrum and the percentages among four-year-olds have risen by 43 percent in four years, a new CDC report finds
Nationwide, between one in 40 and one in 59 children has autism, depending on which estimate you view.
In New Jersey it is one in 35.
Across the seven states in the new CDC study – Arizona, Colorado, Missouri, North Carolina, Utah and Wisconsin, in addition to New Jersey – autism rates have increased by about 27 percent between 2010 and 2014.
Taken together, the average percentage of autism is 1.7 percent for four-year-old children.
But in New Jersey it is three percent – an increase from one percent in 2000 and a score of 43 percent between 2010 and 2014.
The difference between an increase of 27 percent and an increase of 43 percent is considerable and is difficult to explain in this case.
Autism as we know it – a varied set of behavioral conditions on a spectrum – received its first recognition in 1994 in the Diagnostic and Statistical Handbook for Psychiatric Disorders (DSM) 4.
Because it described different subsets of characteristics that needed to be treated in a unique way, doctors began to learn more about the spectrum of disorders and to diagnose more children with autism.
& # 39; As with any new invention or discovery, early adopters turn it on immediately, bulk takes more time, so you expect rates to rise slightly as you become more aware, & # 39 ; says co-author Dr. Walter Zahorodny, a professor of pediatrics at Rutgers University.
& # 39; About 10 to 20 percent [of upward variation] could be explained by better consciousness, so you could see a change from, for example, 1.1 percent to 1.4 percent over a four-year period, and then it would stabilize.
& # 39; But there is no reason to vary it in use for so many years [of the DSM 4 and 5 criteria]and yet people use that "better consciousness" as if it would explain a 150 percent change [since 2000]& # 39;
Autism is thought to start with a genetic predisposition – so far scientists have linked about 65 genes to the spectrum of disorders – and then triggered & # 39; due to environmental factors.
From there, the possibilities become virtually endless.
The most important environmental links have been between autism and perinatal exposures, or things that happen while a baby is in the womb and right after birth, including contact with pollution, having older parents, being twins or more, premature birth, NICU stay and more.
Dr. Zahorodny and his research team compared data on the perinatal risk factors that the children were confronted with in their research, to data on autistic rates.
& # 39; Some of these factors associated with an increased risk of autism … are all independent or semi-independent risk factors for autism & # 39 ;, says Dr. Zahorodny.
& # 39; But they all don't seem to coincide with an increase in prevalence as we saw.
& # 39; All together [perinatal factors] may account for five to ten percent of the total, but they are not enough to bring the prevalence from one to three percent. & # 39;
For 8-year-olds, the speed on all sites has increased by 150 percent since 2000.
But the wave in four-year-olds, which often has no clear clinical symptoms, was a strange phenomenon and, quite unique for New Jersey from the seven states.
Missouri had the lowest prevalence of autism, and there were no significant changes in it or any of the other states besides New Jersey.
But there is no clear explanation for the anomaly in New Jersey.
& # 39; There is something that can vary and raise rates, something that would affect the widest sections of the population – all children, all backgrounds and regions seem to be effected – but I don't even know if I have any good hypotheses about what it was, & # 39; Dr. Zahorodny says.
For now, our best response to the finding is that everyone should be wary of autism, says Dr. Zahorodny.
& # 39; If you have any questions about the development of your child between the ages of 18 and 30, take it to the doctor or family doctor, & # 39; he suggests.
& # 39; And if you are an activating person, trying to get other people to do something positive, try to get it [your doctor] o Use an autism screener for all children, not just sporadically, but for all children. & # 39;