Dylan Dyke, a 12-year-old boy with autism, spends time with his ducks, Nibbles, left, and Bill, outside his home in Michigan on Aug. 2, 2018. (Cory Morse/The Grand Rapids Press via AP)

New study suggests autism overdiagnosed: Canadian expert

Laurent Mottron: ‘Autistic people we test now are less and less different than typical people’

Autism has become so overdiagnosed that within five to 10 years there could be almost no difference between groups of people who have been diagnosed with the condition and those who haven’t, a Montreal researcher warns following the publication of a new study.

A new meta-analysis published Wednesday in JAMA Psychiatry that analyzed 11 previous major studies carried out since 1966 found that individuals diagnosed with autism have become progressively less different from the general population.

Laurent Mottron, a research psychiatrist at the mental health unit of the Riviere-des-Prairies Hospital and one of the study’s authors, said the gap could soon narrow to nothing.

“Autistic people we test now are less and less different than typical people — really less and less, to the point where if the trend continues, we won’t be able to find the least difference within five or 10 years,” he said in an interview.

Mottron says the problem is that the criteria have lowered to the point where a diagnosis could become nearly meaningless.

Mottron and four other researchers conducted a meta-analysis of previous studies that compared people who have been diagnosed with autism with those who haven’t. The analysis, which included data from 27,723 individuals, includes practically “the whole of planetary research on the autistic brain,” he said.

The analysis found that the differences between the groups have decreased over time in five of the seven main constructs that define autism, including emotion recognition, theory of mind, planning and brain size.

READ MORE: B.C. parents hope service dog helps stop autistic child’s self-harming

In contrast, the group found no such tendency when it comes to the prevalence of schizophrenia, which has remained stable for the past two decades.

Globally, the number of people diagnosed with autism has risen dramatically in recent years, going in the United States from less than 0.5 per cent of the population in 1966 to more than two per cent. In Quebec, the number is approaching two per cent.

The study’s authors say their findings may be due to several factors, including a true increase in the condition, greater public awareness, the fact that a diagnosis leads to greater support, a lowered threshold for diagnosis, the use of “checklist diagnoses” and a greater tendency to diagnose individuals with a normal IQ.

They note that understanding of autism has also evolved ”from a narrowly defined clinical picture to a spectrum of conditions of uncertain similarity.” They warn that this blurring of the line could potentially make it more difficult to study the disorder.

Mottron, for his part, says the research points to a rampant problem of overdiagnosis that he blames on schools, doctors and parents alike. He goes so far as to suggest that a diagnosis can work in a school or parent’s best interest by making them eligible for extra help and funding that they may otherwise not receive.

“Right now, a diagnosis of autism is what allows one to get services in schools,” he said. “When you have an autism diagnosis, you have much greater chances of getting all kinds of extra things compared to another condition, which is total nonsense, because the need for services is independent from a diagnosis.”

He said the criteria for a diagnosis have become “trivial,” including a child’s lack of friends or a dislike of haircuts or tags on clothing.

Mottron acknowledged that the situation is complicated because mild forms of autism do exist. However, he noted that having certain autistic traits isn’t the same as having autism and said it’s “fundamental” for medical professionals to move beyond a simple checklist of symptoms before issuing a diagnosis.

He said the potential for misdiagnosis is problematic in many ways, including the risk of children receiving the wrong treatment.

RELATED: Amazon removes books that promoted autism ‘cure’

“The people who are diagnosed as autistic when they aren’t often have problems, but they’re not the same ones,” he said.

He said the cost of specialized services for autism are high and too many diagnosed children can spread resources too thin, meaning those who need them most don’t get enough.

Jean-Benoit Legault, The Canadian Press

Like us on Facebook and follow us on Twitter

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

Kernachan’s cartoon flashback 2018

Wildfire smoke comes in handy for other purposes

Clean air can’t be taken for granted

Wildfires are a major concern to our daily lives when conditions don’t clear the smoke

Logjams and gravel bars the bane of Chemainus River’s existence

Spawning fish impacted by low channels, residents by flood concerns

Calling those trying to act with compassion as ‘Do gooders and non-profits’ draws ire

Drastic and fundamental changes in the way we live and treat each other the only solution

Historical Moment

Lumber Kings grabbed some lumber and headed onto the ice to hit the puck around

Record-breaking 165 new COVID-19 cases diagnosed in B.C. in 24-hour period

Fifty-seven people are in hospital battling the novel coronavirus

March to protect old growth, stop industrial logging coming to B.C. Legislature

Organizers say they want to give frontline communities a bigger say in nearby logging

B.C. releases details of $1.5B economic recovery plan, $660M in business tax incentives

Economic plan includes support for employers, as well as training for workers

‘Not criminally responsible’ hearing slated for man convicted of Abbotsford school stabbing

Gabriel Klein was found guilty in March of killing Letisha Reimer, 13, in 2016

B.C.’s 1st mental health and addictions minister won’t be seeking re-election

MLA Judy Darcy is the fifth cabinet minister not intending to run in the next election

Remote B.C. tourism lodge staffed for coastal clean up instead of wilderness tours

The Great Bear Rainforest is home to exotic wildlife — and international trash

Most Read