More girls are being diagnosed with autism – 26/06/2023 – Health

Morénike Giwa Onaiwu was shocked when daycare workers observed some worrying behavior from her daughter, Legacy. The little girl did not react when she was called by her name. She avoided eye contact, spoke little and liked to play alone.

But none of this seemed out of the ordinary for Onaiwu, a Houston-based consultant and writer.

“I didn’t recognize there was anything wrong,” she explained. “My daughter was just like me.”

Legacy was diagnosed with autism in 2011, just before her 3-year-old birthday. Months later, aged 31, Onaiwu received the same diagnosis.

A neurodevelopmental disorder characterized by social and communication difficulties, in addition to repetitive behaviors, autism has been associated with boys for years. But in the past decade, with more doctors, teachers and parents looking out for early signs of the condition, the proportion of girls who receive this diagnosis has been rising.

In 2012, the Centers for Disease Control and Prevention (CDC) estimated that boys were 4.7 times more likely than girls to be diagnosed as autistic. By 2018, the ratio had dropped to 4.2 to one. And in data released by the CDC last month, the rate was 3.1 boys to a girl. In this new analysis, based on the health and education records of more than 226,000 eight-year-olds across the country, the rate of autism among girls rose from 1%, the highest on record.

More adult women, like Onaiwu, are also being diagnosed, a fact that raises questions about how many girls have been misdiagnosed or haven’t been diagnosed with autism.

“I think we’re becoming more aware that autism can occur in girls and what the differences are,” commented Catherine Lord, a psychologist and autism researcher at the University of California, Los Angeles.

In the first autism study, published in 1943, Johns Hopkins University psychiatrist Leo Kanner identified 11 children – eight boys and three girls – with “a powerful desire for solitude and sameness.”

It was only in 1980 that autism was officially recognized in the Diagnostic and Statistical Manual of Mental Disorders (DSM), the main classification system used by psychiatrists. But the diagnosis was narrowly defined and involved a general lack of interest in other people, as well as language impairments and particular fixations, all elements that needed to be detected before the child reached 30 months of age.

Over time, when experts began to see autism as a broad spectrum of behaviors, the DSM criteria were expanded. Children with autism might have difficulty making friends or emulating others; they might have delays in verbal or non-verbal communication, or they might have limited or repetitive interests, such as a preoccupation with specific topics.

Most girls diagnosed with autism at that time had intellectual disabilities, which made them easy to spot, Lord said.

And, she said, many clinicians ignored that autism can manifest itself differently in girls who have less noticeable physical manifestations of the condition. Studies since then have shown that girls with autism are more likely than boys to camouflage their social difficulties, sometimes mimicking the behaviors of girls around them. What’s more, girls are often treated differently by adults – for example, they are encouraged to smile or participate more in group play. Even the toys used by clinical professionals to assess the possibility of autism in children were later criticized for being more attractive to boys.

“There have always been autistic girls,” Lord said. “I don’t think people would go out of their way to know that girls might be treated a little differently.”

The most recent edition of the DSM, published in 2013, recognized an even broader spectrum of behaviors that may be indicative of autism and specified that autism in girls may go unnoticed due to “more subtle manifestations of social and communication difficulties”.

Kevin Pelphrey, a neuroscientist and autism researcher at the University of Virginia Brain Institute, said that more than 15 years ago, when his own daughter started showing signs of autism, he didn’t even recognize the signs. Pediatricians told her, “It can’t be autism – she’s a girl.”

Brain systems involved in social behavior develop more quickly in girls, he said, and this could be a “protective factor” for girls with autism, especially in early childhood.

But as girls get older and social relationships between girls become more complex, girls with autism start to stand out more and are often bullied, Pelphrey said.

“This leads to another big difference between boys and girls: Girls’ likelihood of developing anxiety and depression can be much higher,” he said.

These psychiatric problems can hide the underlying autism and lead to misdiagnosis.

Dena Gassner, 61, a graduate student in social work at Adelphi University in Garden City, New York, had social and emotional difficulties since childhood, but doctors never mentioned autism as a possible diagnosis. Like many autistic girls, Gassner had been sexually abused, and her emotional problems were later attributed to it. And she was misdiagnosed as having bipolar disorder.

Gassner wasn’t diagnosed as autistic until she was 40, six years after her son received the same diagnosis. She said that at first she was baffled by the diagnosis, in part because her son’s difficulties — including language delays and fixations with certain movies and activities — were so different from hers.

“I would never have looked at my son and seen myself in his reflection,” she said.

Gassner and Onaiwu are members of the Interagency Coordinating Committee on Autism, a group of federal scientists and academics, parents, and adults with autism that advises the Department of Health and Human Services on research and public policy.

Now that they have met many other women diagnosed as autistic in adulthood, the two women said they suspect that the true difference between the number of autistic men and women is smaller than the data indicate.

“They’re not even looking at how many autistic girls there are — they’re looking at how many autistic girls we’re finding,” Gassner said.

In a 2017 review of dozens of studies, British researchers estimated that the actual sex ratio is closer to 3 to 1. Some online polls that include self-diagnosed people show an even smaller difference.

While there is no doubt that autism is underdiagnosed in girls, most experts say it is more prevalent in boys. Autism has strong genetic roots, and some studies suggest that sex differences may stem at least in part from innate biological differences. For example, girls with autism tend to have larger genetic mutations than boys. Girls may need a larger genetic mutation to be impacted, Pelphrey suggested, possibly because they carry protective genetic factors.

The demographic changes of autism are not limited to gender. The proportion of children of color with autism has increased rapidly over the last ten years. In the new CDC report, autism rates among black and Latino 8-year-olds surpassed those of white children for the first time.

“In the past, autism was seen as something that affected little white boys, and sometimes those little white kids, growing up, would become ‘Star Trek’ fans or programmers in Silicon Valley,” Onaiwu said. “It was thought that it didn’t happen to the rest of us – but it did.”

Translated by Clara Allain