This story is part of a partnership between MedPage Today and VICE News.
Children with gender dysphoria may have a higher prevalence of Asperger syndrome than the general population, according to a small study that's the first of its kind in the United States.
Gender dysphoria is diagnosed when a patient identifies as the opposite of their birth gender. They often go on to live life in the gender of their choice and are then said to be transgender. Asperger syndrome is a neurodevelopmental disorder that's on the autism spectrum, and those who have it have normal intelligence but often find social interactions difficult.
In a small retrospective study of 39 children whose parents or guardians took them to a gender dysphoria clinic in Boston, about 23 percent were found likely to have Asperger syndrome. In the United States, about 1.5 percent of the general population has an autism spectrum disorder (ASD).
Dr. Daniel Shumer, who is now at the University of Michigan Health System, conducted the research with colleagues while he was a fellow at Boston Children's Hospital and reported the findings in the journal LGBT Health. Shumer said that the study adds to a small but growing body of evidence linking gender dysphoria and Asperger syndrome.
"We got a sense that a heck of a lot of kids had what we thought was autism or autism spectrum disorder — much more than we would think just by chance," he remarked. "We had been collecting data on Asperger syndrome for many years, so we had the opportunity to go back and look at all that data to try the answer the question of whether what we were seeing in the clinic was borne out by the data we had been collecting."
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Dr. Joshua Safer, an endocrinologist at Boston University who wasn't involved in the study, said that he would characterize the work as "provocative but not definitive," noting that those who treat transgender patients are already aware of discussion about an association between gender dysphoria and Asperger syndrome.
The children and adolescents included in the study had a mean age of 15.8 years, and were evaluated at the multidisciplinary gender clinic between 2007 and 2011. Twenty-two of them were born male and 17 were born female.
To screen children at the clinic for Asperger syndrome, doctors asked parents to fill out out a form that described 50 varying behaviors indicative of Asperger syndrome by answering "observed" or "not observed." The results were converted to a score called the Asperger Syndrome Quotient, or ASQ. If the score was higher than 80, the child was included in the list of those "possibly," "likely," or "very likely" to have Asperger syndrome.
Shumer and colleagues found that nine out of the 39 patients potentially had Asperger syndrome, with a score above 80.
Among these nine children, five were born male and four were born female. There were no differences in prevalence of Asperger syndrome among natal males and natal females in the study (22.7 percent vs. 23.5 percent).
Four of the patients already had an ASD diagnosis before they were presented to the gender clinic: one had a long-standing diagnosis of autism, another had a long-standing diagnosis of Asperger syndrome, and two had been recently given a diagnosis of Asperger syndrome by a referring psychologist.
Of the five patients not previously diagnosed with an ASD, four had been diagnosed with other mental health disorders, the researchers said.
The new study builds upon a 2010 Dutch study that found a 7.8 percent prevalence of ASD among patients at a gender dysphoria clinic, but the Dutch researchers were using a diagnostic test rather than a screening tool, which makes the analysis hard to compare. Instead, Shumer said the two studies "complement" one another.
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Having a study like this completed in the US is "important because clearly we know there are cultural components to how gender expression is understood and appreciated, and it's not always exactly the same from North America to Europe to anywhere else in the world," said Dr. Aron Janssen, a child psychiatrist at NYU Langone Medical Center who was not involved in the study.
Janssen said Shumer's study doesn't provide a conclusive ASD prevalence among gender dysphoric youths, but called it a good start. He conducted a separate study that found an increased rate of gender dysphoria among children with ASD, but it's still under review and has not yet been published.
"It's really about assessing what gender means to a population that may think of gender in a different way than the way most of us do," Janssen said, explaining that thinking differently about gender shouldn't limit treatment options for patients with ASD. In a way, he added, people with ASD may express their gender more authentically because they are not as swayed by social stereotypes.
Given the growth of gender programs and general awareness of gender dysphoria in the US, Shumer said it helps to know that there's a link between it and Asperger syndrome. He said he hopes his work will help pursuade doctors to screen transgender patients for ASD and know that they may need to take more care to explain hormonal interventions to their patients on the autism spectrum.
Among his next steps is getting a better understanding of why the link exists.
"From a scientific perspective, it could help us understand gender development in general," Shumer said. "This could help unlock some mysteries to both gender development and autism."