A new study finds that girls are diagnosed with autism spectrum disorder (ASD) later than boys, possibly because females exhibit less severe and different symptoms than males.
Researchers at the Kennedy Krieger Institute in Baltimore, MD., presented their findings at the Pediatric Academic Societies (PAS) annual meeting in San Diego.
The comparison of gender differences in age at diagnosis, and symptom severity between boys and girls, was determined by a data review of the Institute’s Interactive Autism Network, an online registry that includes almost 50,000 individuals and family members affected by ASD.
In the registry, age of first diagnosis was available for 9,932 children, and 5,103 had completed the Social Responsiveness Scale, which identifies the presence and severity of social impairment.
In the data review, researchers found girls were diagnosed with pervasive developmental disorder, an ASD impacting the development of many basic skills, at a mean age of 4 years compared to 3.8 years for boys.
This also was the case with girls diagnosed with Asperger’s syndrome; girls were diagnosed at a mean age of 7.6 years for the condition, which affects language and behavioral development, vs. 7.1 years for boys.
In addition, they found girls struggled more with social cognition, the ability to interpret social cues.
Meanwhile, boys had more severe mannerisms such as repetitive behaviors like hand flapping, as well as highly restricted interests. Older boys, ages 10-15, also had more difficulties with the ability to recognize social cues and use language in social situations.
“This and other studies suggest that girls with ASD, as well as perhaps older women with this disorder, differ from males in key symptoms and behaviors, particularly around social interactions,” said Paul Lipkin, M.D., F.A.A.P., study author and director of the Interactive Autism Network at Kennedy Krieger.
“We must determine if the less recognizable symptoms in girls are leading not only to delayed diagnosis, but also under-identification of the condition.”
Researchers also saw an increase in the proportion of girls who were diagnosed with ASD in 2010-2013 when compared to 2006-2009.
Although the exact reason for the higher incidence is unknown, Lipkin, a neurodevelopmental pediatrician, believes a growing public awareness and more effective screening methods may be a reason.
Lipkin said detection methods and treatment protocols should be modified to meet the needs of each gender.
Source: American Academy of Pediatrics