Diagnostic disparity of Autism diagnoses between sexes.

Author: Shelby Cox

Title: Diagnostic disparity of Autism diagnoses between sexes.  
 
In this discussion, we focused on the variation in manifestation and diagnostic disparity of autism spectrum disorder (ASD) between sexes. In a review titled “Sex Differences in Autism Spectrum Disorder: Diagnostic, Neurobiological, and Behavioral Features” the authors analyzed the discrepancies in sex ratio of ASD diagnosis and its manifestations of core symptoms along with the discussion of current and past theories that have been used to explain this gap. 

The prevalence of autism spectrum disorder is about 1 in 44 children and is diagnosed in boys 4.2 times more than in girls. This discrepancy is interesting considering that there is not a very pronounced sex difference in Autism screening. This means despite receiving the same testing, boys are more likely to receive an ASD diagnosis. The standardization of diagnostic tools and criteria has been primarily based on presentation in males, which likely contributes to a lower rate of diagnosis in girls compared to boys. Additionally, it has been found that women diagnosed with ASD later in life often had a history of multiple other previous diagnoses before ASD, whereas men usually did not.  
After explaining the differences in diagnostic rates, the authors then describe common variation in core symptoms that make it more difficult for women to be diagnosed with ASD. Camouflaging, or minimizing the visibility of traits associated with ASD, is reported much more often in women with ASD, which could result in the disorder going unnoticed. Along with this, women with ASD commonly display more internalizing behaviors such as depression, anxiety, and other emotional issues than men with ASD who commonly display more externalizing behaviors such as aggressiveness and hyperactivity. Externalizing behaviors are more likely to be disruptive to others, especially at a young age in schools, making it more likely for young boys to be tested forASD.  

Following this, the article gives theories that have been used to rationalize the sex ratio discrepancy. The Extreme Male Brain Theory links ASD susceptibility to morphological differences such as the total size or volume, white and gray matter ratio, or hemispheric connectivity between male and female brains. This theory states that the male brain is more fit for systemizing, while the female brain is more fit for empathizing, and that ASD is an extreme of the normal male profile. Systemizing is defined as “the ability of analyzing a system and understanding the rules that govern it,” while empathizing is defined as “to identify mental states and to respond with appropriate emotions.” This indicates that a person with ASD would have a very good ability to systemize but is unable to empathize. A major issue with this theory is that it reinforces a negative stereotype that people with ASD lack remorse and ability to sympathize and empathize. In contrast, the Female Autism Phenotype Theory states that female specific manifestations of ASD do not fit the current conceptualizations of the disorder. This relates back to earlier mentioned differences in core symptoms as well as the idea that women with ASD have been found to show greater social motivation, capacity for friendship, and pragmatic social communication.  

Napolitano, A., Schiavi, S., La Rosa, P., Rossi-Espagnet, M. C., Petrillo, S., Bottino, F., Tagliente, E., Longo, D., Lupi, E., Casula, L., Valeri, G., Piemonte, F., Trezza, V., & Vicari, S. (2022). Sex Differences in Autism Spectrum Disorder: Diagnostic, Neurobiological, and Behavioral Features. Frontiers in psychiatry, 13, 889636. https://doi.org/10.3389/fpsyt.2022.889636