The underdiagnosis of autism in women

Autism Spectrum Disorder, a neurodivergent condition that impacts social interaction, affects an estimated 250,000-300,000 people in Nepal, with 60,000-90,000 people classified as severely affected. Autism Spectrum Disorder, or ASD, has been thought to predominantly affect males, with a male-female diagnosis ratio of 4:1. However, recent studies have proposed  that this ratio is closer to 3:1, with a considerable population of females being diagnosed late or undiagnosed.

To understand the cause behind poor diagnoses, it is essential to understand the early days of autism research. The term ‘autism’ was coined by the Swiss psychiatrist Eugen Bleuler in 1911 and was used to describe a set of schizophrenia symptoms that involved withdrawal from the external world and increased focus on oneself. 

Later, in the 1940s, researchers Leo Kanner and Hans Asperger used the term to describe a group of children who displayed similar social and communication difficulties but did not fit the profile of schizophrenia. These two  researchers played a crucial role in highlighting autism as a separate developmental disorder. However, these studies were performed with a sample size unrepresentative of autism as a whole. 

The first study (1943) had a sample of 11 children: three girls and eight boys. The  following study was entirely composed of boys. Male-centric research is not just a problem of the past. The current ascertainment bias towards males is 15:1, with males being 15 times more likely to be chosen in a study for autism than females. As most of the existing data focuses on autism in boys, the measures used to define and diagnose autism are also more applicable to male behavior, leaving many girls with late or no diagnosis that can affect them for the rest of their lives.  

To tackle this issue, a recent study analyzed autistic behavior in a sample of both boys and girls. After careful evaluation, they created a list of ASD symptoms that varied from gender to gender. However, there were limitations to the study. Although the focus of the study was to search for symptoms in girls without intellectual disabilities, the ratio of diagnosed boys to girls was an astounding 11:1. They discovered that:  

● Girls were better at adjusting their behavior to fit social contexts.  

● Girls exhibit fewer patterns of similarity concerning restricted, repetitive behavior. 

● Girls were more aware of social conventions and codes of conduct and more influenced by peer pressure. 

● Girls have stronger communication skills. 

● Girls develop significantly fewer routines in specific interests. 

● Girls were less distressed in noisy, crowded places. 

● Girls had fewer non-verbal communication issues compared to boys. 

While this is just the result of one study, it proposes that autism presents itself slightly differently in girls than boys, with girls having fewer social hindrances and lacking the stereotypical repetitive behavior that currently characterizes autistic behavior. These differences are unaccounted for in diagnostic manuals, further hindering a clinician's ability to make a sound diagnosis.  

Diagnosing autism isn’t as easy as putting a patient into an MRI machine. Clinicians must refer to the DSM-5, the diagnosis and statistical manual, to confirm if their patient checks  the boxes for autism. As mentioned earlier, the DSM and most other checklists are based on male-centered studies and are more applicable to men than women. For example, one of the possible requirements for autistic behavior is, as stated: “Stereotyped or repetitive motor  movements, use of objects, or speech (e.g., simple motor stereotypes, lining up toys or flipping objects, echolalia, idiosyncratic phrases).” Some of these behaviors, such as hand wringing, rocking, and restrictive repetitive movements, appear more in boys than girls.

Here’s another example. “Highly restricted, fixated interests that are abnormal in intensity or focus (e.g., strong attachment to or preoccupation with unusual objects, excessively circumscribed or perseverative interests).” The “restrictive, repetitive patterns of behavior and interest” described often present differently in girls, with girls engaging seemingly ordinary interests like animals, celebrities, or a specific TV show. These interests usually reach a near obsessive level, but they are not “stereotypical” autistic traits, so they often go overlooked. None of these differences are acknowledged by the DSM, as the criteria for ASD show no  variance in gender.  

One final factor in the underdiagnosis of girls is a behavior known as camouflaging. Camouflaging refers to masking social impairment or behaviors to fit society’s standards. Due to gender expectations, women feel more pressure than men to conform to societal norms; therefore, females are more likely to engage in camouflaging behavior. Camouflaging, or masking, can occur in girls as young as 7-8, making it harder for parents to notice and report irregularities in their child’s behavior if they have not already been diagnosed. 

Dr Amit Jha, a doctor at Kanti’s child and adolescent psychiatric unit, observed that family members sometimes normalize symptoms of autism in girls, accounting for a girl’s social withdrawal to being “shy.” Ignoring autism symptoms early on can lead to late diagnosis, which is detrimental to a child’s  health in numerous ways. As mentioned earlier, behaviors like camouflaging can arise and delay  a diagnosis for even longer.  

So what is the importance of an early diagnosis? Younger minds have a higher level of  brain plasticity, or the brain's ability to adapt and change. Therefore, the sooner autism is diagnosed and cared for, the more effective treatment will be. Sita Koirala (name changed) pushed her family to seek a diagnosis for her two-year-old sister after she started developing signs of autism. After much resistance from her family, they booked an appointment, only to be told she was fine. 

As time passed and her symptoms worsened, they booked another consultation and finally got an official autism diagnosis. Now, her sister is receiving treatment and slowly improving her communication and social skills. However, it’s hard not to wonder if further intervention could have occurred if she had been diagnosed correctly the first time around and how a delayed  diagnosis impacted her lifelong development. 

All this new research raises the question of why autism presents differently in females. Dr Supekar and Dr Menon from Stanford School of Medicine sought the answer with a brain  mapping study. His research found discrepancies between the male and female motor cortex, supplementary motor cortex, and a portion of the cerebellum, brain areas responsible for motor function. Dr Supekar hypothesized that these differences could account for the disparity in typical symptoms of autism, such as hand flapping and repetitive behaviors. Another doctor in  the study, Dr Menon, adds: “Girls and boys with autism differ in their clinical and neurobiological characteristics, and their brains are patterned in ways that contribute differently  to behavioral impairments.” 

At the end of the study, Dr Supekar concludes: “The discovery of gender differences in both behavioral and brain measures suggests that clinicians may want to  focus diagnosis and treatments for autistic girls differently than boys.” While this is just a single  study and cannot be used to draw definitive conclusions, it is a promising explanation as to why  autism presents itself differently in male and female brains. 

To put it simply, the existing measures of autism could have a higher validity for boys than girls, resulting in missed and late diagnoses. While part of the ratio between diagnosed  boys and girls with autism is due to biological differences, the global ratio is likely 3:1 rather than the current accepted ratio of 4:1.  The children missed during diagnosis fall into a group that doesn’t show stereotypical autistic traits and risk spending their whole life struggling with an undiagnosed condition.

It should also be noted that while the 4:1 ratio is a global statistic—and there is not  enough data collected in Nepal to create a country-wide metric—it is safe to assume that the ratio of diagnosed girls to boys is even higher due to Nepal’s already gender-biased culture. Mental health is still an emerging field in Nepal. Therefore, if this issue can be addressed sooner  rather than later, the gap can be closed through further research, awareness, and capacity building. To treat our girls and boys equally, their conditions need to be looked at differently. Every stakeholder, from government to clinicians to family members, can help ensure every girl gets the treatment she deserves.