Prevalence of Diagnosis
Researchers have been tracking the rate of autism diagnosis since 2000. Its has been raising steadily since then. This triggered fears of an “epidemic” but most of the increase is triggered by growing awareness of autism and the changes to diagnostic criteria.
The diagnosis does not have a test that can be seen in a laboratory. There is no blood test, brain scan or any definitive test. It relies on observation, medical history, behavior, and checklists by the autistic or a family member.
In the United States, the diagnositic criteria is in the Diagnostic and Statistical Manual of Mental Disorders (DSM). The criteria are struggles with social communication and interaction, “restricted” interests or “repetitive behaviors.” These are considered “core” features of autism.
The Center for Disease Control and Prevention (CDC) approximates that 1 in 44 children are autistic as of March 2023.
The History of Autism Diagnosis in the US
History books say that autism was discovered in the 1940’s in children with high support needs. It was really discovered in the 1920’s and no one gave this Jewish woman psychologist credit for differentiating autism from schizophrenia .
In the 1940’s autism diagnosis was only give to children who had very high support needs.
In 1966, it was estimated that 1 in 2,500 children were autistic. This was according to Kanner’s criteria. They only focused on autistics with high support needs.
In 1991, the US Department of Education said that an autism diagnosis qualifies a child for special education services. This is because autism was added to the Americans with Disabilities Act. Before this, many autistic children were listed as having an intellectual disability, even those who did not. This does not provide those children with an adequate education.
In 1994, the American Psychiatric Associated released the DSM IV broadened the definition of autism even more. This is when autism was put in the DSM, including Asperger syndrome and pervasive developmental disorder – not otherwise specified for children with low support needs.
Autism wasn’t introduced to the DSM until 1980. In order to get a diagnosis, a child needed to meet 8 of the 16 criteria instead of meeting all 6 criteria. This change increased the rate to 1 in 1,400.
The CDC researches collect health and school records of 8 year old children who live in the United States. These researchers are part of the Autism and Developmental Disabilities Monitoring Network. The CDC set this up in 2000 to approximate how common autism is.
Every two years, clinicians scan records for autistic traits. They focus on 8 year olds because most children at this age are enrolled ins cool and have had complete physicals by 2 years old.
The estimate is up 30% since the 1 in 88 report in 2008. It has more than doubled the rate of 1 in 150 in 2000. This trend has been steady since the early 1990’s and its globally, not just in the US. This is according to Maureen Durkin. She runs the site in Wisconsin.
After looking at the records, the ADDMN decide whether each child meets the diagnostic criteria , even if the child is not diagnosed. They calculate the results in each state.
The recent prevalence results are based on data from 11 network sites in 11 different states. The CDC wants to confuse on 10 of these sites for future examination. At 6 of these sites, the clinicians plan on looking at the records of both 4 and 8 year olds.
According to Eric Fombonne, a professor of psychiatry at Oregon Health and Science University in Portland, relying on school and medical records is not as accurate as assessing a child in person.
This approach also misses children who do not have school or medical records. This includes children who are home schooled and live in isolated regions. One example of this is the Amish community.
In 2012, it was reported that 1 in 88 American children were autistic.
In 2013, the DSM V was released and all different diagnosis were just autism. Aspergers syndrome and other diagnosis were eliminated and put into a single diagnosis.
In 2014, it was reported as 1 in 68.
Why is Diagnosis More Prevalent Now?
The increase in diagnosis is not due to just one factor. There are several. The theories are awareness, changing in reporting practices and increased access.
Increased awareness of how autistics are has contributed to the increase in diagnosis. Until the 1980’s many autistic people were institutionalized, making them unseen. Autistics were invisible to society. According to scientific research, parents who are aware of the presentation of autism are more likely to see a diagnosis for their child than parents who know nothing about autism. Living close to a city with good access has an influence too.
Policy changes also influence the increased prevelence of autism. In 2006, the American Academy of Pediatrics recommended screening all children for autism during routine doctor visits at 18 months and 24 months. This allowed children who would have been overlooked have the ability to receive a diagnosis and receive services.
Many autistic people who were diagnosed as adults were misdiagnosed with other conditions. One example is intellectual disability and ADHD. It is possible to be diagnosed with both but missing one does a real disservice to the individual. Ever since this was recognized, the diagnosis of intellectual disability has decreased.
The DSM 5 allowed for people to have multiple neurodivergency diagnosis such as autism and ADHD.
Part of this was a group of students finding a flaw in a diagnosis tool and together with their professor rectified the problem.
This increase does not mean more people are autistic. Think about as a result of improved identification of people who had gone undiagnosed. This had led to greater awareness and understanding of autism. This resulted in increased efforts to diagnose people who have gone without a diagnosis or who would be going without a diagnosis.
The expansion of diagnostic criteria and better access to healthcare and screenings have contributed to this as well.
Researchers call this progress.
Barriers in Obtaining an Autism Diagnosis
New data shows as the rate of autism diagnoses increase, the sex and race gaps are decreasing. This prevalence is showing in other countries as well.
For the first time, Black, Hispanic and Asian or Pacific Islander children show a higher prevelance than white children. This shows the racial disparities that the autistic community has been talking about for years. It has not been eliminated yet but this is a good start.
A lot of people don’t think about it but race is a large barrier in getting an autism diagnosis. Autism has been historically highest in white children but it is changing. Black and Hispanic children have lower rates due to not having access to services in order to get a diagnosis. Having wide spread screening has improved diagnosis but there are still people who fall through the cracks.
The prevalence among BIPOC children was 30% higher in 2020 than in 2018. For the first time, the percentage of 8 year old children who are BIPOC are:
- Asian or Pacific Islander 3.3%
- Hispanic 3.2%
- Black 2.9%
Even though this is progress, Black autistic children with intellectual disabilities are identified at a much inherent rate than those from other racial groups. This means that some Black children who are not intellectually disabled are falling through the cracks.
When you see more kids of color with intellectual disability, it makes you wonder: Where are all those kids of color who don’t have intellectual disability? Are we just not picking them up?
Katharine Zuckermann, associate professor of pediatrics at Oregon Health & Science University in Portland
This shift is due to improved screenings, awareness and improvement to access of services. There is still much to be done but this is a great improvement.
This new data also shows that autism is more prevelent in boys than girls by a narrower margin. The current data is 3.8 times more likely but the old data showed 4.2 to 1 ratio in 2018.
Historically, when a female bodied person goes in to an evaluator for an autism diagnosis, they are often misdiagnosed.
According to a study at the University of Exeter, the increase of diagnosis between 1998 and 2018 was higher for AFAB than AMAB. This study was published in the Journal of Child Psychology and Psychiatry.
It was considered a boy’s disability but that theory is becoming a thing of the past. This study shows a marked increase in AFAB compared to AMAB.
As there is not a really plausible reason why autism should increase more in adult and females our study suggests the change is probably due to increased identification, and not more people with neurodevelopmental disorders per se
Lead Researcher Ginny Russel from the University of Exeter
The Lost Generation of Autistics
The lost generation or missing generation of autistics are autistics that receive their diagnosis well into adulthood. There are many reasons that these autistics were missed as children.
This is due to thousands of autistic children in the 1950’s and 1960’s were missed or were misdiagnosed and autism was not included in the DSM until 1980.
It’s very common how adults recognize they are autistic when their own child is diagnosed. I am included in this. There are numerous stories like this all over the internet but my diagnosis story is very unique as I have an ADHD diagnosis from the 1980’s.
Joseph Piven, a professor of psychiatry at the University of North Carolina at Chapel Hill says that stories about adult diagnoses are just the “tip the iceberg.” He also said that most people who are diagnosed as adults have struggled with the disability had no voice.
It’s because of this, autism looks different in adult hood and what it means to age when autistic is still unknown for the most part. We have some autistics speaking out but there is no way to know how many people were missed.
We don’t have that concept with autism that people live a whole life: What happened to them as they got older? This is just a huge area of no knowledge. There’s almost nothing written about autism and geriatric populations.
Piven
There are very few studies but there are some. These studies show that autistics diagnosed in adulthood also have comorbid conditions that have adequate support.
Piven uncovered a few other hints about autism and aging along with heart wrenching stories.
And reason older autistic adults are hard to find is because many of these autistics were hidden, according to David Mandela, an associate professor of psychiatry and pediatrics at the University of Pennsylvania. Many autistics who had high support needs were institutionalized until the 1980’s in places like Willowbrook.
Because of this, very few people had an idea of what autism looks like in adults, stimming is often mistaken for signs of obsessive compulsive disorder or psychosis. The majority of mental health professionals lack the skills or experience to differentiate autism from mental health conditions.
Piven had a hard time finding the “missing” autistic adults. In 2010, he assisted in organizing a working group in North Carolina to investigate aging and autism. Their first step was to look for adults aged 50 and older. They thought this would be easy at first but he has only found 20 adults. A lot of them were in their 80’s and 90’s.
All of the people that Piven found had temporal dementia that had been there before the autism diagnosis. This dementia has signs of social differences that look like autism. They were never really autistic. Looking at medical records alone wasn’t going to find the lost autistics.
After that failed attempt, the research team sent out more than 14,000 emails to an autism organization in North Carolina asking for people over age 50 to give them a call. They did not get any calls. There was a few email responses.
After this didn’t yield much results, they recruited from group homes and University of North Carolina’s autism program. They found 19 men older than 50.
You have to be able to interact, and communicate, and talk and rap all that in order to fit in.
Scott Hartman, a study participant
This is just a huge area of no knowledge. There’s almost nothing written about autism and geriatric populations.
Joseph Piven
In 2009, the Pennsylvania Bureau of Autism Services asked Mandela to look for the adults part of the missing generation in institutions. At first, Mandela was skeptical but he did agree to do it. He used a diagnostic process that would exclude some people from diagnosis.
We almost biased the presses to not find autism.
Mandell
Mandell investigated an institution called Norristown State Hospital. He went through storage rooms there and dug through storage rooms or records at Norristown. The records were of 141 residents of the facility and Mandell asked the staff to complete the Social Responsiveness Scale (SRS). This is a questionnaire often used in autism diagnosis.
For 61 of the residents, the research team found a living relative for the Autism Diagnostic Interview Revised (ADI-R).
Parents had exquisite and tortured memories of the child’s early experiences.
Mandell
After gathering all the data, the research team discovered that 14 of the residents were autistic and had fell through the cracks of diagnosis. This is 10% of the facility. 12 of these residents had been given a diagnosis of chronic undifferentiated schizophrenia. They were being treated for a mental illness they did not have. The antipsychotics were not working, it was evident in the medical records.
The frustration of the psychiatrists just leaped off the page. No matter how often they changed medications or tried different treatment strategies, these folks weren’t responding to the treatment. Of course, it’s because they didn’t actually have schizophrenia.
Mandell
As soon as they made this discovery, the research team informed the institution. They immediately started weaning people off the inappropriate medications as some of these medications have severe withdrawal symptoms.
Mandell and his research team have began similar studies in community mental health centers, first screening with the SRS and performing diagnostic interviews. The research team has screened about 800 people who are not intellectually disabled. Out of 60 who had in person assessment, four are autistic. There were more that were at the “cutoff for autism.” Those people were not able to meet in person at the health center to get a diagnosis.
Mandell said that restricting the screening to people who are not intellectually disabled could skew the results. He says that people who need the support will be the hardest to find.
According to a study published on August 27, 2022, people diagnosed well into adulthood are nearly three times more likely as autistics diagnosed in childhood to have mental illness.
Experiences of childhood – versus adulthood- diagnosed people are likely to be quite different. We don’t know if this is due to their being misdiagnosed with other conditions, or whether those diagnoses – for example, anxiety, depression – may be the effects of living without a proper autism diagnosis throughout childhood, adolescence and beyond. Probably both factors.
Lead researcher Vanessa Bal
This study took their sample from the SPARK data base of autistic participants diagnosed aged 21 or older. The study found that people diagnosed in adulthood were 2.7 times more likely to report co occurring mood, anxiety, personality or eating disorders than those diagnosed as children.
A major problem with the current tests is that they are not meant for adults, they are made for children.
These tests are not meant for a 65 year old. You pull out toys and have to say ‘ I know this is kind of silly, but just do it.’
Joesph Piven
This makes diagnosis for adults very difficult. This is a long process that will take a long time to complete, if it ever gets completed. As discussed above, autistic people who are diagnosed later in life have a high risk for health and psychiatric issues.
When autistics look for help, it’s mostly for mental health symptoms. When asking for an autism assessment, they are often ignored and dismissed.
A lot of times, the anxiety and depression are more debilitating than autism symptoms themselves.
Piven
He also uncovered that there is a high rate of Parkinson’s disease among autistic adults. 3 out of 19 autistic adults had Parkinson’s disease and 9 had symptoms of it. Piven also found 37 autistic adults 40-50 years old and 12 had symptoms of Parkinson’s disease.
This could be because Parkinson’s disease is caused by a lack of dopamine and ADHD is a common comorbidity and its also caused by a lack of dopamine. Upon further research, people with ADHD are 10 times more likely to get Parkinson’s disease.
The findings of this study does suggest that the diagnostic tools and processes need to be improved in order for people to be diagnosed much younger.
Getting diagnosed late in life is empowering after getting the official diagnosis for something that has been known all along. Autistic adults find each other through the internet and connect. They share similar stories and create strong bonds.
One adult autistic was diagnosed at 50 years old. her name is Anita Lesko. She says it was a revelation.
It was as if the whole puzzle of my entire life, all the pieces, suddenly fell together and made a whole picture
Anita Lesko
Anita is an anesthesia nurse and had been told she could be fired for not being a team player. She ate by herself and protested heavy metal music in the operating room. She found it distracting.
After being diagnosed, she was able to educate the staff about her behaviors. She realized there must be others like her and started a support group for autistic adults.
She then met Abraham Nielsen, a 25 year old anutistic man, and formed a close friendship.
We totally understand each other. We’re on the same wavelength.
Anita Lesko
After one and a half years, they took the friendship further. Anita won’t let anyone touch her except for Abraham.
We just can’t touch each other enough – hugging and romance and everything. No one else can come near me.
Anita Lesko
sources:
https://www.cbsnews.com/news/children-diagnosed-developmental-disability-autism-cdc-reports/
https://www.scientificamerican.com/article/the-real-reasons-autism-rates-are-up-in-the-u-s/
https://www.verywellhealth.com/when-did-autism-start-to-rise-260133
https://www.cdc.gov/media/releases/2023/p0323-autism.html
https://www.drakeinstitute.com/why-are-autism-rates-increasing
Number Diagnosed With Autism Jumps 787 Percent In Two Decades
https://onlinelibrary.wiley.com/doi/10.1002/aur.2808
Aviva Seigler 