| Last month, the Centers for Disease Control and Prevention announced what many people see as a startling rise in reported cases of autism over its now 25 year long monitoring study of autism in America. This most recent data from the program (called the Autism and Developmental Disabilities Monitoring Network - ADDM) seems to indicate the incidence of autism among 8-year-olds in the United States had risen from one in 150 in 2000 to one in 31 now.
The media is full of emotional responses to that announcement. To some concerned parties, the growth in the published numbers suggests we are having an autism epidemic. Some of these same people believe that it is preventable, and that unhealthy environmental factors are the main cause. Autism can be eradicated, they propose, if we isolate the pollution in our surroundings and remove it.
The use of the word "epidemic" may also be stimulating unconscious fears of contagion that are still too convincing in the wake of Covid, and lead to further misunderstanding.
Many of these widely held perceptions are wrong.
Describing the reported growth in autism from 1:150 in 2000 to 1:31 in 2022 ignores the many changes in the way the meaning of the word Autism has been defined medically, the growth in tools now available to detect it, and improvements in documentation over the last 25 years.
25 years ago we could not see what we now can. Science has helped make the invisible visible.
A More Informed Understanding of the reported growth in the number of Autistics.
Since ADDM's surveys began in 2000, the definition of 'autism' has expanded significantly several times to include a broader cluster of symptoms and presentations. With the release in 2013 of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), the term "autism" became shorthand for a more inclusive category referred to as "Autism Spectrum Disorder" (ASD).1 Separate diagnoses such as Asperger’s Syndrome, Childhood Disintegrative Disorder, and Pervasive Developmental Disorder–Not Otherwise Specified (PDD-NOS) were consolidated under that "Autism Spectrum Disorder" (ASD) label and regarded as variations within the spectrum.2 At the same time, scientists discovered correlations with other conditions like anxiety, ADHD, and sensory processing difficulties, again widening the population defined as having "Autism".
As researchers learned more, frontline clinicians took that new knowledge and gained more insight and better guidance about how to recognize autism among different ages, genders, and cultural backgrounds. Also, new diagnostic tests were invented which confirmed a more extensive set of indicators, including genetic testing, which seems to show that autism is between 60 and 90 percent inherited. And in up to 40 percent of cases, doctors can find a specific set of genetic mutations to explain the condition. All of these tools educated the public, which inspired stronger support services and greater awareness, which appears to have contributed to more parents having their kids checked out by a doctor.3
Each of these changes led to the perception of a skyrocketing rate. The following explanations for ASD represent the current scientific consensus about causes:
- genetics;
- toxins--lead, pesticides and air pollution;
- maternal factors--advanced age, auto-immune conditions, diabetes and obesity;
- prenatal and natal events--poor nutrition, premature birth, and oxygen deprivation during birth; and
- a complex interaction of any or all of the above.
ASD's Impact
Whatever its origins, ASD has had significant implications for education, employment and quality of life. Its most apparent signs include unusual social interactions, restricted interests, repetitive behaviors, sensitivity to sensory stimuli and poorly regulated emotions. In addition, many children with ASD, which occurs 3 to 4 times more frequently in boys, are troubled by less observable cognitive challenges. In school, comprehension and the ability to communicate may be inhibited by delays in language skills such as the expansion of vocabulary, speech articulation, and proper use of grammar. Information processing may be slower, too, disrupting memory and the ability to carry out instructions. In teenagers and adults, ASD also may interfere with executive functions such as planning, organizing and problem-solving, as well as higher-order skills that enable abstract and critical thinking.
Educators, employers, and parents of individuals with symptoms can learn more below.
1 ASD is sometimes also called Autism Spectrum Condition (ASC).
2 The International Classification of Diseases, 11th Revision (ICD-11), which took effect globally in 2022, aligns closely with the DSM-5 definition and further emphasizes the importance of considering individual functional abilities and support needs rather than relying solely on symptom severity.
3A neurodiversity framework recognizes autism as a natural variation in human neurobiology rather than solely a disorder to be "treated." This shift, too, has made diagnosis and support services more socially acceptable. |
