Autism is a developmental and neurological disorder characterized by problems with communication and interaction with others, as well as repetitive behaviors or limited interests. (1) As the clinical term, autism spectrum disorder (sometimes just referred to as ASD) implies, autism is a condition that falls on a spectrum. In some individuals, problems with communication, interaction, and repetitive behaviors may all be severe. In others, the only impairment may be a mild one when it comes to interacting in social situations.
But it has only been recently that doctors identify everyone on the autism spectrum with just a diagnosis of autism.
In 2013, Doctors Stopped Diagnosing 4 Different Types of Autism
Until 2013, there had been four separate diagnoses within the category of autism: autistic disorder, Asperger's syndrome, childhood disintegrative disorder, and pervasive developmental disorder (PDD-NOS). The change was made because these distinct diagnoses were not always made consistently and may have limited treatment options for some individuals on the spectrum.
The American Psychiatric Association’s (APA) revision to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), published in May 2013, did not include four subtypes of autism. According to the DSM-5, anyone on the autism spectrum should be diagnosed simply with autism spectrum disorder. “The revised diagnosis represents a new, more accurate, and medically and scientifically useful way of diagnosing individuals with autism-related disorders,” the APA noted in a statement released with the DSM-5 revision. (2)
The change was made in part because these diagnoses were not consistently applied across the board, according to the APA. Doctors approached each of these diagnoses differently. Rolling the diagnoses into a single category offered a more cohesive approach to treating autism.
“The previous labels were applied very unevenly and did not separate subgroups in a reliable or meaningful way,” says Jeremy Veenstra-Vanderweele, MD, director of child and adolescent psychiatry at Columbia University College of Physicians and Surgeons in New York City. “Depending where someone went for an evaluation, they might walk out with a different diagnosis, even though the recommendations for treatment might be the same.”
He clarifies though that the switch to now putting everyone with autism in the same category does not mean that everyone gets the same treatment. The current standard for autism treatment is to tailor the plan to the individual’s symptoms and functioning, and to the care options available. ”We need to think about the individual with whom we are working and what his or her strengths and difficulties are,” Dr. Veenstra-Vanderweele says. The new categorization of autism makes it easier to do that.
“Autism requires us to have a range of different treatment approaches and treatments offered,” says Thomas Frazier II, PhD, chief scientist at Autism Speaks, an autism advocacy organization. Flexibility throughout the course of treatment is also important. “When a child is diagnosed early on, for instance, we still don’t know yet if that person is high-functioning or will have high cognitive difficulties. Intervention very much shifts dependent on the individual.”
Why the Old Definitions of Autism Were Flawed
The old autism subtypes did recognize that autism is very much a spectrum disorder, meaning different people experience different symptoms. But, there was a lot of grey area in determining what symptoms were most important for putting any one individual into one category versus the other. Veenstra-Vanderweele adds: “The shift to a single diagnosis of autism spectrum disorder reflects the reality that we don’t know how to split up the disorder into groups of people.”
The definitions of those four subtypes of autism help elucidate why the distinctions were not always clear and where there was overlap between the criteria for the different subtypes: (3)
Autistic Disorder This had been the broadest subtype of autism. Some considered it to characterize the “classic” case of autism. Symptoms could include any combination of language challenges, repeating specific behaviors, learning disabilities, or problems with speech and nonverbal communication. One individual with this diagnosis might have also had very unique strengths and differences from others.
Some of these people really have very specific interests that some might label as obsessive, Veenstra-Vanderweele says. Others categorized in this way might be unable to leave behind a topic in conversation, he adds.
Asperger’s Syndrome This diagnosis was given to people who were on the “high-functioning” end of the autism spectrum. Typically what distinguished Asperger’s from the other types of autism was having difficulty with social interactions and showing signs of repetitive behaviors. Some people with this diagnosis may have had problems with motor development, but typically individuals with the diagnosis did not have serious delays with language or other kinds of cognitive development.
Some with the diagnosis may have exhibited robotic and repetitive speech patterns, had difficulty in reading social or emotional cues or “nonliteral phrases,” or had difficulty making or maintaining eye contact during conversation. The condition was commonly diagnosed later in childhood, once a child started to have difficulties in a classroom setting (or sometimes, in the case of adults, in the workplace). (4)
Childhood Disintegrative Disorder Childhood disintegrative disorder (CDD), or “Heller’s syndrome,” was a rare diagnosis that by definition did not cause symptoms until later in childhood. Children appeared to develop normally, but at age 3 or older would start to have problems with motor skills, social interaction, or language. (5) A rare diagnosis, CDD was said to occur in about 1 or 2 out of every 100,000 kids. (6)
Pervasive Developmental Disorder (PDD-NOS) This condition had also been referred to as a type of “subthreshold autism” because a person could have shown some, but not all, of the characteristics of autism. Symptoms could have been fairly mild. Research has shown that many children diagnosed with this subtype of autism did not fit neatly into the category, but rather had quite different severity of symptoms when it came to language impairment, social skills, and repeated behaviors. (7,8)
The Criteria Doctors Use to Diagnose Autism Now
The current criteria for diagnosing autism haven’t changed — each former subtype of autism is still considered autism. Currently, to be given a diagnosis of autism, an individual needs to have problems with communication and interaction with other people or restricted interests and repetitive behaviors.
When given an autism diagnosis, the healthcare provider should also specify which of the following areas the individual has problems with:
- Intellectual problems, including those with reasoning or memory
- Problems with language or speech
- Another medical on genetic condition related to or contributing to autism, such as seizures or Fragile X syndrome
What About People Who Were Previously Diagnosed With a Specific Autism Subtype?
It’s important to know that if you were previously diagnosed with a subtype of autism, you do not need a new evaluation or a new diagnosis, Veenstra-Vanderweele explains. Your disability is simply considered autism spectrum disorder now, according to the guidelines.
You should get reevaluated (as should anyone with autism) if your symptoms have changed significantly, you’re having new difficulties, or if you’re not responding to treatment, according to Veenstra-Vanderweele. And of course if you have any concerns about your diagnosis — whether it’s an old one or a new one — you should talk to your healthcare provider.
It’s also important to recognize that the old autism subtype labels can be helpful and meaningful to some individuals for whom those terms have helped them understand their own disability. And just because doctors don’t use those labels in autism diagnoses anymore, it doesn’t mean they need to be scrubbed from every context, Veenstra-Vanderweele says.
“The term ‘Asperger’s' allowed some people to find a description of others whose experience was similar to their own, and in some cases, connect with a broader community of people,” he says. “This connection can be very helpful and I don’t think any of us would want to take that away from someone who finds it useful.”
The changes to how doctors diagnose autism are important for doctors to have “reliable diagnoses that are consistent across clinicians,” Veenstra-Vanderweele adds. That being said, for individuals or groups within the autism community who still identify with other labels, it’s okay that those terms still exist, he says. But it is important to understand their clinical limitations.