- The signs of autism in adults include difficulty making friends, preferring to be alone, and anxiety.
- Appearing blunt and having ritualized patterns of behavior may also be symptoms of autism.
People with autism spectrum disorder (ASD) may behave and interact differently from most people. They often have repetitive behavior, difficulty communicating, and strong or intense interests in specific topics or objects.
However, that doesn't mean having autism is always debilitating or that people with autism cannot lead independent lives. The term "spectrum" means that there is a wide range of symptoms, skills, and levels of function among people with autism and it's not the same for everyone.
Signs of autism usually appear before the age of three, but some people with autism might not get diagnosed until they reach adulthood, which makes it challenging to get the support they need.
Today, more than five million adults in the United States have ASD. There aren't good estimates on how many people with autism reached adulthood without a diagnosis, says Dr. Christopher Hanks, medical director of The Center for Autism Services and Transition (CAST) at The Ohio State University Wexner Medical Center.
Here are the signs of autism in adults and how healthcare providers generally diagnose it.
Signs of autism in adults
The signs that lead to a diagnosis of ASD are the same for children and adults, says Wayne Fisher, director of the Rutgers University Center for Autism Research, Education, and Services (RU-CARES).
Some signs of autism in adults include:
- Difficulty understanding what others are thinking or feeling
- Having very ritualized patterns of behavior and getting anxious if these rituals are interrupted
- Appearing blunt or rude without meaning to
- Not understanding social cues
- Difficulty making friends
- Preferring to be alone
- Having high levels of focus or interest in certain topics or activities
- Not knowing how to express yourself
- Anxiety in social situations
Why some people aren't diagnosed until adulthood
People with autism are usually diagnosed in childhood. However, some people do not get diagnosed until their adulthood due to various factors.
1. Behavioral signs were not evident
Sometimes, signs of autism may not become obvious until much later in childhood or adulthood when certain demands increase.
For instance, if you struggle to interpret subtle communication cues, the symptom may only become more recognizable later on in situations such as employment or dating, says Hanks.
2. Autism in females often flies under the radar
The diagnostic criteria for autism are the same for males and females.
However, the knowledge and conceptualization of autistic traits were largely derived from male samples, which can lead to a skewed understanding of the autism spectrum.
Compared to males, females with autism tend to have:
- Lower likelihood of externalizing behaviors like breaking rules, disrupting activities, or interrupting others
- Higher social motivation, which means their social experiences can sometimes be more similar to individuals without autism than males with autism
- A greater capacity for traditional friendships
- Lower measures of repetitive behavior
- Better non-verbal communication
In other words, females may express their autism differently and fail to meet the diagnostic criteria. This might explain why autism is underdiagnosed in females and is more likely to be identified late, mislabelled, or missed entirely.
3. Lack of access to healthcare services
In the United States, autistic traits are underrecognized in racial or ethnic minority groups and people with low socioeconomic status, Hanks says.
These groups of people face several potential barriers to an autism diagnosis, which include:
- Lack of access to healthcare due to non-citizenship
- Lack of access to healthcare because of low income
- English is not their primary language
"I have seen adults with undiagnosed ASD more often in rural areas without ready access to autism experts," Fisher says.
How to diagnose autism in adults
A psychologist or psychiatrist will often interview you to learn about the history of your autistic traits and observe how you respond, Fisher says. They will ask about the way you communicate with others and whether you have any strong, specific interests, repetitive behaviors, or sensory issues. These questions will help them see if you fit the criteria for ASD.
Diagnostic tools like the Autism Diagnostic Observation Schedule — which is considered the gold standard in diagnosing ASD in adults — are often used to structure and guide the assessment, Fisher adds. This diagnostic test takes about 40 to 60 minutes to administer.
The diagnostician may also want to interview family members as well to get insight into your childhood experiences, Hanks says.
Ultimately, the decision to get diagnosed depends on you. If you are distressed about certain aspects of your behavior and you're questioning whether you might have ASD, getting a diagnosis could lead to appropriate treatment, support, and services, Fisher says.
"Many adults who have been diagnosed with autism report it helps them to understand themselves and be more self-aware of their areas of challenge," Hanks says.
How to treat autism in adulthood
There's no one-size-fits-all treatment plan because people with autism have different experiences. Treatments are often aimed at reducing challenges that interfere with their quality of life or daily function.
According to Hanks, the following therapies may be helpful for adults with autism:
- Speech therapy, for individuals who have trouble communicating or interacting with others.
- Psychotherapy, to help with mental health conditions.
- Occupational therapy, for people who have difficulty processing sensory information like sounds and textures or those who struggle with independence.
"Unfortunately, the availability of treatment, support, and services for adults with ASD is substantially less than for children," Fisher says.
There are plenty of interventions for children with autism because their brains are still forming compared to that of older ages, therefore treatments are more likely to be effective.
"Our field has become increasingly aware of the need to expand and improve adult autism services, and the situation is getting better, but much more needs to be done," Fisher says.
Insider's takeaway
Although the signs of autism are the same for children and adults, some people may have a delayed diagnosis because they did not have access to healthcare services or their autistic traits were not recognized.
For people with autism, getting a diagnosis may lead to a better understanding of oneself and better access to various therapies.
"We still have a lot to learn about those who are diagnosed as adults. This is an under-studied group," Hanks says.