Understanding an Autism Diagnosis in Adulthood

An expert explains why more adults are seeking a diagnosis for autism spectrum disorder and what it means to receive one.

Around 5 million adults in the United States have autism, a lifelong developmental disability that affects a persons behavior, communication, and social interactions. Often, autism is diagnosed during childhood, which allows for early intervention and support through each phase of life.

However, some people may go undiagnosed into adulthood, research studies have found. Tallulah Willis, the 30-year-old daughter of Demi Moore and Bruce Willis, shared that she recently received an autism diagnosis, which she said changed her life. Studies show a trend of adults seeking an autism diagnosis in recent years, most likely due to more public awareness and because when left undiagnosed, there is an increase of co-occurring disorders, such as anxiety and depression.

“Many adults seek an autism evaluation due to difficulty transitioning into their next phase of life, whether its college or employment, or because they are having significant mental health challenges,” says Dr. Michelle Gorenstein-Holtzman, a clinical psychologist specializing in autism at NewYork-Presbyterian/Weill Cornell Medical Center. “Many parents seek an evaluation for themselves after their child has received a diagnosis and they recognize some of the same difficulties within themselves.”

Health Matters spoke with Dr. Gorenstein-Holtzman to better understand what it means to be diagnosed with autism as an adult.

What are the criteria to make an autism diagnosis?
Dr. Gorenstein-Holtzman: People diagnosed with autism meet the following criteria, according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5): 

  • Difficulty with communication and interaction.
  • Restricted interests and repetitive behaviors.
  • Symptoms that affect their ability to function in school, work, and other areas of life.

It is important to note that symptoms of autism present differently for everyone and vary from person to person. Symptoms can also look different throughout one’s lifespan.

For example, in terms of challenges with communication or interaction, difficulties in nonverbal communication is a core symptom of autism. Many adults have learned to look at people in their eyes when interacting. However, the quality of eye contact might be unusual, or they express that modulating eye contact is a very conscious process.

Another example is individuals have friends but might struggle with maintaining friendships. In children, we are thinking more about play skills, turn-taking and sharing. In adults, it is more about their ability to have socially reciprocal relationships — to have a back-and-forth conversation and display shared enjoyment. For example, if you watch a funny TV show, would they call their partner, or text a friend to say, ‘I just watched the funniest thing’ or do they usually prefer to keep the enjoyment to themselves? The core challenges are the same in childhood and adulthood, but how signs present are different.

What are some potential reasons why an autism diagnosis is missed earlier in life?
Our understanding of autism has developed over the years. Recently, we have learned more about autism in women and girls and how masking (or hiding symptoms) can lead to autistic burn out. We used to only give a diagnosis if we could observe behaviors, but we now understand that an individual’s internal experience is important when making a diagnosis.

"Many adults that I evaluate express relief to hear that there is a reason for their lifelong difficulties. It feels very validating."

— Dr. Michelle Gorenstein-Holtzman

We used to assume that an individual needed to show clinically significant behaviors early in development to get a formal diagnosis. However, while symptoms must be present in early childhood, difficulties might not become fully apparent until later in development when the social environment becomes more complex. Older generations had a different concept of autism and assumed that autistic individuals did not want social interactions and could not develop meaningful relationships. We now know this is not true. Many of our previous beliefs around autism, led to a significant number of missed diagnoses.

When making a diagnosis of autism, we are looking at a combination of symptoms and behaviors. Having a single symptom does not mean that someone has autism.  For example, an individual can struggle with eye contact as a result of social anxiety. Individuals might have sensory seeking behaviors due to ADHD. Many of us have experienced some of these symptoms and behaviors throughout our life but symptoms have not been consistent, or met the threshold for a diagnosis, or have impacted our functioning. As an adult, we may have had an awkward conversation where we did not know what to say or struggled to read a social situation correctly. The fact that these symptoms and behaviors can overlap with other diagnosis and are also experienced by many of us can also lead to a missed diagnosis in early life.

The Evaluation Process

According to Dr. Gorenstein-Holtzman, an evaluation typically consists of a thorough clinical interview and a formal autism assessment, as well as self-report measures. The clinical interview is conducted with the adult and someone who knows the person’s history (such as a parent, sibling, childhood friend, partner). “To make an accurate diagnosis, having a historian is important as we need to understand someone’s developmental history,” says Dr. Gorenstein-Holtzman.

The gold-standard autism assessment is the ADOS-2. “The ADOS-2 gives clinicians an opportunity to observe and evaluate someone’s social communication skills and restricted interests and repetitive behaviors,” says Dr. Gorenstein-Holtzman. “The ADOS-2 and the interviews allow clinicians to tease apart what we are observing versus the internal experience of an individual. We do not rely on one tool or assessment when evaluating adults for autism but rather try to gather information using a variety of methods.”

How does a diagnosis in adulthood impact an individual, especially after years of living without a diagnosis? And what kinds of support are there for adults?
Many adults that I evaluate express relief to hear that there is a reason for their lifelong difficulties. It feels very validating for them when we can say, this is their experience and there is an explanation for their difficulties. They also feel that they are finally being heard. For many individuals getting a diagnosis also means getting access to accommodations and resources.

For autistic adults who need significant supports and struggle with daily living skills, there are state and federal programs that offer a range of services. For adults who are more independent, a diagnosis leads to an increase in accommodations in school and in the workplace. There are also online and in-person programs for autistic adults. Getting a diagnosis and learning about resources and programs gives many adults who I work with a sense of community and belonging.

What should people keep in mind if they would like to seek a diagnosis?
It is important to find somebody who is an expert in autism in adults. That can be a clinical psychologist, psychiatrist, or neurologist, somebody who gets the nuances and is able to look at the whole clinical presentation. Autism does not just pop up in adulthood. There would be symptoms or signs early in development, even if they did not raise significant concern until later on. Adults seeking an autism evaluation should not go into the appointment certain of a diagnosis based on online quizzes or social media.

Michelle Gorenstein-Holtzman, Psy.D., is a clinical psychologist specializing in autism at NewYork-Presbyterian/Weill Cornell Medical Center. She is also an assistant professor of psychology in clinical psychiatry at Weill Cornell Medicine. At the Center for Autism and the Developing Brain, Dr. Gorenstein-Holtzman specializes in adult diagnostic evaluations. She also leads evidenced based social skills groups for autistic adults.  

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