Autism in Adults: Signs, Diagnosis and Treatment

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While diagnosis of Autism Spectrum Disorder (ASD) is most often in children and toddlers, it’s possible for people to not receive a diagnosis until well into adulthood.

Key Points

  • As awareness of ASD has increased, more adults are being diagnosed with autism later in life
  • There currently isn’t a generally accepted set of criteria to diagnose adults with ASD
  • Adults with ASD may find it harder to receive a diagnosis but there are plenty of treatment options available

If you think you or someone you know might be on the autism spectrum, then this article will explain the symptoms and traits associated with ASD, how an adult can receive a diagnosis, and what treatment is available.

What are the signs of autism?

Autism is generally identified with social and communication difficulties and repetitive behaviours but these signs can be quite mild, and some people have learnt to disguise them quite well.

ASD is commonly diagnosed in the first two years of a child’s life, but some individuals may not be diagnosed until much later in life.

Signs of autism occur in three main areas:

  • Social interactions
  • Verbal and nonverbal communication
  • Repetitive or ritualistic behaviours

Some adults with autism may show symptoms that resemble Attention Deficit Hyperactivity Disorder (ADHD), whereas others may have symptoms like impaired spoken language.

This is why it’s called the Autism Spectrum Disorder – there is a whole range of symptoms and people display them and experience autism in their own unique way.

For example, some people may feel like something is “different” about them. They might notice they feel or behave differently, but others around them do not notice they behave or act differently. Others who experience ASD may experience symptoms that make daily life extremely difficult.

No matter how ASD manifests, the symptoms of autism can pose challenges in everyday life.

As the understanding of autism improves, more people than ever are being diagnosed with ASD and receiving a diagnosis later in life.

What are the symptoms of ASD in adults?

It’s not uncommon for an adult living with autism to have gone through life without a diagnosis – often saying they had a feeling they just didn’t quite “fit in”.

It’s also common to hear stories about people seeing something or reading stories about autism and thinking to themselves “that’s me”. They may then choose to talk to a health professional for a diagnosis, or they may not.

While no two people with ASD are the same, and symptoms can manifest in a number of ways, some common symptoms of autism in adults include:

  • Difficulty interpreting what others are thinking or feeling
  • Trouble interpreting facial expressions, body language, or social cues
  • Difficulty regulating emotion
  • Trouble keeping up a conversation
  • Difficulty maintaining the natural give-and-take of a conversation; prone to monologues on a favourite subject
  • Tendency to engage in repetitive or routine behaviours
  • Only participates in a restricted range of activities
  • Strict consistency to daily routines; outbursts when changes occur
  • Exhibiting strong, special interests

Although ASD is typically a life-long condition, diagnosis and treatment can make a huge difference in living with your autism. Especially when you realise challenges you have faced in work or life have happened because of your autism.

Diagnosis of autism in adults

There are currently no standard diagnostic criteria for adults with suspected ASD, but they are in development.

In the meantime, clinicians primarily diagnose adults with ASD through a range of in-person observations and interactions. They will also take into consideration any symptoms a person reports experiencing.

Because most autism diagnoses are made in children, it could be a challenge to find a provider or health professional who will diagnose adults.

If your clinician determines that you didn’t display symptoms of ASD in childhood, but instead began to experience symptoms as a teen or adult, you may be evaluated for other possible mental health or affective disorders.

Why the later diagnosis?

Typically, adults who receive a late autism diagnosis have less noticeable symptoms – previously this may have been called ‘Asperger’s syndrome’ which now comes under the ASD banner.

Growing up, you may have experienced:

  • Being unable to read body or facial language such as someone frowning
  • Taking sarcastic comments literally or not understanding playground jokes – when told to ‘get lost’ they may have literally tried to ‘get lost’
  • Difficulty making friends, with some preferring to play alone or with older children or adults
  • Narrow interests and wanting to find out everything there is to know about a topic
  • Using a formal style of speaking
  • Sensory sensitivity to loud noise, bright lights, or strong flavours
  • A dislike of change – instead preferring routines and rituals
  • Avoiding eye contact when speaking, or at times staring at others
  • Difficulty expressing wants, needs, and opinions, or using appropriate grammar and vocabulary

As people move into their adolescence and especially into adulthood, they may find their lives are still impacted in different ways, but often people learn social skills and how to read social cues. People living with autism grow up to have strong careers, marry, and have children.

You may choose to seek an autism diagnosis if:

  • You have been diagnosed with a mental health condition or intellectual disability during childhood or adolescence, but think that you may have autism
  • You have struggled with feeling socially isolated and different
  • Your child or other family member has been diagnosed with autism and some of the characteristics of autism sound familiar to you.

So, where to if you are seeking a diagnosis?

Seeking a diagnosis is completely up to the individual but if it’s something you or someone you know would like to explore, the best first step is to talk to your General Practitioner (GP).

Your GP will usually refer you to a Clinical Psychologist or Psychiatrist for consultation. From there, you’ll generally be asked lots of questions about your childhood, experiences at school, and the present day. They may also do some psychological or psychiatric testing before making a formal diagnosis.

A Speech Pathologist (also known as a Speech Therapist) may also be consulted to assess your social communication skills. All of this information will be used to help make a diagnosis.

It’s important to remember that autism is a complex disability and as far as the current research is concerned, there’s no single cause. Instead, it’s likely to be due to a combination of environmental and genetic factors.

It’s also possible you may be eligible for NDIS funding. If you are assessed as having ASD at level 2 (requiring substantial support) or level 3 (requiring very substantial support), you may qualify for NDIS funding.

However, not all individuals with Autism Spectrum Disorder will be approved for NDIS funding, particularly those with milder forms of ASD that have been diagnosed later in life.

For further details and information on eligibility, head to the NDIS website.

Living with an autism diagnosis

Receiving an autism diagnosis as an adult can be a challenging one but it can also be quite a freeing feeling.

Many adults who receive an ASD diagnosis as an adult say they experience a greater understanding of themselves and how they relate to the world.

A diagnosis can help you gain a different perspective on your life experiences and help those around you understand and empathise with your unique traits.

Better understanding the set of challenges you face can help you find new and inventive ways to work with or around those challenges.

How is autism in adults treated?

Adults aren’t typically given the same treatments as children with ASD. Some adults may be treated with cognitive, verbal, and behavioural therapy.

It may also be common to seek out treatments for specific challenges you could potentially experience, such as anxiety, social isolation, job difficulties, or relationship issues.

Some potential treatments for challenges you experience include:

  • Seeking a psychiatrist experienced in autism treatment for medical evaluation
  • Consulting a psychologist or social worker for group and individual therapy
  • Receiving counselling on an ongoing basis
  • Seeking career help

Many adults with autism find support through online groups and forums, as well as connecting with other adults on the autism spectrum in person.

If you, or someone you know, seek autism treatment as an adult, then it can actually improve your quality of life moving forward. While it’s not common for adults to be diagnosed with ASD in their older years, more adults are asking to be evaluated for autism.
As awareness of ASD continues to grow, the diagnosis and treatment of adults with autism will only improve.

Have you or someone you know been diagnosed with ASD as an adult? Let us know in the comments below.

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