Autism: What is it and how is it diagnosed in adults?

What is Autism and how is it diagnosed in adults

Autism is a lifelong developmental condition that affects how people communicate and interact with the world. Most diagnoses are made in early childhood, but as the disorder becomes more understood, it is now common for adults to receive a diagnosis in adulthood.

Professor Mandy of University College London points out that later-diagnosed individuals can have milder problems in early childhood, perhaps giving an understanding of why some diagnoses occur much later.

“Life becomes more and more complex as one gets older. Times of transition can be particularly demanding, such as starting secondary school, university or a new job. At these times, social and behavioural differences can become more evident as the individual responds to the social and educational challenges of school, work and friendships.”

There are many benefits to receiving a diagnosis. It can give hope and help the individual understand why they may have felt different from those around them or help to explain why they have struggled with other mental health issues like depression or anxiety. A diagnosis can help determine which interventions and treatment options may be available or valuable for the individual. Receiving a diagnosis later in life can still provide reassurance that the individual’s situation is not unique or inexplicable, offering peace of mind for unexplained situations that have happened throughout the individual’s life. It can also help reduce stigma by explicitly acknowledging the presence of Autism.

When Autism is diagnosed later, the individual may struggle more to accept their diagnosis as they haven’t had years of support to understand it. It can also trigger feelings of loss and sadness, especially if they have had lots of difficulties related to Autism without an awareness of the disorder.

Reasons behind a late diagnosis of Autism

Signs of Autism occur on a spectrum; it is often noted that no two individuals with Autism have the same profile. It is more common to get a late diagnosis if the individual has not had trouble academically, but as academic and social pressures increase and social rules become more complex, individuals with Autism may experience problems when previously they had not. Also, higher intelligence and good language skills can mean an individual can mask or find solutions to many difficulties.

Females are more likely to receive later diagnoses than males, as it is easier to identify in males. Females tend to be better at compensating for social difficulties. Individuals may have been diagnosed with other related diagnoses, like ADHD, OCD, Social Anxiety Disorder, or depression.


The signs of Autism may present later with:
  • Problems forming friendships perhaps finding it easier to form friendships online
  • Expressing feelings of not fitting in 
  • Social withdrawal and isolation
  • Being easily overwhelmed by sensory input or in crowded places
  • Difficulty expressing emotions 
  • Academic challenges in areas of abstract thinking and time management
Diagnosing Autism in Children vs. Adults

Diagnosis depends on compiling a personal history that links together all the available information. Ideally, this information is collected systematically from parents or an informant who can share information about developmental milestones and behaviour in infancy. The interviewer will use a schedule of questions to diagnose autism spectrum disorders so that all critical details are covered. This interview takes time, at least 2-3 hours. The diagnosis can be missed if this is rushed or a schedule is not used.

The second part of the assessment involves ‘The Autism Diagnostic Observation Schedule, Second Edition (ADOS-2)’, which is a standardised observational assessment of communication, social interaction and play or imaginative use of materials. 

It differs from the first part of the assessment, where the diagnostic tools are based on developmental information and instead only looks at current behaviour and skills. It can be used to evaluate individuals of all ages across different developmental levels. 

Diagnosing Autism in adults, in some cases, can be more challenging due to missing viewpoints. For example, parents may be absent or distant in adulthood and may not clearly recall early milestones. 

Adults may have also learned to hide or conceal issues. This can present a challenge with diagnosis as they’ve spent their lives correcting or covering these problems, and it can be tough to see the underlying issues.

The positives of Autism in the workplace

People with Autism or autistic spectrum disorders have a specific mental toughness, focus, and attention to detail, which can benefit people in their early life or later life, especially at work. Keenness to listen and learn about Autism should also be appreciated as those diagnosed with Autism bring valuable skills that businesses can benefit from in their workplace culture. 

Individuals with Autism or autistic spectrum disorders also possess their own creative expression and imagination that could bode well in the workplace when employees are expected to think outside the box in specific situations.

If you think you or someone you know has Autism, please contact Onebright to discuss your needs.

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