Does Diagnostic Overshadowing Affect Adult Autism?

PostedNovember 6, 2025

UpdatedNovember 6, 2025

ByMy Patient Advice

Author: Beatrice Holloway, MSc | Reviewed by: Dr. Rebecca Fernandez, MBBS

Diagnostic overshadowing in autism is a phenomenon where other mental health or medical conditions overshadow the recognition of autism. In adults, this can lead to symptom’ misattribution, where traits of autism are misinterpreted as symptoms of other mental health issues. This often results in an adult diagnosis delay, as doctors may focus on the more obvious or widely known conditions, missing the underlying autism.

In diagnostic overshadowing, the healthcare provider may attribute an individual’s struggles with social interactions, emotional regulation, or repetitive behaviours to conditions such as ADHD. This is often due to medical bias or a lack of awareness that autism can manifest subtly in adults, especially in those who have developed masking behaviours to cope with their condition. As a result, many adults go undiagnosed, which can significantly affect their quality of life.

Common Symptoms of Diagnostic Overshadowing in Adult Autism

The common symptoms of diagnostic overshadowing in adult autism are as follows:

Social Withdrawal and Anxiety:

While adults with autism often struggle with social interactions, this can be mistaken for social anxiety or depression. Therapy focusing on building social skills and addressing anxiety can help individuals manage these challenges more effectively.

Repetitive Behaviours and Routines:

Adults with autism often engage in repetitive actions or follow rigid routines, which can be misdiagnosed as obsessive-compulsive disorder (OCD). CBT can help manage these behaviours by teaching individuals healthier coping mechanisms.

Sensory Sensitivities:

Overreaction to certain sensory stimuli, such as noise or light, may be attributed to other conditions like sensory processing disorder. Sensory integration therapy can help address these sensitivities and improve daily functioning.

For personalised support, visit providers like Autism Detect for personal consultations tailored to your needs.

For a deeper dive into the science, diagnosis, and full treatment landscape, read our complete guide to late diagnosis in adults.

Beatrice Holloway, MSc

Author

Beatrice Holloway is a clinical psychologist with a Master’s in Clinical Psychology and a BS in Applied Psychology. She specialises in CBT, psychological testing, and applied behaviour therapy, working with children with autism spectrum disorder (ASD), developmental delays, and learning disabilities, as well as adults with bipolar disorder, schizophrenia, anxiety, OCD, and substance use disorders. Holloway creates personalised treatment plans to support emotional regulation, social skills, and academic progress in children, and delivers evidence-based therapy to improve mental health and well-being across all ages.

All qualifications and professional experience stated above are authentic and verified by our editorial team. However, pseudonym and image likeness are used to protect the author's privacy.

Dr. Rebecca Fernandez, MBBS

Reviewer

Dr. Rebecca Fernandez is a UK-trained physician with an MBBS and experience in general surgery, cardiology, internal medicine, gynecology, intensive care, and emergency medicine. She has managed critically ill patients, stabilised acute trauma cases, and provided comprehensive inpatient and outpatient care. In psychiatry, Dr. Fernandez has worked with psychotic, mood, anxiety, and substance use disorders, applying evidence-based approaches such as CBT, ACT, and mindfulness-based therapies. Her skills span patient assessment, treatment planning, and the integration of digital health solutions to support mental well-being.

All qualifications and professional experience stated above are authentic and verified by our editorial team. However, pseudonym and image likeness are used to protect the reviewer's privacy.