How Common is Autism/ADHD Comorbidity?

PostedNovember 12, 2025

UpdatedNovember 12, 2025

ByMy Patient Advice

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

Autism ADHD comorbidity is far more common than previously thought. Studies show that a large percentage of individuals diagnosed with one condition also meet criteria for the other. These co-existing conditions often go unrecognised at first, leading to incomplete or delayed diagnoses. Understanding how often they occur together helps improve assessment and support planning.

According to current prevalence rates, between 30% and 70% of people with autism also have ADHD, and around 20% to 50% of people with ADHD may also be autistic. These diagnosis statistics are supported by research showing shared genetic, neurological, and behavioural traits. However, the overlap can make it challenging for clinicians to tease the conditions apart without a thorough evaluation that considers both profiles equally.

Key Signs in Co-occurring Cases

Here are some common signs seen in individuals with both autism and ADHD that highlight the complexity of comorbidity:

Fluctuating Focus

ADHD often brings general distractibility, while autism may cause hyperfocus on specific interests, both can exist simultaneously in a person.

Emotional Regulation Difficulties

Both conditions can lead to intense emotional responses, but autism may include sensory overload while ADHD reactions are more impulsive.

Challenges with Routine and Organisation

Autistic individuals may prefer strict routines; those with ADHD may struggle to maintain them. Together, this can create a push-pull dynamic in daily life.

Recognising the high rate of autism ADHD comorbidity helps ensure that assessments and interventions are accurate and holistic.

Visit providers like Autism Detect for personal consultations.

For a deeper dive into the science, diagnosis, and full treatment landscape,read our complete guide to misdiagnosis and differential diagnosis.

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.