Is ADHD more common with autism in children of older parents? 

The relationship between autism, ADHD comorbidity and parental age is gaining growing attention from researchers and clinicians. While both conditions are common individually, there is increasing evidence that children born to older parents may be more likely to experience them together. 

The rise in studies on autism, ADHD comorbidity and parental age suggests that certain age-related genetic or epigenetic factors may contribute to this dual diagnosis. Children with both autism and ADHD often present with more complex co-occurring conditions, including challenges with executive function, impulsivity, and social communication. This neurodevelopmental overlap can complicate early detection and may require integrated treatment strategies. 

Why dual diagnoses might be more likely 

Here’s how autism, ADHD comorbidity and parental age may connect in clinical practice: 

Shared developmental pathways  

Genetic traits linked to older parental age may affect brain development in ways that increase the likelihood of both autism and ADHD. 

Broader co-occurring profiles  

Children with dual diagnoses often face additional co-occurring conditions, making diagnosis and support more complex due to the neurodevelopmental overlap between symptoms. 

Visit providers like Autism Detect for personal consultations to understand how maternal health and sensory processing may affect your child’s development and how to support effective sensory regulation and comfort. 

For a deeper dive into the science, diagnosis, and full treatment landscape, read our complete guide to Advanced Parental Age.

Hannah Smith, MSc

Author

Hannah Smith is a clinical psychologist with a Master’s in Clinical Psychology and over three years of experience in behaviour therapy, special education, and inclusive practices. She specialises in Applied Behavior Analysis (ABA), Cognitive Behavioural Therapy (CBT), and inclusive education strategies. Hannah has worked extensively with children and adults with Autism Spectrum Disorder (ASD), ADHD, Down syndrome, and intellectual disabilities, delivering evidence-based interventions to support development, mental health, and 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 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.