AuDHD Misdiagnosis and Co-occurring Conditions
Introduction
For many people, receiving an AuDHD diagnosis can be life changing. It can provide an explanation for a lifetime of experiences that may have felt confusing and help individuals better understand their strengths, challenges and needs.
However, many neurodivergent individuals experience a long journey before receiving an accurate diagnosis. Individuals may also be diagnosed with a mental health condition or receive support for difficulties that only explain part of their experiences prior to receiving a neurodivergent diagnosis.
In this research summary, we explore:
Common misdiagnoses prior to an AuDHD diagnosis
Similarities between AuDHD and some mental health conditions
How co-occurring conditions can complicate a neurodivergent diagnosis
Common Misdiagnoses Prior to an AuDHD Diagnosis
One reason AuDHD can be difficult to identify is that traits associated with autism and ADHD can sometimes resemble other mental health conditions.
ADHD is commonly mistaken for:
Anxiety disorders
Depression
Bipolar disorder
Borderline Personality Disorder (BPD)
Similarly, autistic individuals may initially receive diagnoses relating to:
Anxiety
Eating disorders
Obsessive Compulsive Disorder (OCD)
Borderline Personality Disorder (BPD)
In some cases, these diagnoses may accurately reflect difficulties that an individual is experiencing. However, misdiagnosis can occur for two key reasons. Firstly, co-occurring conditions may become the primary focus. Secondly, some autistic and ADHD traits can appear similar to symptoms seen in mental health conditions.
Similarities between AuDHD and Mental Health Conditions
Common ADHD traits:
Hyperactivity and restlessness
Difficulty concentrating
Emotional dysregulation
Low frustration tolerance
Temper outbursts
Daydreaming or “zoning out”
These traits can resemble presentations seen in anxiety, depression, bipolar disorder and personality disorders, making it difficult to distinguish between the two.
Common autistic traits:
Selective eating or sensory-based food preferences
Strong preferences for routine and predictability
Intense or highly focused interests
Difficulties with relationships and social interaction
Emotional dysregulation
Impulsivity (particularly where ADHD is also present)
These characteristics can sometimes be mistaken for eating disorders, OCD or personality disorders.
Importantly, while traits may look similar on the surface, the underlying reasons can be very different. For example, both autism and borderline personality disorder may involve difficulties in relationships - but autistic individuals commonly experience challenges linked to communication differences or overstimulation, whereas relationship difficulties associated with BPD are often linked to interpersonal and emotional factors.
This highlights the importance of neuro-affirmative assessments that explore a person's developmental history and lived experience rather than focusing solely on presenting symptoms.
Co-occurring Conditions and AuDHD
Whilst we have talked about the possibility of misdiagnosis in neurodivergent adults, research has consistently found that neurodivergent individuals are more likely to experience co-occurring mental and physical health conditions.
Common co-occurring conditions include:
Anxiety
Depression
OCD
Eating disorders
Personality disorders
Substance misuse
When these conditions are present, clinicians may just focus on the difficulties causing the greatest distress. However, this can sometimes result in diagnostic overshadowing, where an existing diagnosis is used to explain all of a person's experiences, leading to a misdiagnosis.
For example, autistic individuals with co-occurring conditions have been found to be diagnosed later than those with autism alone. It has been suggested that this may be due to the autistic traits being attributed to another condition rather than being recognised as part of a neurodevelopmental profile. Similar findings have been reported in ADHD research.
Whilst these conditions are often genuine and may require immediate support, recognising underlying autism and ADHD traits can improve outcomes and, in some cases, reduce co-occurring mental health difficulties.
Conclusion
Misdiagnosis can occur because many neurodivergent traits overlap with mental health conditions, and co-occurring conditions can further complicate assessments.
As awareness of AuDHD continues to grow, researchers and clinicians are developing a better understanding of these overlapping presentations. This is helping to improve recognition of AuDHD and supporting more accurate, neuro-affirmative assessments.
We’re here to help. If you would like to join our Peer Support Services, get access to a verified self- funded assessment or if you’re just looking for more information, get in touch today by emailing hello@audhduk.org
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