Diagnostic overshadowing and how it impacts on people with a learning disability and autistic people

Diagnostic overshadowing occurs when clinicians or caregivers attribute a person's symptoms or behaviours to their autism and / or learning disability diagnosis without considering other potential causes, such as medical conditions, mental health issues, or other neurodevelopmental conditions.

This can particularly affect people with a learning disability or autistic people because their behaviour can be misunderstood. It is important that council staff working with people for these groups are aware this could be an issue so that they can avoid misinterpreting people’s behaviour.

The National Institute of Clinical Excellence (NICE) defines diagnostic overshadowing as “the tendency to attribute all behavioural, emotional, physical and social issues to a person's learning disability or a pre-existing condition, while overlooking the possibility that they could be symptoms of other conditions or difficulties. An example would be attributing challenging behaviour to a learning disability when it could be a reaction to abdominal pain, which in turn might be symptomatic of a physical health problem.”

Diagnostic overshadowing was first defined in 1982, by Psychologist Steven Reiss. He noted that people with psychiatric needs often have their symptoms minimalised or dismissed as being part of their disability. This prevents thorough assessment of their needs and their needs being appropriately met.

• An autistic person or person with a learning disability experiencing anxiety or depression might have their symptoms attributed solely to their autism and / or learning disability, rather than being evaluated for a potential co-occurring mental health condition.
• A change in behaviour might be attributed to the autism / learning disability diagnosis without exploring possible medical causes, such as pain or illness.

Council staff such as social workers or occupational therapists and other care/support givers need to be aware of diagnostic overshadowing to ensure that autistic people and people with a learning disability receive comprehensive and appropriate care.

• Understanding that all behaviour is communication: The idea that "all behaviour is communication" is a helpful framework for understanding people with a learning disability and autism, as it emphasises that behaviours, even seemingly challenging ones, can be signals of unmet needs or difficulties in being understood. At the same time while the phrase "all behaviour is communication" is a crucial starting point, it is important to note that not all behaviours are intended as communication, and some behaviours, like stimming, are for self-regulation or sensory input. This is where it is important to use a functional analysis approach (Functional Behaviour Analysis (FBA) is a process used to understand why a specific behaviour is occurring, particularly challenging behaviours, in order to develop effective interventions. It involves gathering information about the environment, antecedents (events leading up to the behaviour), and consequences by a person with knowledge and experience in Autism and Learning Disabilities to discern between the two.
• Thorough assessments: Conduct comprehensive assessments to identify all potential causes of a person's symptoms, not just the autism / learning disability diagnosis.
• Consider co-occurring conditions: It is essential to recognise that autistic people and people with a learning disability can have other conditions, and to screen for them appropriately.
• Focus on the person: Focus on the individual's needs and experiences, rather than just the diagnosis.
• Collaboration: Working with a multidisciplinary team, including specialists in learning disabilities, autism, mental health, and other relevant areas, can help ensure comprehensive care.

Anxiety disorders

• Generalised Anxiety Disorder (GAD): Excessive worry and anxiety about everyday situations, lasting for at least six months.
• Panic Disorder: Sudden, intense episodes of fear or panic attacks, often with no apparent cause.
• Specific phobias: Intense and persistent fear of specific objects or situations.
• Social Anxiety Disorder: Intense fear of social situations and scrutiny by others.

Symptoms of anxiety disorders

Excessive worrying, restlessness, difficulty concentrating, muscle tension, irritability, and physical symptoms like rapid heartbeat, sweating and nausea.

What you may see in people with a learning disability and / or autistic people with anxiety disorders:

• cyclical thinking and repeating the same story / incident frequently
• intense focus on areas of worry – burglars / tsunamis / earthquakes / dying
• change in behaviour
• withdrawal / isolation
• decrease In appetite
• aggressive physical or vocal outbursts
• extreme fight or flight responses
• disturbed sleep
• repetitive behaviours / rocking / switching things on and off / opening and closing doors
• pacing / sleep disturbances / pai in body /grinding teeth / excessive eye rubbing / excessive stimming type behaviours
• rapid heartbeat – could cause crying / distress / self-injury / running away
• nausea could cause decreased or increased appetite.
• sweating could cause extreme changing of clothes / washing frequently / stripping.

Depression

• Persistent low mood: Feeling sad, empty, or irritable for prolonged periods.
• Loss of interest or pleasure: Difficulty finding enjoyment in activities that were once pleasurable

Symptoms of depression

Fatigue, changes in appetite or sleep, difficulty concentrating, feelings of hopelessness or worthlessness, and suicidal thoughts.

What you may see in people with a learning disability and / or autistic people with depression

• persistent crying
• increased/decreased appetite
• withdrawal/social isolation
• sleeping more
• anger/aggressive outbursts.

Obsessive-compulsive disorder

The main factor in determining if behaviour is autistic repetitive and restrictive behaviours and interest, or OCD, is being able to determine if the repetitive behaviour is driven by it feeling good and making the individual feel happy and content (which would suggest autistic stimming or repetitive behaviour), or if it is driven by a compulsion or urge that causes distress / the person feels if they don’t repeat behaviours something bad will happen / the behaviour reduces feelings of anxiety. The latter would suggest OCD – obsessive compulsive disorder. repeat behaviours something bad will happen / the behaviour reduces feelings of anxiety. The latter would suggest OCD – obsessive compulsive disorder.

• Obsessions: Persistent, unwanted thoughts, images, or urges that cause distress.
• Compulsions: Repetitive behaviours or mental acts that a person feels driven to perform to reduce anxiety.
• Symptoms: Excessive washing, checking, counting, or ordering, or having intrusive thoughts that are difficult to control.

What you may see in people with a learning disability and / or autistic people with obsessive-compulsive disorder

• Extreme distress when repetitive behaviour interrupted
• Behaviour appears to cause distress or anxiety
• Behaviour stops other things individual normally enjoys and does regularly
• Behaviour has changed in frequency, duration, intensity and focus.

Post-Traumatic Stress Disorder (PTSD)

Autistic people and people with a learning disability may experience trauma more frequently and from lesser events than neurotypical people such as school trauma or medical trauma. Autistic people may be more likely to find certain situations, events and experiences more traumatic than neurotypical people because of autistic traits such as: sensory sensitivities; communication and social interaction differences; distress around changes to routines; distress if environment does not meet needs like ability to stim or follow set repetitive routines. Also, where in the external environment around the person there is a lack of understanding around autism both by people and systems this can lead to traumatic experience in environments that are more tailored for a neurotypical experience. See NAS Post-traumatic stress disorder in autistic people.

• Develops after experiencing or witnessing a traumatic event.
• Symptoms: Flashbacks, nightmares, avoidance of reminders of the trauma, negative thoughts and feelings, and hypervigilance.

What you may see in people with a learning disability and / or autistic people with PTSD

• Extreme reaction to noise or sudden unexpected movement
• Disturbed sleep / nightmares
• Avoidance of bed / bedroom / sleep
• Extreme reaction to specific trigger – places / people / journeys / music / TV programme

Bipolar disorder

• Characterised by periods of extreme highs (mania) and lows (depression).
• Symptoms: During manic episodes, people may experience increased energy, rapid speech, racing thoughts, and poor judgment. During depressive episodes, symptoms are like those of depression.

What you may see in people with a learning disability and / or autistic people with bipolar disorder

Periods of hyperactivity followed by periods of extreme lethargy – sleeping. 

• Impulsive behaviours
• Increased spending
• Isolation / withdrawal
• Increased / decreased appetite
• Periods of sadness / crying 

Above will occur in clear cycles

Schizophrenia

• A chronic, severe mental disorder that affects a person's ability to think, feel, and behave clearly.
• Symptoms: Hallucinations, delusions, disorganised thinking and speech, and reduced emotional expression.

What you may see in people with a learning disability and / or autistic people with schizophrenia

• Self-injury particularly around ears / eyes / head
• Interaction with hallucinations – talking to / gesturing to empty spaces.
• Isolation / withdrawal
• Increased / decreased appetite
• Periods of sadness / crying
• Disturbed sleep / nightmares
• Avoidance of bed / bedroom / sleep
• Avoidance of certain areas / activities – e.g.: watching TV / listening to radio
• Reduced emotional response based on baseline presentation
• Risky / dangerous behaviours
• Impulsive erratic behaviours

Personality disorders

• Characterised by inflexible and unhealthy patterns of thinking, feeling, and behaving
• Symptoms: Difficulty with relationships, emotional instability, impulsivity, and distorted perceptions of reality.

What you may see in people with a learning disability and / or autistic people with personality disorders

• Isolation / withdrawal
• Increased / decreased appetite
• Periods of sadness / crying
• Disturbed sleep / nightmares
• Avoidance of bed / bedroom / sleep
• Reduced emotional response based on baseline presentation • Risky / dangerous behaviours
• Impulsive erratic behaviours -e.g.: fire setting / increased risky sexual behaviours
• Intense mood swings – rapid cycling
• Intense fixation on areas or people / real, imagined / known, or unknown

Dissociative disorders

• Disruptions or breakdowns in memory, consciousness, perception, or identity.
• Symptoms of dissociative disorders; Feeling detached from oneself or one's surroundings, memory gaps, or a sense of unreality.

What you may see in people with a learning disability and / or autistic people on dissociative disorders

• Isolation / withdrawal
• Forgetting known and familiar routines / people / places – appearing ‘lost’ and ‘confused’
• Increased / decreased appetite
• Periods of sadness / crying
• Disturbed sleep / nightmares
• Avoidance of bed / bedroom / sleep reduced / increased emotional response based on baseline presentation
• Intense mood swings
• Confusion
• Irritability – angry outbursts
• Displaying fear behaviours – fight or flight / hiding / cowering / covering head and face.

• Care and support of people growing older with learning disabilities (NICE, 2018)
• Preventing diagnostic overshadowing and identifying medical comorbidities in ASD (Thinking Autism)
• Clinical guide for front line staff to support the management of patients with a learning disability and autistic people – relevant to all clinical specialties (NHS England)
• Trauma diagnoses during emergency psychiatric evaluation among youth with and without autism spectrum disorder, Alexandra Junewicz, Sakshi Dhir, Fei Guo, Yuxiao Song, Cheryl R. Stein, Argelinda Baroni, 2024
• Diagnostic overshadowing in high-functioning Autism: Mirtazapine, Buspirone, and Modified Cognitive Behavioural Therapy (CBT) as treatment options, Nihit Gupta and Mayank Gupta
• Meeting the needs of autistic adults in mental health services: Guidance for integrated care boards, health organisations and wider system partners  (NHS England)
• Child and Adolescent Mental Health Services (CAMHS) have repeatedly failed Autistic children, particularly through diagnostic overshadowing, David Gray-Hammond (Emergent Divergence)
• Diagnostic overshadowing: a delayed diagnosis of autism spectrum disorder in a deaf child (National Center for Hearing Assessment and Management, Utah State University)
• Pain can express itself as self-harm and be missed because of diagnostic overshadowing in people with autism and a learning disability, according to new research (Autism Eye)
• Post-traumatic stress disorder in autistic people (National Autistic Society)