Autism and Co-existing Conditions fact sheet

Autism is defined as a neurodevelopmental rather than a mental health condition. This means that it is present from early on in life. It is not an illness but rather a difference in the way that information is processed by the brain. The way in which autism presents may vary between people and may also change over time. However, it is regarded as a lifelong condition.

Autism spectrum condition affects the way in which people relate to one another and process sensory information. Autistic people tend to engage in repetitive behaviours and may be restricted in their interests. If there is a good fit between the autistic person and their preferred environment and they have a supportive social network, advantages of the condition may be more prominent than disadvantages. However, for most autistic people there are challenges that need to be navigated, particularly in the early years when school attendance is required.

Autism spectrum condition can be present in people with any level of intellectual ability, and it can co-occur with other neurodevelopmental conditions, such as attention deficit hyperactivity disorder or developmental co-ordination disorder.

Autistic children are at increased risk for a co-occurring mental health condition. For example, a study by Van Steensel et al. in 2011 found that 40 percent of autistic children had at least one form of anxiety disorder.  17 percent had social anxiety and 15 percent had generalised anxiety. Research indicates that depression is four times more likely to occur in autistic than non-autistic children. Whilst rare, eating disorders are also more common in autistic children. Approximately 20 percent of children with anorexia nervosa also have autism.

There are many theories as to why autistic children are at increased risk for poor mental health. For example, autistic children may be intolerant of uncertainty and find transitions and changes in lifestyle harder to navigate. A difficulty in recognising internal emotions might increase the child’s vulnerability to stress.  Some children find the sensory and social aspects of school overwhelming and misunderstandings with other children may also contribute to social isolation, low self-esteem and bullying.

Being acutely sensitive to food taste, smell and texture or not being able to register thirst or hunger may also increase the risk of an eating disorder. A need to assert control in one area e.g dietary intake, to compensate for lack of control in another, could have negative consequences.

Fortunately, it is no longer assumed that mental health difficulties should just be accepted as an unavoidable side effect of autism. Any mental health issues should be viewed as treatable. Furthermore, for maximum efficacy, psychological support should be tailored to the social communication and learning strengths of the autistic child.

At times it can be hard to identify mental health issues as similar features may have always been present throughout the child’s life. For example, repetitive behaviours and intense, restricted interests are a key diagnostic feature of autism. At what point would these behaviours meet the threshold for a separate diagnosis of obsessive-compulsive disorder? If a child has restricted their food intake from their early years, would it be viewed as anorexia nervosa or simply reflect the avoidant and restricted food intake often seen in autism?

When in doubt a referral to Child and Adolescent Mental Health Services should be made. Professionals who are experienced in both mental health and neurodevelopment would be best placed to make that decision and to provide support accordingly.

Dr Lisa Honeyman, Clinical Psychologist

Dr Celia McElwee, Consultant Child and Adolescent Psychiatrist

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