Autism is a neurodevelopmental disorder associated with deficits in social communication and/or interaction, and occurrence of restricted/repetitive patterns of behaviour, interests, or activities.
Autism was previously distinguished from Asperger’s Syndrome, but the latest version of the Diagnostic and Statistical Manual (DSM-5) instead uses a broader ‘umbrella’ category of Autism Spectrum Disorder (ASD).
The condition is associated with significant functional impairment and affects approximately 1% of the population across the globe1.
Rates of ASD are increasing by up to 15% per year, and the lifetime economic cost of providing support to an affected individual is approximately $1.4 million in the USA and £0.92 million in the UK2.
Pathology and functional impact of Autism spectrum disorder
As with most psychiatric disorders, the causes and brain basis of ASD is not fully understood. Genetic factors are important, with heritability estimates for ASD being 77-99%, higher than for many other prevalent psychiatric conditions3.
Environmental factors also play a role in the aetiology of ASD. For example, premature birth and maternal diabetes have been associated with elevated risk of offspring developing ASD4,5 though the causal pathways are unclear. Abnormalities of the cortex and cerebellum, which play key roles in cognition, are commonly reported in ASD compared to healthy controls6.
Common findings include excessive brain volumes, and other morphological abnormalities, in frontal regions and in the amygdala; coupled with lack of sufficient connectivity between brain regions6. Other research into ASD suggests that there are underlying abnormalities in antioxidant capacity and immune function, including changes to immune cells in the central nervous system7. Consistent with underlying brain changes in ASD, studies report a range of cognitive deficits in such individuals8.
Research and development in Autism spectrum disorder
The UK National Institute for Health and Care Excellence (NICE) has a number of guidelines regarding the recognition, diagnosis, and treatment of Autism9-11. Generally speaking, people with Autism should be supported via a multidisciplinary approach, by people with expertise in the disorder. This can involve support from clinical psychologists, nurses, occupational therapists, psychiatrists, social workers, speech and language therapists, and other support staff.
Other types of intervention that can be useful in some cases include leisure programmes, anger management programmes, and monitoring of vulnerability. Treatment for comorbid psychiatric conditions is important, along with providing support for families, partners, and carers.
Antipsychotic medication under specialist supervision, used alongside psychosocial intervention, is sometimes used to help manage challenging behaviour in people with Autism. However, evidence-based pharmacological interventions for the core symptoms of ASD are in high need.
The search is on for treatments that can ameliorate the core symptoms of ASD, and cognitive impairment, in order to maximise long-term outcomes and quality of life for affected individuals.
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Kenworthy L., et al (2008). Understanding executive control in autism spectrum disorders in the lab and in the real world. Neuropsychol Rev.
Buescher A.V., (2014). Costs of autism spectrum disorders in the United Kingdom and the United States. JAMA Pediatr.
Parellada M., (2014). The neurobiology of autism spectrum disorders. Eur Psychiatry.
Matsuura N.,et al (2014). Distinguishing between autism spectrum disorder and attention deficit hyperactivity disorder by using behavioral checklists, cognitive assessments, and neuropsychological test battery. Asian J Psychiatr.
Ozonoff S., et al (2004). Performance on Cambridge Neuropsychological Test Automated Battery subtests sensitive to frontal lobe function in people with autistic disorder: evidence from the Collaborative Programs of Excellence in Autism network. J Autism Dev Disord.
- Centers for Disease Control and Prevention. Data & Statistics on Autism Spectrum Disorder, 2015.
- Buescher AV, Cidav Z, Knapp M, Mandell DS. Costs of autism spectrum disorders in the United Kingdom and the United States. JAMA Pediatr. 2014 Aug;168(8):721-8.
- Colvert E, Tick B, McEwen F, Stewart C, Curran SR, Woodhouse E, Gillan N, Hallett V, Lietz S, Garnett T, Ronald A, Plomin R, Rijsdijk F, Happé F, Bolton P. Heritability of Autism Spectrum Disorder in a UK Population-Based Twin Sample. JAMA Psychiatry. 2015 May;72(5):415-23.
- Pyhälä R, Hovi P, Lahti M, Sammallahti S, Lahti J, Heinonen K, Pesonen AK, Strang-Karlsson S, Eriksson JG, Andersson S, Järvenpää AL, Kajantie E, Räikkönen K. Very low birth weight, infant growth, and autism-spectrum traits in adulthood. Pediatrics. 2014 Dec;134(6):1075-83.
- Xu G, Jing J, Bowers K, Liu B, Bao W. Maternal diabetes and the risk of autism spectrum disorders in the offspring: a systematic review and meta-analysis. J Autism Dev Disord. 2014 Apr;44(4):766-75.
- Parellada M, Penzol MJ, Pina L, Moreno C, González-Vioque E, Zalsman G, Arango C. The neurobiology of autism spectrum disorders. Eur Psychiatry. 2014 Jan;29(1):11-9.
- Mead J, Ashwood P. Evidence supporting an altered immune response in ASD. Immunol Lett. 2015 Jan;163(1):49-55.
- Kenworthy L, Yerys BE, Anthony LG, Wallace GL. Understanding executive control in autism spectrum disorders in the lab and in the real world. Neuropsychol Rev. 2008 Dec;18(4):320-38.
- NICE guidelines [CG128]. Autism diagnosis in children and young people: Recognition, referral and diagnosis of children and young people on the autism spectrum. Published date: September 2011.
- NICE quality standard [QS51]. Autism. Published date: January 2014.
- NICE guidelines [CG142] Autism: recognition, referral, diagnosis and management of adults on the autism spectrum. Published date: June 2012.