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Autism spectrum

Autism, formally called autism spectrum disorder (ASD) or autism spectrum condition (ASC),[6] is a neurodevelopmental disorder marked by deficits in reciprocal social communication and the presence of restricted and repetitive patterns of behavior. Other common signs include difficulties with social interaction, verbal and nonverbal communication, along with perseverative interests, stereotypic body movements, rigid routines, and hyper- or hyporeactivity to sensory input. Autism is clinically regarded as a spectrum disorder, meaning that it can manifest very differently in each person. For example, some are nonspeaking, while others have proficient spoken language. Because of this, there is wide variation in the support needs of people across the autism spectrum.

Autism spectrum disorder

Difficulties in social interaction, verbal and nonverbal communication, and the presence of repetitive behavior or restricted interests

Early childhood

Lifelong

Multifactorial, with many uncertain factors

Family history, certain genetic conditions, having older parents, certain prescribed drugs, perinatal and neonatal health issues

Based on combination of clinical observation of behavior and development and comprehensive diagnostic testing completed by a team of qualified professionals (including psychiatrists, clinical psychologists, neuropsychologists, pediatricians, and speech-language pathologists). For adults, the use of a patient's written and oral history of autistic traits becomes more important

  • One in 100 people (1%) worldwide[5]

Psychiatry has traditionally classified autism as a mental disorder, but the autism rights movement (and an increasing number of researchers) see autistic people with low support needs as a part of humanity's natural neurodiversity.[7] From this point of view, autistic people may also be diagnosed with a disability of some sort, but that disability may be rooted in the systemic structures of a society rather than in the person;[8] thus, proponents argue that autistic people should be accommodated rather than cured.[9] The neurodiversity perspective has led to significant controversy among those who are autistic and advocates, practitioners, and charities.[10][11]


There are many theories about the causes of autism; it is highly heritable and mainly genetic, but many genes are involved, and environmental factors may also be relevant.[12] The syndrome frequently co-occurs with other conditions, including attention deficit hyperactivity disorder, epilepsy, and intellectual disability. Disagreements persist about what should be included as part of the diagnosis, whether there are meaningful subtypes or stages of autism,[13] and the significance of autism-associated traits in the wider population.[14][15] The combination of broader criteria, increased awareness, and the potential increase of actual prevalence, has led to a trend of steadily increasing estimates of autism prevalence,[16] unintentionally aiding the disproven myth perpetuated by anti-vaccine activists that it is caused by vaccines.[17]


There is no cure for autism. Although early intervention services based on applied behavior analysis (ABA) can help children gain self-care, social, and language skills,[18][19][20][21] independent living is unlikely in more severe cases. Speech and occupational therapy, as well as augmentative and alternative modes of communication, are effective adjunctive therapies, but some in the autism rights movement consider ABA therapy unethical and unhelpful.[22] Pharmacological treatments may also be useful; the atypical antipsychotics risperidone and aripiprazole are empirically validated for alleviating co-morbid irritability, though these drugs tend to be associated with sedation and weight gain.[23]

Classification

Spectrum model

Before the DSM-5 (2013) and ICD-11 (2022) diagnostic manuals were adopted, what is now called ASD was found under the diagnostic category pervasive developmental disorder. The previous system relied on a set of closely related and overlapping diagnoses such as Asperger syndrome and the syndrome formerly known as Kanner syndrome. This created unclear boundaries between the terms, so for the DSM-5 and ICD-11, a spectrum approach was taken. The new system is also more restrictive, meaning fewer people now qualify for diagnosis.[24]


The DSM-5 and ICD-11 use different categorization tools to define this spectrum. DSM-5 uses a "level" system, which ranks how in need of support the patient is,[25] while the ICD-11 system has two axes, intellectual impairment and language impairment,[26] as these are seen as the most crucial factors.


Autism is currently defined as a highly variable neurodevelopmental disorder[27] that is generally thought to cover a broad and deep spectrum, manifesting very differently from one person to another. Some have high support needs, may be non-speaking, and experience developmental delays; this is more likely with other co-existing diagnoses. Others have relatively low support needs; they may have more typical speech-language and intellectual skills but atypical social/conversation skills, narrowly focused interests, and wordy, pedantic communication.[28] They may still require significant support in some areas of their lives. The spectrum model should not be understood as a continuum running from mild to severe, but instead means that autism can present very differently in each person.[29] How it presents in a person can depend on context, and may vary over time.[30]


While the DSM and ICD greatly influence each other, there are also differences. For example, Rett syndrome was included in ASD in the DSM-5, but in the ICD-11 it was excluded and placed in the chapter on Developmental Anomalies. The ICD and the DSM change over time, and there has been collaborative work toward a convergence of the two since 1980 (when DSM-III was published and ICD-9 was current), including more rigorous biological assessment—in place of historical experience—and a simplification of the classification system.[31][32][33][34]


As of 2023, empirical and theoretical research is leading to a growing consensus among researchers that the established ASD criteria are ineffective descriptors of autism as a unitary biological entity, and that alternative research approaches must be encouraged, such as going back to autism prototypes, exploring new causal models of autism, or developing transdiagnostic endophenotypes.[35] Proposed alternatives to the current disorder-focused spectrum model deconstruct autism into at least two separate phenomena: (1) a non-pathological spectrum of behavioral traits in the population,[36][37] and (2) the neuropathological burden of rare genetic mutations and environmental risk factors potentially leading to neurodevelopmental and psychological disorders,[36][37] (3) governed by an individual's cognitive ability to compensate.[36]

ICD

The World Health Organization's International Classification of Diseases (11th Revision), ICD-11, was released in June 2018 and came into full effect as of January 2022.[38][31] It describes ASD as follows:[39]

Common characteristics

Pre-diagnosis

For many autistic people, characteristics first appear during infancy or childhood and follow a steady course without remission (different developmental timelines are described in more detail below).[46] Autistic people may be severely impaired in some respects but average, or even superior, in others.[47][48][49]


Clinicians consider assessment for ASD when a patient shows:

The most common medical condition occurring in autistic people is seizure disorder or , which occurs in 11–39% of autistic people.[214] The risk varies with age, cognitive level, and type of language disorder.[215]

epilepsy

an autosomal dominant genetic condition in which non-malignant tumors grow in the brain and on other vital organs, is present in 1–4% of autistic people.[216]

Tuberous sclerosis

are some of the most common comorbid disorders with ASDs. As diagnosis is increasingly being given to people with higher functioning autism, there is a tendency for the proportion with comorbid intellectual disability to decrease over time. In a 2019 study, it was estimated that approximately 30–40% of people diagnosed with ASD also have intellectual disability.[217] Recent research has suggested that autistic people with intellectual disability tend to have rarer, more harmful, genetic mutations than those found in people solely diagnosed with autism.[218] A number of genetic syndromes causing intellectual disability may also be comorbid with ASD, including fragile X, Down, Prader-Willi, Angelman, Williams syndrome,[219] branched-chain keto acid dehydrogenase kinase deficiency,[220][221] and SYNGAP1-related intellectual disability.[222][223]

Intellectual disabilities

are also highly comorbid in people with an ASD. Approximately 25–75% of people with an ASD also have some degree of a learning disability.[224]

Learning disabilities

Various tend to co-occur with ASDs, with overall comorbidity rates of 7–84%.[225] They are common among children with ASD; there are no firm data, but studies have reported prevalences ranging from 11% to 84%. Many anxiety disorders have symptoms that are better explained by ASD itself, or are hard to distinguish from ASD's symptoms.[226]

anxiety disorders

Rates of comorbid in people with an ASD range from 4–58%.[227]

depression

The relationship between ASD and remains a controversial subject under continued investigation, and recent meta-analyses have examined genetic, environmental, infectious, and immune risk factors that may be shared between the two conditions.[228][229][230] Oxidative stress, DNA damage and DNA repair have been postulated to play a role in the aetiopathology of both ASD and schizophrenia.[231]

schizophrenia

Deficits in ASD are often linked to behavior problems, such as difficulties following directions, being cooperative, and doing things on other people's terms. Symptoms similar to those of attention deficit hyperactivity disorder (ADHD) can be part of an ASD diagnosis.[233]

[232]

is also comorbid with ASD, with comorbidity rates of 42–88%.[234]

Sensory processing disorder

Starting in adolescence, some people with Asperger syndrome (26% in one sample) fall under the criteria for the similar condition schizoid personality disorder, which is characterized by a lack of interest in social relationships, a tendency towards a solitary or sheltered lifestyle, secretiveness, emotional coldness, detachment and apathy.[235][236][237] Asperger syndrome was traditionally called "schizoid disorder of childhood".

[235]

– about 10–15% of autism cases have an identifiable Mendelian (single-gene) condition, chromosome abnormality, or other genetic syndromes.[238]

Genetic disorders

Several , such as phenylketonuria, are associated with autistic symptoms.[239]

metabolic defects

are one of the most commonly co-occurring medical conditions in autistic people.[240] These are linked to greater social impairment, irritability, language impairments, mood changes, and behavior and sleep problems.[240][241][242] A 2015 review proposed that immune, gastrointestinal inflammation, malfunction of the autonomic nervous system, gut flora alterations, and food metabolites may cause brain neuroinflammation and dysfunction.[241] A 2016 review concludes that enteric nervous system abnormalities might play a role in neurological disorders such as autism. Neural connections and the immune system are a pathway that may allow diseases originated in the intestine to spread to the brain.[242]

Gastrointestinal problems

Sleep problems affect about two-thirds of autistic people at some point in childhood. These most commonly include symptoms of , such as difficulty falling asleep, frequent nocturnal awakenings, and early morning awakenings. Sleep problems are associated with difficult behaviors and family stress, and are often a focus of clinical attention over and above the primary ASD diagnosis.[243]

insomnia

is common in ASD, affecting heart rate and blood pressure and causing symptoms such as brain fog, blurry vision, and bowel dysfunction.[244] It can be diagnosed through a Tilt table test.[245]

Dysautonomia

The frequency of ASD is 10 times higher in patients than in the general population. This immunological condition causes cardiovascular, dermatological, gastrointestinal, neurological, and respiratory problems.[246]

Mast cell activation syndrome

Autistic pride flag

Autistic pride flag

The puzzle piece symbol as used in the autism awareness ribbon used by Autism Speaks

The puzzle piece symbol as used in the autism awareness ribbon used by Autism Speaks

An Autistic Pride flag at a "Pride is a Protest" march in June 2021

An Autistic Pride flag at a "Pride is a Protest" march in June 2021

"Neurodevelopmental Disorders". . Washington, DC: American Psychiatric Association. 18 March 2022. ISBN 978-0-89042-577-0. LCCN 2021051782.

Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision (DSM-5-TR)

. International Classification of Diseases 11th Revision (ICD-11). World Health Organisation. February 2022 [adopted in 2019]. 6A02. Retrieved 14 May 2022.

"6A02 Autism spectrum disorder"

Gabovitch, Elaine; Dutra, Courtney; Lauer, Emily. (2016). . Worcester: UMass Chan Medical School. Retrieved 30 June 2022.

The Healthy People 2020 Roadmap for Massachusetts Children & Youth with ASD/DD: Understanding Needs and Measuring Outcomes (Report)

Matson JL, Dempsey T (2008). "Stereotypy in Adults with Autism Spectrum Disorders: Relationship and Diagnostic Fidelity". . 20 (2): 155–165. doi:10.1007/s10882-007-9086-0. S2CID 143874013.

Journal of Developmental and Physical Disabilities

, Michael L Matson, Tessa T Rivet (September 2007). "Social-skills treatments for children with autism spectrum disorders: an overview". Behavior Modification. 31 (5): 682–707. doi:10.1177/0145445507301650. ISSN 0145-4455. PMID 17699124. Wikidata Q28240738.

Johnny L Matson

, Mary Shoemaker (14 July 2009). "Intellectual disability and its relationship to autism spectrum disorders". Research in Developmental Disabilities. 30 (6): 1107–1114. doi:10.1016/J.RIDD.2009.06.003. ISSN 0891-4222. PMID 19604668. Wikidata Q37552242. eISSN 1873-3379

Johnny L Matson

Pedersen AL, Pettygrove S, Lu Z, Andrews J, Meaney FJ, Kurzius-Spencer M, et al. (August 2017). "DSM Criteria that Best Differentiate Intellectual Disability from Autism Spectrum Disorder". . 48 (4): 537–545. doi:10.1007/s10578-016-0681-0. PMID 27558812. S2CID 4377173.

Child Psychiatry and Human Development

Volkmar FR, Wiesner LA (2009). . Hoboken: Wiley. ISBN 978-0-470-39473-1. OCLC 748908084. Retrieved 12 July 2022.

A practical guide to autism: what every parent, family member, and teacher needs to know

WHO fact sheet on autism