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-{{INLINETOC}} 
 ====== Autism Spectrum Disorder (ASD) ====== ====== Autism Spectrum Disorder (ASD) ======
 +{{INLINETOC}}
 ===== Primer ===== ===== Primer =====
 +<WRAP group>
 +<WRAP half column>
 **Autism Spectrum Disorder (ASD)** is a neurodevelopmental disorder characterized by: (1) persistent impairments in reciprocal social communication and social interaction,​ and (2) restricted, repetitive patterns of behaviour, interests, or activities. The manifestations and functional impact of the disorder vary greatly depending on the severity of the autistic symptoms, developmental level, and chronological age. Thus, the term //​spectrum//​ is used in the diagnosis. **Autism Spectrum Disorder (ASD)** is a neurodevelopmental disorder characterized by: (1) persistent impairments in reciprocal social communication and social interaction,​ and (2) restricted, repetitive patterns of behaviour, interests, or activities. The manifestations and functional impact of the disorder vary greatly depending on the severity of the autistic symptoms, developmental level, and chronological age. Thus, the term //​spectrum//​ is used in the diagnosis.
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 == Epidemiology == == Epidemiology ==
-The approximate prevalence of autism spectrum disorder (ASD) is 1% in both US and non-US populations. Autism spectrum disorder is diagnosed four times more often in males than in females. The prevalence of autism spectrum disorder has increased in the past few decades, rising up to prevalence rates of 1.7% (or 1 in 59 children). Reasons for this increase include expanded diagnostic criteria[([[https://​www.ncbi.nlm.nih.gov/​pubmed/​29377119/​|Arvidsson,​ O., Gillberg, C., Lichtenstein,​ P., & Lundström, S. (2018). Secular changes in the symptom level of clinically diagnosed autism. Journal of Child Psychology and Psychiatry.]])] and increased awareness. Whether these increases are due to social/​cultural changes or reflects a true increase in the actual prevalence remains unclear. Autism ​is a highly heritable conditionTwin studies show an 80% chance ​of heritabilitywhile the rate for fraternal twins is about 40%.[([[https://​www.ncbi.nlm.nih.gov/​pubmed/17003666|RonaldA., HappeF., PriceTS., Baron-CohenS., & PlominR. (2006). Phenotypic ​and genetic overlap between autistic traits at the extremes ​of the general populationJournal ​of the American ​Academy ​of Child & Adolescent Psychiatry, 45(10), 1206-1214.]])]+  * The approximate prevalence of autism spectrum disorder (ASD) is 1% in both US and non-US populations. Autism spectrum disorder is diagnosed four times more often in males than in females. ​ 
 +  * The prevalence of autism spectrum disorder has increased in the past few decades, rising up to prevalence rates of 1.7% (or 1 in 59 children). Reasons for this increase include expanded diagnostic criteria[([[https://​www.ncbi.nlm.nih.gov/​pubmed/​29377119/​|Arvidsson,​ O., Gillberg, C., Lichtenstein,​ P., & Lundström, S. (2018). Secular changes in the symptom level of clinically diagnosed autism. Journal of Child Psychology and Psychiatry.]])] and increased awareness. 
 +  * Whether these increases are due to social/​cultural changes or reflects a true increase in the actual prevalence remains unclear
 + 
 +==== Changing Diagnostic Criteria and Diagnostic Inflation ==== 
 +<alert type="​info"​ icon="​fa fa-book fa-lg fa-fw">​ 
 +See also:  
 +  * **[[https://​pubmed.ncbi.nlm.nih.gov/​32355335/​|Mottron,​ L., & Bzdok, D. (2020). Autism ​spectrum heterogeneity:​ fact or artifact?Molecular psychiatry, 1-8.]]** 
 +  * **[[https://​www.nature.com/​articles/​s41380-021-01343-3|Mottron,​ L., & Bzdok, D. (2021). Diagnosing as autistic people increasingly distant from prototypes lead neither to clinical benefit nor to the advancement ​of knowledge. Molecular Psychiatry1-3.]]** 
 +</​alert>​ 
 +  * Autism was initially considered a severe mental illness, and initially thought of as mostly a childhood psychosis (“schizoid personality disorder of childhood”) 
 +  * Over the years, the [[teaching:​cognitive-bias-misdiagnosis-overdiagnosis|expanding of the diagnostic criteria]] and conceptualization of autism as a spectrum disorder has also been thought to dilute the meaning of the diagnosis.[([[https://​www.ncbi.nlm.nih.gov/​pmc/​articles/​PMC6704749/|RødgaardE. M., JensenK., VergnesJN., SoulièresI., & MottronL. (2019). Temporal changes in effect sizes of studies comparing individuals with and without autism: a meta-analysis. JAMA psychiatry, 76(11), 1124-1132.]])] 
 + 
 +== Prognosis == 
 +  * In young children with ASD, the lack of social and communication abilities may affect learning (e.g. in social interactions or settings with peers). 
 +    * The inflexibility and insistence may interfere with routine activities such as eating, bathing, and sleeping. 
 +  * In ASD, adaptive skills are typically below the individual'​s measured IQ. 
 +  * During adulthood, some individuals may have difficulties establishing independence because ​of rigidity and difficulty with novel situations. 
 +  * Many individuals with ASD (even without intellectual disability),​ may have difficulty with independent living and gainful employment.[(American ​Psychiatric Association. (2013). Diagnostic and Statistical Manual ​of Mental Disorders ​(5th ed.). ArlingtonVA.)]
  
 == Comorbidity == == Comorbidity ==
-Adolescents and adults with autism spectrum disorder are at increased risk for [[anxiety:​gad|anxiety]] and [[mood:​1-depression:​home|depression]]. Some individuals may develop catatonic-like motor behaviour (slowing and "​freezing"​ mid-action),​ but are not usually to the severity of a true catatonic episode. [[neurology:​approaches:seizures|Epilepsy]] is also more common,​[([[https://​www.ncbi.nlm.nih.gov/​pmc/​articles/​PMC5739118/​|Besag,​ F. M. (2018). Epilepsy in patients with autism: links, risks and treatment challenges. Neuropsychiatric disease and treatment, 14, 1.]])] and is further associated with greater intellectual disability and lower verbal ability.+  * Adolescents and adults with autism spectrum disorder are at increased risk for [[anxiety:​gad|anxiety]] and [[mood:​1-depression:​home|depression]]. 
 +  * Some individuals may develop catatonic-like motor behaviour (slowing and "​freezing"​ mid-action),​ but are not usually to the severity of a true catatonic episode. 
 +  * [[neurology:​approach-seizures|Epilepsy]] is also more common,​[([[https://​www.ncbi.nlm.nih.gov/​pmc/​articles/​PMC5739118/​|Besag,​ F. M. (2018). Epilepsy in patients with autism: links, risks and treatment challenges. Neuropsychiatric disease and treatment, 14, 1.]])] and is further associated with greater intellectual disability and lower verbal ability.
  
-<callout type="​question"​ title="​What Happened to Asperger'​s,​ High Fuctioning ​Autism, and Other Diagnoses?"​ icon="​true">​ +<callout type="​question"​ title="​What Happened to Asperger'​s,​ High Functioning ​Autism, and Other Diagnoses?"​ icon="​true">​ 
-Autism spectrum disorder now encompasses other disorders previously referred to as early infantile autism, childhood autism, Kanner'​s autism, high-functioning autism, atypical autism, pervasive developmental disorder not otherwise specified, childhood disintegrative disorder, and Asperger'​s disorder.</​callout>​+Autism spectrum disorder now encompasses other disorders previously referred to as early infantile autism, childhood autism, Kanner'​s autism, high-functioning autism, atypical autism, pervasive developmental disorder not otherwise specified, childhood disintegrative disorder, and Asperger'​s disorder. 
 +</​callout>​
  
 == Risk Factors == == Risk Factors ==
-Advanced parental agelow birth weightor fetal exposure to valproatemay increase ​the risk of autism spectrum disorder. Up to 15% of cases of autism spectrum disorder may be associated with a known genetic mutation (different de novo copy number variants or de novo mutations in specific genes). Risk for the majority of cases are polygenic, with possibly hundreds of genetic loci each making small contributions. +  * Autism is a highly heritable condition.  
-===== Diagnostic Criteria =====+    * Twin studies show an 80% chance of heritabilitywhile the rate for fraternal twins is about 40%.[([[https://​www.ncbi.nlm.nih.gov/​pubmed/​17003666|RonaldA.Happe, F., Price, T. S., Baron-Cohen,​ S., & Plomin, R. (2006). Phenotypic and genetic overlap between autistic traits at the extremes ​of the general populationJournal of the American Academy of Child & Adolescent Psychiatry, 45(10), 1206-1214.]])]  
 +  * Up to 15% of cases of autism spectrum disorder may be associated with a known genetic mutation (different de novo copy number variants or de novo mutations in specific genes). 
 +  * Risk for the majority of cases are polygenic, with possibly hundreds of genetic loci each making small contributions
 +  * Advanced parental age, low birth weight, or fetal exposure to valproate, may also increase the risk of autism spectrum disorder
 +===== DSM-5 Diagnostic Criteria =====
 <WRAP group> <WRAP group>
 <WRAP half column> <WRAP half column>
 == Criterion A == == Criterion A ==
 Persistent deficits in social communication and social interaction across multiple contexts, as Persistent deficits in social communication and social interaction across multiple contexts, as
-manifested by **''​all''​** of the following, currently or by history (examples are illustrative and not exhaustive, see DSM-5 text for more examples[(http://dsm.psychiatryonline.org/​doi/​book/​10.1176/appi.books.9780890425596)]):+manifested by **''​all''​** of the following, currently or by history (examples are illustrative and not exhaustive, see DSM-5 text for more examples[(American Psychiatric Association(2013)Diagnostic and Statistical Manual of Mental Disorders (5th ed.)Arlington, VA.)]):
  
   - **Deficits in social-emotional reciprocity** (e.g. - abnormal social approach and failure of normal back-and-forth conversation;​ reduced sharing of interests, emotions, or affect; failure to initiate or respond to social interactions)   - **Deficits in social-emotional reciprocity** (e.g. - abnormal social approach and failure of normal back-and-forth conversation;​ reduced sharing of interests, emotions, or affect; failure to initiate or respond to social interactions)
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 <panel icon="​fa fa-signal"​ size="​xs"​ title="​Severity Specifier">​ <panel icon="​fa fa-signal"​ size="​xs"​ title="​Severity Specifier">​
-Criterion A severity is based on the [[child:​asd#​severity-levels-for-autism-spectrum-disorder|severity level table]] below.+''​Criterion A'' ​severity is based on the [[child:​asd#​severity-levels-for-autism-spectrum-disorder|severity level table]] below.
 </​panel>​ </​panel>​
  
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 </​WRAP>​ </​WRAP>​
 </​WRAP>​ </​WRAP>​
-<WRAP group> +
-<WRAP third column>+
 == Criterion C == == Criterion C ==
 Symptoms must be present in the early developmental period (but may not become fully manifest until social demands exceed limited capacities, or may be masked by learned strategies in later life). Symptoms must be present in the early developmental period (but may not become fully manifest until social demands exceed limited capacities, or may be masked by learned strategies in later life).
-</​WRAP>​ +
-<WRAP third column>+
 == Criterion D == == Criterion D ==
-Symptoms cause clinically significant impairment in social, occupational,​ or other important areas of +Symptoms cause clinically significant impairment in social, occupational,​ or other important areas of current functioning. 
-current functioning. +
-</​WRAP>​ +
-<WRAP third column>+
 == Criterion E == == Criterion E ==
 These disturbances are not better explained by intellectual disability (intellectual developmental These disturbances are not better explained by intellectual disability (intellectual developmental
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 co-occur; to make co-morbid diagnoses of autism spectrum disorder and intellectual disability, social co-occur; to make co-morbid diagnoses of autism spectrum disorder and intellectual disability, social
 communication should be below that expected for general developmental level. communication should be below that expected for general developmental level.
-</​WRAP>​ + 
-</​WRAP>​ +<callout type="​tip"​ title="​DSM-IV to DSM-5 Changes"​ icon="​true">​ 
-<callout type="​tip"​ title="​DSM-IV to DSM-5 Changes"​ icon="​true">​ Individuals with a well-established DSM-IV diagnosis of autistic disorder, Asperger’s disorder, or pervasive developmental disorder not otherwise specified should be given the diagnosis of autism spectrum disorder. Individuals who have marked deficits in social communication,​ but whose symptoms do not otherwise meet criteria for autism spectrum disorder, should be evaluated for [[child:​communication:​home#​social-pragmatic-communication-disorder|social (pragmatic) communication disorder]].</​callout>​+Individuals with a well-established DSM-IV diagnosis of autistic disorder, Asperger’s disorder, or pervasive developmental disorder not otherwise specified should be given the diagnosis of autism spectrum disorder. Individuals who have marked deficits in social communication,​ but whose symptoms do not otherwise meet criteria for autism spectrum disorder, should be evaluated for [[child:​communication:​home#​social-pragmatic-communication-disorder|social (pragmatic) communication disorder]]. 
 +</​callout>​
  
 ==== Specifiers ==== ==== Specifiers ====
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 <WRAP half column> <WRAP half column>
 <panel icon="​fa fa-signal"​ size="​xs"​ title="​Severity Levels for Autism Spectrum Disorder"​ no-body="​true">​ <panel icon="​fa fa-signal"​ size="​xs"​ title="​Severity Levels for Autism Spectrum Disorder"​ no-body="​true">​
 +<​mobiletable 1>
 ^ Severity (Level) ​                             ^ Social Communication (Criterion A)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                ^ Restricted, Repetitive Behaviours (Criterion B)                                                                                                                                                                                                                                   ^ ^ Severity (Level) ​                             ^ Social Communication (Criterion A)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                ^ Restricted, Repetitive Behaviours (Criterion B)                                                                                                                                                                                                                                   ^
 ^ Requiring very substantial support (Level 3)  | Severe deficits in verbal and nonverbal social communication skills cause severe impairments in functioning,​ very limited initiation of social interactions,​ and minimal response to social overtures from others. For example, a person with few words of intelligible speech who rarely initiates interaction and, when he or she does, makes unusual approaches to meet needs only and responds to only very direct social approaches. ​                                                                        | Inflexibility of behaviour, extreme difficulty coping with change, or other restricted/​repetitive behaviours, markedly interfere with functioning in all spheres. Great distress/​difficulty changing focus or action. ​                                                            | ^ Requiring very substantial support (Level 3)  | Severe deficits in verbal and nonverbal social communication skills cause severe impairments in functioning,​ very limited initiation of social interactions,​ and minimal response to social overtures from others. For example, a person with few words of intelligible speech who rarely initiates interaction and, when he or she does, makes unusual approaches to meet needs only and responds to only very direct social approaches. ​                                                                        | Inflexibility of behaviour, extreme difficulty coping with change, or other restricted/​repetitive behaviours, markedly interfere with functioning in all spheres. Great distress/​difficulty changing focus or action. ​                                                            |
 ^ Requiring substantial support (Level 2)       | Marked deficits in verbal and nonverbal social communication skills; social impairments apparent even with supports in place; limited initiation of social interactions;​ and reduced or abnormal responses to social overtures from others. For example, a person who speaks simple sentences, whose interaction is limited to narrow special interests, and who has markedly odd nonverbal communication. ​                                                                                                       | Inflexibility of behaviour, difficulty coping with change, or other restricted/​repetitive behaviours appear frequently enough to be obvious to the casual observer and interfere with functioning in a variety of contexts. Distress and/or difficulty changing focus or action. ​ | ^ Requiring substantial support (Level 2)       | Marked deficits in verbal and nonverbal social communication skills; social impairments apparent even with supports in place; limited initiation of social interactions;​ and reduced or abnormal responses to social overtures from others. For example, a person who speaks simple sentences, whose interaction is limited to narrow special interests, and who has markedly odd nonverbal communication. ​                                                                                                       | Inflexibility of behaviour, difficulty coping with change, or other restricted/​repetitive behaviours appear frequently enough to be obvious to the casual observer and interfere with functioning in a variety of contexts. Distress and/or difficulty changing focus or action. ​ |
 ^ Requiring support (Level 1)                   | Without supports in place, deficits in social communication cause noticeable impairments. Difficulty initiating social interactions,​ and clear examples of atypical or unsuccessful responses to social overtures of others. May appear to have decreased interest in social interactions. For example, a person who is able to speak in full sentences and engages in communication but whose to-and-fro conversation with others fails, and whose attempts to make friends are odd and typically unsuccessful. ​ | Inflexibility of behaviour causes significant interference with functioning in one or more contexts. Difficulty switching between activities. Problems of organization and planning hamper independence. ​                                                                         | ^ Requiring support (Level 1)                   | Without supports in place, deficits in social communication cause noticeable impairments. Difficulty initiating social interactions,​ and clear examples of atypical or unsuccessful responses to social overtures of others. May appear to have decreased interest in social interactions. For example, a person who is able to speak in full sentences and engages in communication but whose to-and-fro conversation with others fails, and whose attempts to make friends are odd and typically unsuccessful. ​ | Inflexibility of behaviour causes significant interference with functioning in one or more contexts. Difficulty switching between activities. Problems of organization and planning hamper independence. ​                                                                         |
 +</​mobiletable>​
 </​panel>​ </​panel>​
 </​WRAP>​ </​WRAP>​
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 Symptoms of autism are typically recognized during the second year of life (12-24 months of age), and can be reliably diagnosed by age 14 months.[([[https://​www.ncbi.nlm.nih.gov/​pubmed/​31034004|Pierce,​ K., Gazestani, V. H., Bacon, E., Barnes, C. C., Cha, D., Nalabolu, S., ... & Courchesne, E. (2019). Evaluation of the Diagnostic Stability of the Early Autism Spectrum Disorder Phenotype in the General Population Starting at 12 Months. JAMA pediatrics.]])] Symptoms of autism are typically recognized during the second year of life (12-24 months of age), and can be reliably diagnosed by age 14 months.[([[https://​www.ncbi.nlm.nih.gov/​pubmed/​31034004|Pierce,​ K., Gazestani, V. H., Bacon, E., Barnes, C. C., Cha, D., Nalabolu, S., ... & Courchesne, E. (2019). Evaluation of the Diagnostic Stability of the Early Autism Spectrum Disorder Phenotype in the General Population Starting at 12 Months. JAMA pediatrics.]])]
  
-In the first year of life, the first symptoms of autism spectrum disorder involve delayed language development,​ often accompanied by lack of social interest or unusual social interactions. By the second year, odd and repetitive behaviors and the absence of typical play becomes more apparent. All young children have strong preferences and enjoy repetition (e.g. - eating the same foods, watching the same video multiple times), which can make distinguishing restricted and repetitive behaviors that are diagnostic of autism spectrum disorder can be difficult. This can be distinguished based on the type, frequency, and intensity of the behaviour (e.g. - a child who lines up objects for hours every day and is becomes distressed if any item is moved).+  * In the first year of life, the first symptoms of autism spectrum disorder involve delayed language development,​ often accompanied by lack of social interest or unusual social interactions. 
 +  * By the second year, odd and repetitive behaviors and the absence of typical play becomes more apparent. All young children have strong preferences and enjoy repetition (e.g. - eating the same foods, watching the same video multiple times), which can make distinguishing restricted and repetitive behaviors that are diagnostic of autism spectrum disorder can be difficult.[([[https://​www.ncbi.nlm.nih.gov/​pmc/​articles/​PMC3601920/​|Cermak,​ S. A., Curtin, C., & Bandini, L. G. (2010). Food selectivity and sensory sensitivity in children with autism spectrum disorders. Journal of the American Dietetic Association,​ 110(2), 238-246.]])] ​This can be distinguished based on the type, frequency, and intensity of the behaviour (e.g. - a child who lines up objects for hours every day and is becomes distressed if any item is moved). 
 + 
 +  * Some children with autism spectrum disorder experience developmental plateaus or regression, with a gradual or relatively rapid deterioration in social behaviours or use of language, often in the first two years of life. This is a "red flag" for autism spectrum disorder.  
 +  * If the loss of skills are beyond social communication (e.g. - loss of self-care, toileting, motor skills) or those occurring after the second year of life, then extensive medical investigations and a thorough differential diagnosis should be considered (including Rett Syndrome). 
 + 
 +  * Sleep disturbances are also extremely common in children with ASD, with the prevalence of sleep disturbances estimated to be as high as 40% to 80%.[([[https://​www.ncbi.nlm.nih.gov/​pmc/​articles/​PMC2786040/​|Souders,​ M. C., Mason, T. B., Valladares, O., Bucan, M., Levy, S. E., Mandell, D. S., ... & Pinto-Martin,​ J. (2009). Sleep behaviors and sleep quality in children with autism spectrum disorders. Sleep, 32(12), 1566-1578.]])]
  
-Some children with autism spectrum disorder experience developmental plateaus or regression, with a gradual or relatively rapid deterioration in social behaviours or use of language, often in the first two years of life. This is a "red flag" for autism spectrum disorder. If the loss of skills are beyond social communication (e.g. - loss of self-care, toileting, motor skills) or those occurring after the second year of life, then extensive medical investigations and a thorough differential diagnosis should be considered (including Rett Syndrome). 
 </​WRAP>​ </​WRAP>​
 <WRAP half column> <WRAP half column>
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   * Use of another persons'​s body as a tool is almost pathognomonic for autism (e.g. - child using parent'​s hand as a tool to achieve a task)   * Use of another persons'​s body as a tool is almost pathognomonic for autism (e.g. - child using parent'​s hand as a tool to achieve a task)
   * Seems to be in his/her "own world"   * Seems to be in his/her "own world"
 +  * Doesn'​t respond to own name when called
   * Doesn’t respond to parent’s attempts to play, even if relaxed   * Doesn’t respond to parent’s attempts to play, even if relaxed
   * Avoids or ignores other children when they approach or interact   * Avoids or ignores other children when they approach or interact
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   * Doesn’t bring a toy or other item to parent to show them   * Doesn’t bring a toy or other item to parent to show them
 </​callout>​ </​callout>​
 +
 <callout type="​success"​ title="​Factors That Rule Out Autism"​ icon="​true">​ <callout type="​success"​ title="​Factors That Rule Out Autism"​ icon="​true">​
 Evidence of good social and communication skills in childhood rules out a autism spectrum disorder. For example, if parents report the individual had ordinary and sustained reciprocal friendships and good nonverbal communication skills throughout childhood, this would rule out a diagnosis of autism spectrum disorder. Evidence of good social and communication skills in childhood rules out a autism spectrum disorder. For example, if parents report the individual had ordinary and sustained reciprocal friendships and good nonverbal communication skills throughout childhood, this would rule out a diagnosis of autism spectrum disorder.
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 </​WRAP>​ </​WRAP>​
 </​WRAP>​ </​WRAP>​
 +
  
 ===== Screening Tools and Rating Scales ===== ===== Screening Tools and Rating Scales =====
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   * Autism Spectrum Quotient (AQ) (Adult, Adolescent, and Child versions)   * Autism Spectrum Quotient (AQ) (Adult, Adolescent, and Child versions)
-  * Quantitative Checklist for Autism in Toddlers (Q-CHAT) ​+  * Quantitative Checklist for Autism in Toddlers (Q-CHAT
 +  * Modified Checklist for Autism in Toddlers, Revised (M-CHAT-R)
 ===== Pathophysiology ===== ===== Pathophysiology =====
 Less than 1 percent of non-syndromic cases of autism are due to mutations in a single gene. The environment (ranging from chemical changes in gene expression, to the absorption of nutrients in the womb) is also thought to play a factor.[([[https://​www.ncbi.nlm.nih.gov/​pubmed/​21727249|Hallmayer,​ J., Cleveland, S., Torres, A., Phillips, J., Cohen, B., Torigoe, T., ... & Lotspeich, L. (2011). Genetic heritability and shared environmental factors among twin pairs with autism. Archives of general psychiatry, 68(11), 1095-1102.]])] Less than 1 percent of non-syndromic cases of autism are due to mutations in a single gene. The environment (ranging from chemical changes in gene expression, to the absorption of nutrients in the womb) is also thought to play a factor.[([[https://​www.ncbi.nlm.nih.gov/​pubmed/​21727249|Hallmayer,​ J., Cleveland, S., Torres, A., Phillips, J., Cohen, B., Torigoe, T., ... & Lotspeich, L. (2011). Genetic heritability and shared environmental factors among twin pairs with autism. Archives of general psychiatry, 68(11), 1095-1102.]])]
  
 ===== Differential Diagnosis ===== ===== Differential Diagnosis =====
 +<alert type="​info"​ icon="​fa fa-book fa-lg fa-fw">​
 +See also: **[[https://​pubmed.ncbi.nlm.nih.gov/​34482753/​|Defresne,​ P., & Mottron, L. (2021). Clinical Situations in Which the Diagnosis of Autism is Debatable: An Analysis and Recommendations,​ The Canadian Journal of Psychiatry, 07067437211041469.]]**
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 ===== Investigations ===== ===== Investigations =====
 +  * Genome-wide microarray analysis should be ordered in all individuals diagnosed with ASD[([[https://​pubmed.ncbi.nlm.nih.gov/​24418986/​|Anagnostou,​ E., Zwaigenbaum,​ L., Szatmari, P., Fombonne, E., Fernandez, B. A., Woodbury-Smith,​ M., ... & Scherer, S. W. (2014). Autism spectrum disorder: advances in evidence-based practice. Cmaj, 186(7), 509-519.]])] 
 +  * Testing for [[child:​genetic-disorders:​fragile-x-syndrome-fxs|fragile X syndrome]] and sequencing of the PTEN gene for individuals with a large head circumference (three or more standard deviations above the mean)
 ===== Treatment ===== ===== Treatment =====
-Early, aggressive intervention has been shown to be effective in reducing symptoms.[(http://www.healthline.com/health-news/early-intervention-erases-autism-symptoms-090914#2)]+  * Early, aggressive intervention has been shown to be effective in reducing symptoms
 +  * Applied behaviour analysis (ABA) is an evidence-based treatment that uses theories of learning and operant conditioning to address core symptoms of ASD.[([[https://pubmed.ncbi.nlm.nih.gov/18775372/|Foxx, R. M. (2008). Applied behavior analysis treatment of autism: The state of the art. Child and adolescent psychiatric clinics of North America, 17(4), 821-834.]])] 
 +===== Guidelines ===== 
 +<alert icon="​fa fa-arrow-circle-right fa-lg fa-fw" type="​success">​See also: **[[teaching:​clinical-practice-guidelines-cpg|]]**</​alert>​ 
 + 
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-===== Prognosis ===== 
-In young children with autism spectrum disorder, lack of social and communication abilities may hamper learning, especially learning through social interaction or in settings with peers. In the home, insistence on routines and aversion to change, as well as sensory sensitivities,​ may interfere with eating and sleeping and make routine care (e.g. - haircuts, dental work) extremely difficult. Adaptive skills are typically below measured IQ. Extreme difficulties in planning, organization,​ and coping with change negatively impact academic achievement,​ even for students with above-average intelligence. During adulthood, these individuals may have difficulties establishing independence because of continued rigidity and difficulty with novelty. Many individuals with autism spectrum disorder, even without intellectual disability, have poor adult psychosocial functioning as indexed by measures such as independent living and gainful employment. Functional consequences in old age are unknown, but social isolation and communication problems (e.g. - reduced help-seeking) are likely to have consequences for health in older adulthood. 
 ===== Resources ===== ===== Resources =====
  
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-==== For Patients ​====+== For Patients ==
   * [[https://​medschool.ucsd.edu/​som/​neurosciences/​centers/​autism/​treating-early-autism/​Pages/​signs.aspx|UC San Diego - Early Warning Signs of Autism]]   * [[https://​medschool.ucsd.edu/​som/​neurosciences/​centers/​autism/​treating-early-autism/​Pages/​signs.aspx|UC San Diego - Early Warning Signs of Autism]]
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-==== For Providers ​==== +== For Providers == 
 +  * **[[https://​www.nature.com/​articles/​s41572-019-0138-4|Lord,​ C. et al. (2020). Autism spectrum disorder. Nature Reviews Disease Primers, 6(1), 1-23.]]**
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 == Articles == == Articles ==
   * [[http://​www.cbc.ca/​news/​health/​autism-spectrum-disorder-public-health-agency-of-canada-1.4598859|CBC:​ 1 in 66 Canadian children diagnosed with autism, report reveals]]   * [[http://​www.cbc.ca/​news/​health/​autism-spectrum-disorder-public-health-agency-of-canada-1.4598859|CBC:​ 1 in 66 Canadian children diagnosed with autism, report reveals]]
 +  * [[https://​www.theguardian.com/​commentisfree/​2019/​aug/​26/​autism-neurodiversity-severe|The Guardian: What is autism? How the term became too broad to have meaning any more]]
  
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