Autism

oPatientPlus articles are written by UK doctors and are based on research evidence, UK and European Guidelines. They are designed for health professionals to use, so you may find the language more technical than the condition leaflets.

Synonym: autistic spectrum disorder (ASD)

Autism is characterised by a 'triad of impairments' in social interaction, imaginative thought and communication.[1]

There is a spectrum of disability from severely affected individuals, who produce no meaningful verbal or non-verbal communication, to high-functioning individuals, who are articulate but socially awkward and viewed as "eccentric" at the other extreme. The overarching term used by the International Statistical Classification of Diseases and Related Health Problems (ICD-10) and the Diagnostic and Statistical Manual of Mental Disorders Fourth Edition (DSM-IV) is pervasive developmental disorder. The diagnoses of autism and Asperger's syndrome fall within this spectrum.

The Autism Act was passed in 2009 and the Department of Health has followed this with "Fulfilling and rewarding lives: the strategy for adults with autism in England", which has fundamental strategies for increasing awareness in the public and diagnosis within professionals.[2]

The National Institute for Health and Clinical Excellence (NICE) has also published guidance on recognising and diagnosing autism in children and young people.[3]

Autism is a complex disorder with an established genetic basis.

  • Chromosome 7q is particularly important, although others are also thought to be involved.[4]
  • There is 88% concordance in identical twins. Siblings are more likely to be diagnosed.[5] Twins may be differently affected within the spectrum of disability.
  • Environmental factors have been implicated, although there is little conclusive evidence:
    • Toxins like lead, antimony and mercury have been found in high levels in the hair and blood samples of affected children. It may be that ASD children are unable to detoxify as efficiently as other children.
    • This hypothesis is similar to the premise behind the gluten- and casein-free diet. Peptides produced by gluten and casein act as morphine-like substances to ASD children and exaggerate their behaviours. Currently, however, there is insufficient evidence for improved behaviour with the exclusion diet.[6]
  • Measles, mumps and rubella (MMR) vaccine and autism:
    • This has been heavily covered in the media.[7][8] The position of the Medical Research Council is that, "there are no epidemiological studies that provide reliable evidence to support the hypothesis that there might be an association between MMR and ASD".[9] The majority of the original researchers who claimed a link have retracted their interpretations.[10] Wakefield has been widely discredited.[11]
    • In the USA, several claims for vaccine injury are currently progressing through the courts.[12]

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  • Prevalence is rising. In 1979 the National Autistic Society (NAS) estimated that there were 39 cases per 10,000.
  • Current incidence figures are approximately 1%.[13]
  • It is thought that the rise is due to a combination of increased and earlier, more specific diagnosis with possibly environmental factors added on. This is also supported by similar autism prevalence rates in adults (compared to children now being diagnosed) when non-selected communities are sampled and examined.[14]
  • Consistent male:female ratio 4:1

50% of parents (and more) have cause for concern by 12-18 months of age.[5] Speech delay is a common first concern. Other common concerns include:

  • Lack of, or inconsistent use of eye contact.
  • Lack of social smile, imitation, response to name.
  • Lack of interest in others.
  • Lack of emotional expression.
  • Few directed vocalisations.
  • Absence of joint attention skills (pointing to "show," following a point, monitoring others' gaze, and referencing objects or events).
  • Few requesting behaviours.
  • Few social gestures (such as waving, clapping, nodding, and shaking head).
  • Pretend play is also reduced in many children.

Regression (losing skills that have been acquired) is seen in approximately 25% of children. The skills may be in language, play or social skills.

  • 25-30% of children on the autistic spectrum may have seizures. This usually appears in puberty.[15][16] These are more common in children who have significant cognitive problems or dysmorphic features.
  • Visual impairment.
  • Hearing impairment.
  • Approximately 70% also meet diagnostic criteria for at least one other (often unrecognised) psychiatric disorder, such as depression or attention deficit hyperactivity disorder (ADHD).[17][18] This may also be impairing their social functioning.
  • Intellectual disability (IQ below 70) occurs in approximately 50%.
  • Underlying medical conditions, such as untreated phenylketonuria, congenital rubella, cytomegalovirus or toxoplasmosis, fragile X syndrome or tuberous sclerosis.
  • Pica (or mouthing) is also commonly seen.
  • Sleep disorders (of onset, maintenance and duration) are also common.

There is currently no policy for routine screening in the UK (unlike in the USA). These tools may help with a decision to refer for specialist assessment after a parent has raised concerns about their child. There are several screening questionnaires in use including:

  • The CHAT (= CH ecklist for A utism in T oddlers) and its modifications CHAT 23 and M-CHAT.
  • Pervasive developmental disorder screening test (PDDST).
  • Screening tool for autism in two-year-olds (STAT).
  • Social communication questionnaire (SCQ) is used in school-aged children.

All focus on assessing key characteristics, such as joint attention, social communication and play. A negative result from screening does not rule out the diagnosis. If parental concerns continue, a referral is advisable.[5]

The assessment of children and young people with developmental delay, emotional and behavioural problems, or genetic syndromes should include surveillance for ASD as part of routine practice.[19]

  • Asperger's syndrome.
  • Communication disorder.
  • Deafness.
  • Learning disability.
  • Childhood disintegrative disorders arising after 30 months of age (Heller's disease).
  • Rett's disorder.

The condition can be reliably diagnosed between 2-3 years of age. NICE has published guidance for assessment and referral of children with suspected autism:[3]

  • Specialist diagnosis is required. This is probably best done by paediatric neurologists, developmental and behavioural paediatricians, child psychiatrists or psychologists. Ideally there should be a multidisciplinary team ('the autism team'), with specific training and experience in evaluating children with autism.[3] Involvement of speech and language and occupational therapists, special educators, and social workers may provide a more detailed assessment of specific domains.
  • Other conditions need to be excluded and investigations for chromosome analysis, hearing and sight tests are usually taken prior to reaching the diagnosis. Where clinically relevant, the following should be considered for all children and young people with ASD:
    • Examination of physical status, with particular attention to neurological and dysmorphic features.
    • Karyotyping and fragile X DNA analysis.
    • Hearing examination.
    • Investigations to rule out recognised causes of ASD, eg tuberous sclerosis.
  • Assessments of children and young people for ASD cannot be rushed. It may not be possible to obtain sufficient evidence in one session and the child/young person may require observation in different settings, eg at school (especially in unstructured activity such as break-time) as well as clinic.
  • Autistic disorder is diagnosed when an individual exhibits six or more symptoms across the three core areas.
  • All children and young people with ASD should have a comprehensive assessment of their speech, language and communication skills. This will help to decide which interventions are best suited for that child.
  • Children whose language or social skills have regressed.
  • If you are concerned about possible autism on the basis of reported or observed signs and symptoms. Even if a screening tool is negative, consider referral if concerns persist.
  • If there are risk factors which make autism more likely:
    • Factors associated with birth; gestational age ≤35 weeks; birth defects associated with central nervous system malformation, eg cerebral palsy.
    • Family; a sibling with autism.
    • Parental ill health consequences; schizophrenia-like psychosis; sodium valproate use during pregnancy
    • A child's own health problems; intellectual disability; neonatal encephalopathy; chromosomal disorders, eg trisomy; genetic disorders, eg fragile X, muscular dystrophy, neurofibromatosis, tuberous sclerosis.

Management is usually undertaken in educational settings. Local support networks may be in place for educational support in mainstream school if appropriate and will feed down from paediatrician or educational psychologist. Occupational therapy, speech therapy and physiotherapy may help specific problems.

Many educational approaches are commonly used:

  • Applied behavioural analysis - Lovaas pioneered a system for teaching skills in bite-sized pieces by using motivators (specific to the child) to reward achievement.[20] It is taught intensively (40 hours per week) in a one-to-one situation. It should be started as early as possible. There are some specialised schools which use this method extensively. They tend to be independent and expensive. Tutors can be contacted to come to the home. See the PEACH website under 'Internet and further resources', below. There is some evidence in support of this approach, particularly for >30 hours per week.[21] However, the Lovaas programme should not be presented as an intervention that will lead to normal functioning.[19]
  • Early start Denver model - this combines applied behavioural analysis with developmental and relationship based approaches. It is aimed at toddlers and uses a developmental curriculum. The principles include bringing the child into interactive social relationships, using positive emotional exchanges, and developing joint play activities to target deficits.[5] It has been shown to improve cognitive performance, language skills and adaptive behaviour skills in some young children with autism. Unfortunately, the research methods are not robust.
  • TEACCH method (= T reatment and E ducation of A utistic and C ommunication related handicapped CH ildren) - this approach emphasises the organisation of the child's physical learning environment. Teachers use predictable sequences of activities. The child is reassured by visual schedules and visually structured activities. There is flexibility built into routines.

Other supportive interventions include:

  • Interventions supporting communication, such as the use of visual augmentation, eg pictures of objects. The picture exchange communication system (PECS) is a system of easily recognisable pictures which the child uses to communicate. This may help to reduce frustration and anxiety.
  • Speech and language therapy; this is most effective when they train and work with teachers, families and peers promoting functional communication in normal environments.
  • Social skills (in joint attention, interactive play, responding to social overtures, and initiating and maintaining social behaviour) can be taught explicitly. When children are school-aged, social skills groups can be useful. Using videos and social stories can help to teach specific skills.
  • Occupational therapy focuses on development and maintenance of fine motor and adaptive skills. It can also look at problems of processing and integrating sensory input.

No matter which approach is used, it is recommended that the intervention should be systematically planned and delivered for at least 25 hours a week, consistently.[5] It is also recommended that classrooms should have a high degree of structure and a low student-to-teacher ratio. The child's developmental level should dictate their curriculum.

Behavioural management for parents

Advise parents to join a self-help group. The NAS or parent-school partnerships often run local groups. The NAS run 'Early Bird' courses for parents. This a 12-week programme to help parents try to understand their child's behaviour and begin to cope. Contact: Early Bird Centre 01226 779218 or via email.

The behaviours that the children display can be upsetting, and misunderstood by the general public, who may stare at a "naughty child". Insight into why the child is doing these things can be helpful in helping to moderate behaviour and manage it:

  • It may be useful to try to think of the child's senses as underactive or overactive:
    • For example, if the child is under-sensitive in respect of sight, he or she may seek visual stimulation by flicking lights on and off, lining things up and holding them at the corners of his or her eyes.
    • If the child is over-sensitive, he or she may prefer the dark, blink a lot and avoid being in the sun.
    • In respect of touch, if over-sensitive, the child may find the touch of clothes (or their labels) intolerable and constantly undress. He or she may dislike hair cutting and washing and may avoid certain foods.
    • If under-sensitive, the child may bump into people for stimulation, (or have poor proprioception), want long crushing hugs, grind teeth and rarely cry when hurt.
  • Poor communication can lead to intense frustration and tantrums. Anxiety (which also leads to tantrums) can be managed with use of visual timetabling.
  • A particular problem can be fluorescent lighting, which some sufferers are able to see flickering quite clearly. This can cause bad behaviour because of sensory overload.

Complementary therapies

There are many strategies available to help parents. All claim good success, although the efficacy is not well-established for any. The major ones will be outlined and there are links if further information is required. Very few are available on the NHS and costs are generally borne by the parents:

  • Sensory integration therapy has been used when there are marked sensory perception issues, eg over-sensitivity to touch. Occupational therapists desensitise the child gently over time. Auditory Integration Therapy (AIT) is offered to children on the autistic spectrum because they appear to experience pain when listening to certain sounds. In AIT the child listens to modulated music tapes through headphones for a certain period of time. However, 50% of the studies show no benefit.[22] Therefore AIT is not recommended.
  • Evidence from trials is lacking for a gluten-/casein-free diet, although many parents claim excellent results. Luke Jackson wrote an excellent "user's guide" whilst he was a teenager.[23]

Pharmacological management

The following have been used by specialists. They are adjuncts to management plans to help with behaviours associated with ASD:[19][24]

  • Risperidone is useful for short-term treatment of significant aggression, tantrums or self-injury in children with autism. There is some evidence of benefits in irritability, repetition and social withdrawal.[25]
  • Methylphenidate may be considered for treatment of attention difficulties/hyperactivity in children or young people with ASD, although it tends to be less well tolerated.[18]
  • Melatonin may be considered for treatment of sleep problems which have persisted despite behavioural interventions. Meta-analysis has showed significant improvement with minimal side-effects.[26]
  • Some children may improve at 4-6 years of age when they may be able to model normal behaviour from school peers. There is currently a policy of inclusion within the education system which will attempt to support the majority of autistic spectrum disorder (ASD) sufferers within mainstream schools.
  • Articulate people with ASD are writing about their experiences (Temple Grandin,[27] Donna Williams[28]), and the public is more knowledgeable and sometimes sympathetic. Adults are living full lives; however, the NAS published a report in 2001 called "Ignored or ineligible? The reality for adults living with Autistic Spectrum Disorders".[29] The results were not positive and showed 49% of adults still living with parents. 12% at the higher-functioning end were in full-time employment.
  • Some will need external support and this can be accessed through a community care assessment.
  • The NAS publish good practice guidelines for services dealing with adults with ASD.[30][31]
  • "Prospects" is an NAS-supported employment service.[32]

The term autism was first used by psychiatrist Eugen Bleuler in 1911, to describe a schizophrenic patient who had withdrawn into his own world. Hans Asperger and Leo Kanner both used the term in the 1940s, working separately. Asperger described very able children. Kanner described children who were severely affected. His description, and the downbeat prognosis, persisted for the next 30 years.

Further reading & references

  1. Wing L; The spectrum of autistic disorders. Hosp Med. 2004 Sep;65(9):542-5.
  2. Fulfilling and rewarding lives: the strategy for adults with autism in England, Dept of Health, March 2010
  3. Autism spectrum disorders in children and young people, NICE Clinical Guideline (September 2011)
  4. Bonora E, Lamb JA, Barnby G, et al; Mutation screening and association analysis of six candidate genes for autism on chromosome 7q. Eur J Hum Genet. 2005 Feb;13(2):198-207.
  5. Blenner S, Reddy A, Augustyn M; Diagnosis and management of autism in childhood. BMJ. 2011 Oct 21;343:d6238. doi: 10.1136/bmj.d6238.
  6. Millward C, Ferriter M, Calver S, et al; Gluten- and casein-free diets for autistic spectrum disorder. Cochrane Database Syst Rev. 2008 Apr 16;(2):CD003498.
  7. Doja A, Roberts W; Immunizations and autism: a review of the literature. Can J Neurol Sci. 2006 Nov;33(4):341-6.
  8. Fitzpatrick M; The end of the road for the campaign against MMR. Br J Gen Pract. 2007 Aug;57(541):679.
  9. Review of Autism and Research: Epidemiology and Causes, London Medical Research Council (MRC), December 2001; review of the MMR debate
  10. Murch SH, Anthony A, Casson DH, et al; Retraction of an interpretation. Lancet. 2004 Mar 6;363(9411):750.
  11. Dyer C; Wakefield was dishonest and irresponsible over MMR research, says GMC. BMJ. 2010 Jan 29;340:c593. doi: 10.1136/bmj.c593.
  12. Stewart AM; When vaccine injury claims go to court. N Engl J Med. 2009 Jun 11;360(24):2498-500.
  13. No authors listed; Prevalence of autism spectrum disorders - Autism and Developmental Disabilities MMWR Surveill Summ. 2009 Dec 18;58(10):1-20.
  14. Brugha TS, McManus S, Bankart J, et al; Epidemiology of autism spectrum disorders in adults in the community in England. Arch Gen Psychiatry. 2011 May;68(5):459-65.
  15. Pickett J, Xiu E, Tuchman R, et al; Mortality in Individuals With Autism, With and Without Epilepsy. J Child Neurol. 2011 Apr 6.
  16. Tuchman R, Cuccaro M, Alessandri M; Autism and epilepsy: historical perspective. Brain Dev. 2010 Oct;32(9):709-18. Epub 2010 May 26.
  17. Lugnegard T, Hallerback MU, Gillberg C; Psychiatric comorbidity in young adults with a clinical diagnosis of Asperger Res Dev Disabil. 2011 Apr 23.
  18. Murray MJ; Attention-deficit/Hyperactivity Disorder in the context of Autism spectrum Curr Psychiatry Rep. 2010 Oct;12(5):382-8.
  19. Assessment, diagnosis and clinical interventions for children and young people with autism spectrum disorders; Scottish Intercollegiate Guidelines Network - SIGN (2007)
  20. Lovaas OI; Behavioral treatment and normal educational and intellectual functioning in young autistic children. J Consult Clin Psychol. 1987 Feb;55(1):3-9.
  21. Virues-Ortega J; Applied behavior analytic intervention for autism in early childhood: Clin Psychol Rev. 2010 Jun;30(4):387-99. Epub 2010 Feb 11.
  22. Sinha Y, Silove N, Wheeler D, et al; Auditory integration training and other sound therapies for autism spectrum Arch Dis Child. 2006 Dec;91(12):1018-22. Epub 2006 Aug 3.
  23. The Gluten Free/Casein Free Diet: a User's guide by Luke Jackson. London. Jessica Kingsley Publishers. ISBN 1-84310-055-x
  24. Hazell P; Drug therapy for attention-deficit/hyperactivity disorder-like symptoms in autistic disorder. J Paediatr Child Health. 2007 Jan;43(1-2):19-24.
  25. Jesner OS, Aref, Coren E; Risperidone for autism spectrum disorder. Cochrane Database Syst Rev. 2007 Jan 24;(1):CD005040.
  26. Rossignol DA, Frye RE; Melatonin in autism spectrum disorders: a systematic review and meta-analysis. Dev Med Child Neurol. 2011 Apr 19. doi: 10.1111/j.1469-8749.2011.03980.x.
  27. Thinking In Pictures and Other Reports from My Life with Autism by Temple Grandin. New York. Bantam Doubleday Dell Publishing
  28. Autism: An Inside-out Approach by Donna Williams. London. Jessica Kingsley Publishers. First hand account of what it's like to live with ASD
  29. Ignored or ineligible? The reality for adults with autism spectrum disorders, The National Autistic Society, 2001
  30. Supporting adults with autism: a good practice guide for NHS and local authorities, The National Autistic Society, 2009
  31. Good practice in supporting adults with autism, The National Autistic Society, 2009
  32. Prospects, The National Autistic Society

Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. EMIS has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.

Original Author:
Dr Hayley Willacy
Current Version:
Peer Reviewer:
Dr Helen Huins
Last Checked:
17/11/2011
Document ID:
1833 (v23)
© EMIS