Autism Spectrum Disorder
Content
CHILDHOOD, ADOLESCENCE AND BEYOND
Autism spectrum disorder
Imtiazul Haq Ann Le Couteur
Aetiology
Genetic factors are important. It is likely that the phenotype results from several genes, possibly involving 2q and 7q, acting together. The British Twin Study estimated a broad heritability of 91–93% and a concordance of 69% in monozygotic twins. Psychological deficit theories have failed to identify a primary t deficit that could account for all of the features of the autistic phenotype. ‘Theory of mind’ has been implicated as a possible psychological mechanism underlying ASD.19 Biological deficit – the organic basis of ASD is well recognized, t but the biological deficits remain unclear. Physiological abnormalities of the gastrointestinal tract and immune system have been investigated as possible causal factors, but the only consistent finding is nonspecific raised blood serotonin.20
Increased awareness has placed great emphasis on the understanding of autism spectrum disorder (ASD). Some authors argue that ASD should be considered a common disorder of childhood.1,2 Autism was first described in 1943 by Kanner, and in 1944 Asperger described children with similar difficulties;3,4 at about the same time, other children with characteristics of ASD were described as having schizophrenia or infantile psychosis.5,6 In the 1960s and early 1970s, studies confirmed that children with behaviours similar to those described by Kanner could be reliably distinguished from mentally disabled children and those with other psychiatric disorders.7,8 The term ‘pervasive developmental disorder’ (PDD) was introduced by the American Psychiatric Association in 1980, and was adopted by the ICD9 and the DSM10 to cover both core autism and a broader range of autistic-like disorders. Recently, there has been a move to replace ‘PDD’ with ‘ASD’,11 reflecting the finding that there are more overlaps than differences between subcategories. ASD describes a constellation of features characterized by qualitative abnormalities in reciprocal social interactions and patterns of communication, and by restricted, stereotyped, repetitive interests and activities. These abnormalities are pervasive in all situations, but may vary in degree. It is now generally recognized that there is a spectrum of severity of the behavioural symptoms and intellectual ability, from severely impaired to high functioning. Use of the term ‘ASD’ reflects the continuity between autism and related disorders,12,13,14 and acknowledges the need to plan for assessment, diagnosis, intervention and support services for a larger number of individuals than was previously considered.
Clinical features and diagnosis
Many features of ASD appear to be consistent across cultures. A child in rural Guatemala may peer at a flag made from leaves and sticks in the same manner that a child in suburban Chicago squints at a flag made from McDonald’s swizzle sticks and sweetener packets. However, identical twins with ASD may vary in IQ by as much as 50 and lead very different lives, one driving his own car to work and the other requiring assistance with basic hygiene.21 In most cases, the parents of an affected child become concerned about abnormalities or delays in his or her second year. Often, the problems are not specific autistic features, but rather worries that the child is less talkative, or has temper tantrums or difficulties in settling, eating or sleeping. Many under-3s who will eventually meet the formal criteria for ASD do not yet show clear examples of restrictive or repetitive behaviours. Clinical diagnosis of autism requires evidence of three areas of deficit (social reciprocity, communication, and restricted, repetitive behaviours and interests) together with a report of some form of delay or deviance before 36 months of age. Not all individuals with ASD exhibit difficulties in all three areas at the same time. Communication – delay or deviance in development of language is an important feature of ASD. Language delay is usual. About 50% of individuals with a diagnosis of autism never achieve useful speech. Those who develop speech have difficulties with the social use of language, and speech abnormalities such as stereotyped phrases and pronoun reversal. Abnormalities of pitch and rhythm are more common in ASD than in general mental retardation/learning disability. ASD is also associated with deficits in non-verbal communication, including use of gestures such as pointing, nodding and showing. An affected child who wants a drink may have a tantrum or put the adult’s hand on the bottle to communicate the request, rather than using eye contact, gestures or vocalization. Deficits also occur in imitation, social play, spontaneous imaginative roleplay, and play with dolls or action figures. Shared play with other children may be impaired. Social interaction – deficits in reciprocal social interaction are a core feature of ASD.12 Infants and young children may not respond as expected to physical contact with a care-giver. Social use of smiling and other facial expressions may not develop or may appear inappropriate. Young children may not react to their carer’s voice, and it may be difficult to catch their attention.
Epidemiology
The prevalence of ASD varies between studies. According to recent reviews, however, ASD appears to affect about 60 children per 10,000 under 8 years of age, and 10–30 per 10,000 have narrowly defined autism.15,16,17,18 These estimates confirm that ASD is more common than was previously recognized. The observed increase may be at least partly a consequence of more complete ascertainment and the broader definition of ASD. Boys are 3–4 times more likely to have autism than girls, and the male preponderance is even more marked at the higher-functioning end of the spectrum.
Imtiazul Haq is Specialist Registrar in Child Psychiatry in the Fleming Nuffield Unit, Newcastle upon Tyne, UK. Ann Le Couteur is Professor of Child and Adolescent Psychiatry at the r University of Newcastle upon Tyne, UK.
MEDICINE
61
© 2004 The Medicine Publishing Company Ltd
CHILDHOOD, ADOLESCENCE AND BEYOND
With increasing age, social deficits may become more obvious. A child who lacks interest in other children can play successfully alongside them, but will experience problems as social expectations in shared play become more complex. Children with ASD often become isolated, are at risk of being bullied, and lack the social skills required to develop successful friendships. Repetitive behaviour and interests – children with ASD exhibit restricted, repetitive behaviours and interests. These may include unusual preoccupations (e.g. street signs, drainpipes), circumscribed interests (e.g. timetables, motorcycles) and attachment to unusual objects (e.g. a jar of lentils, belts, brushes). Other associated features include: • compulsions and rituals • unusual hand, finger or whole-body movements (stereotypical movements of hands and fingers are often within the peripheral vision) • repetitive use of objects • unusual interests in the sight, sound, smell or feel of objects or people. Children with ASD may also be preoccupied with sameness, and many are disturbed by changes in their routines. It is said that the form of the rituals and compulsive behaviours seen in ASD differs from that in obsessive–compulsive disorder (OCD). Many individuals with ASD are not upset by their compulsive behaviours and apparently make no effort to prevent them.
to the others.25,26 Behavioural and educational approaches have been emphasized, and involving parents as ‘co-therapists’ to foster social–communicative interactions may prevent secondary behavioural problems. There is emerging evidence that targeted interventions should begin as early as possible,27,28 to increase the likelihood that individuals with ASD will attain their full potential. The National Autism Plan for Children recommends that preschool children should have access to appropriate ASD-specific programmes for 15 hours per week. For both pre-school and school-aged children, the Family Care and Individual Education Plans ideally include clear ASD management strategies for staff and parents, and access to ASD-specific individual or small-group therapeutic educational opportunities as dictated by needs. There is no definitive evidence that pharmacological intervention alters the long-term prognosis. However, drugs combined with behavioural analysis and appropriate psycho-educational interventions may enable children with ASD to modify their behaviour in a manner that would have been impossible without their use.
Autism in adulthood
Autism is a lifelong disorder and the likelihood of complete independence is limited. Diagnosis in adulthood can be difficult and depends largely on the developmental history. Adults without mental retardation and with good verbal skills may participate in social interactions relatively well, but experience difficulties in forming relationships and coping with the social demands of the workplace. Most adults with ASD, even those with average or above-average abilities, require help in finding and keeping jobs and coping with responsibilities. Co-morbid psychiatric disorders (particularly depression and anxiety) are common, and access to psychiatric services for assessment and treatment is vital.
Associated conditions and differential diagnosis
IQ is less than 70 in 80% of individuals with narrowly defined autism, and at least one-quarter to one-third will develop epilepsy; onset of seizures peaks in early childhood and in adolescence. Co-morbid diagnoses include social anxiety and social phobias, attention deficit hyperactivity disorder, depression and OCD. Other conditions that can mimic the symptoms of ASD and should be differentiated include receptive–expressive language disorders, severe psychosocial deprivation, selective mutism, neurodevelopmental disorders (e.g. Tourette’s syndrome) and regressive disorders (e.g. tuberous sclerosis, childhood disintegrative disorder, Landau–Kleffner syndrome, Rett’s syndrome).
Asperger’s syndrome
Asperger’s syndrome is an ASD. The term is most commonly used to describe those with autism who do not have a learning difficulty. In both ICD-10 and DSM-IV, the essential criterion for diagnosis of Asperger’s syndrome is absence of delay in development of language and other adaptive skills. Individuals with Asperger’s syndrome usually have IQs in the normal range, and their verbal skill scores may be as good as or higher than non-verbal.
REFERENCES 1 Filipek P A et al. The screening and diagnosis of autistic spectrum disorders. J Autism Dev Disord 1999; 29: 439–84. d 2 Filipek P A et al. Practice parameters: screening and diagnosis of autism. Report of quality standards subcommittee of the American Academy of Neurology and the Child Neurology Society. Neurology 2000: 55: 468–79. 3 Frith U. Autism and Asperger syndrome. Cambridge: Cambridge University Press, 1991. 4 Ozonoff S, Pennington B F, Rogers S J. Executive function deficits in high-functioning autistic children: relationship theory of mind. J Child Psychol Psychiatry 1991; 32: 1081–105. y 5 Bender L. Childhood schizophrenia. Nervous Child 1942; 1: 138–40. d 6 Mahler M S. On childhood psychosis and schizophrenia: autistic and symbiotic psychosis. Psychoanal Study Child 1952; 7: 286–305. d 7 Rutter M, Greenfield D, Lockyer L. A five to fifteen year follow-up
Management
The UK National Initiative for Autism Screening and Assessment has been supported by the Royal College of Paediatrics and Child Health, the Royal College of Psychiatrists, the National Autistic Society and the All Party Parliamentary Group on Autism to produce the National Autism Plan for Children.11 The plan provides national guidelines for screening, investigation, early diagnosis and intervention in pre-school and primary school-aged children. These guidelines recommend that multi-agency assessment should be available in all areas and that, in addition to general and autismspecific developmental assessment, these should include psychometric, educational, communication, language, motor competency, behaviour and mental health assessments. Recent studies show that a valid clinical diagnosis can be made at age 2–3 years,14,22,23,24 though diagnosis is more difficult in young children who are more able and in those with significant developmental delay. Research has supported the effectiveness of various interventions, but there is no evidence that any one approach is superior
MEDICINE
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© 2004 The Medicine Publishing Company Ltd
CHILDHOOD, ADOLESCENCE AND BEYOND
study of infantile psychosis. II. Social and behavioural outcome. Br J Psychiatry 1967; 113: 1183–99. y 8 DeMyer M K, Barton S, Norton J A. A comparison of adaptive, verbal and motor profiles of psychotic and non psychotic subnormal children. J Autism Child Schizophr 1972; 2: 359–77. r 9 WHO. ICD-10: classification of mental and behavioural disorders. Geneva: WHO, 1992. 10 American Psychiatric Association. Diagnostic and statistical manual of mental disorders. 4th ed. Washington: American Psychiatric Association, 1994. 11 Le Couteur A, ed. National autism plan for children. London: National Autism Society, 2003. 12 Wing L, Gould J. Severe impairments of social interaction and associated abnormalities in children: epidemiology and classification. J Autism Dev Disord 1979; 9: 11–29. d 13 Wing L. The autistic spectrum: a guide for parents and professionals. London: Constable, 1996. 14 Lord C, Risi S, Lambrecht L et al. The Autism Diagnostic Observation Schedule – Generic: a standard measure of social and communication deficits associated with the spectrum of autism. J Autism Dev Disord 2000; 30: 205–23. d 15 Baird G, Charman T, Baron-Cohen S. A screening instrument for autism at 18 months of age: a six-year follow-up study. J Am Acad Child Adolesc Psychiatry 2000; 39: 694–702. y 16 Scott F, Baron-Cohen S, Bolton P. Brief report: prevalence of autism spectrum conditions in children aged 5 to 11 years in Cambridgeshire, UK. Autism 2002; 6: 231–7. 17 Bertrand J, Mars A, Boyle C et al. Prevalence of autism in a United States population: the Brick Township investigations. Pediatrics 2001; 108: 1155–61. 18 Chakrabarti S, Fombonne E. Pervasive developmental disorders in pre-school children. JAMA 2001; 285: 3093–9. 19 Baron-Cohen S. Autism: a specific disorder of ‘mind blindness’. Int Rev Psychiatry 1990; 2: 79–88. y 20 McBride P A, Anderson G M, Hertzig M E et al. Effects of diagnosis, race and puberty on platelet serotonin levels in autism and mental retardation. J Am Acad Child Adolesc Psychiatry 1998; 37: 767–76. y 21 Lord C, Bailey A. Autism spectrum disorders. In: Rutter M, Taylor E, eds. Child and adolescent psychiatry. 4th ed. Oxford: Blackwell, 2002: 636–63. 22 Lord C, Magill-Evans J. Peer interactions of autistic children and adolescents. Dev Psychopathol 1995; 7: 611–26. 23 Cox A, Klein K, Charman T et al. Autism spectrum disorders at 20 and 42 months of age: stability of clinical and ADI-R diagnosis. J Child Psychol Psychiatry 1999; 40: 719–32. y 24 Stone W L, Lee E B, Ashford L et al. Can autism be diagnosed accurately in children under 3 years? J Child Psychol Psychiatry 1999; y 40: 219–26. 25 Dawson G, Osterling J. Early intervention in autism: effectiveness and common elements of current approaches. In: Guralnick M, ed. Effectiveness and early intervention: second generation research. Baltimore: Brookes, 1997: 307–26. 26 Jordan R, Jones G, Murray D. Educational interventions for children with autism: a literature review of recent and current research. (Research Report 77). London: Department of Education and Employment, 1998. 27 Handleman J S, Harris S. Preschool education programs for children with autism. Austin: Pro-Ed, 2000. 28 Howlin P, Charman A. Presentation to NIASA Working Group, 2001.
Eating disorders
J Treasure
Definitions
• Anorexia nervosa is characterized by refusal to maintain weight at or above a minimally normal weight (85% of expected weight for age and height, or body mass index (BMI) 17.5 kg/m2), or failure to exhibit the expected weight gain during growth. There is often associated intense fear of gaining weight, preoccupation with weight, denial of the current low weight and its adverse impact on health, and amenorrhoea. • Bulimia nervosa shares some features with anorexia nervosa (e.g. intense preoccupation with weight and shape), but is characterized by regular episodes of uncontrolled eating (> 1000 kcal) associated with various methods of counteracting weight gain (vomiting and laxative abuse are most common). • Various subtypes of eating disorders are defined within the spectrum of eating problems (Figure 1).
Epidemiology
Anorexia nervosa has a long history and is present in diverse cultural settings. The content of the psychopathology of anorexia nervosa varies with time and place; for example, weight phobia is not always present in non-Western societies. Bulimia nervosa became more common in the second half of the 20th century and was recognized as a new syndrome in Western societies in 1979.1 The mean incidence of anorexia nervosa in females is 19/100,000/year (about tenfold more than the male incidence).2 The highest prevalence is 0.5% in female teenagers. The prevalence of bulimia nervosa is 1% in young women. Overall, 5–10% of young women have some form of eating problem.
Aetiology and risk factors
Family, biological, social and cultural factors may have a role in the development and the maintenance of eating disorders. The evidence for such risk factors is collated in two recent systematic reviews.3,4 • The risk of eating disorders in first-degree relatives of affected individuals is increased tenfold, and twin studies suggest that this is because of inherited factors. Preliminary studies suggest that a region on chromosome 1 is linked with anorexia nervosa5 and on chromosome 10 with bulimia nervosa.6
J Treasure is Director of the Eating Disorder Unit and Professor of Psychiatry at Guy’s, King’s and St Thomas’ Medical School, London, UK.
MEDICINE
63
© 2004 The Medicine Publishing Company Ltd
Autism spectrum disorder
Imtiazul Haq Ann Le Couteur
Aetiology
Genetic factors are important. It is likely that the phenotype results from several genes, possibly involving 2q and 7q, acting together. The British Twin Study estimated a broad heritability of 91–93% and a concordance of 69% in monozygotic twins. Psychological deficit theories have failed to identify a primary t deficit that could account for all of the features of the autistic phenotype. ‘Theory of mind’ has been implicated as a possible psychological mechanism underlying ASD.19 Biological deficit – the organic basis of ASD is well recognized, t but the biological deficits remain unclear. Physiological abnormalities of the gastrointestinal tract and immune system have been investigated as possible causal factors, but the only consistent finding is nonspecific raised blood serotonin.20
Increased awareness has placed great emphasis on the understanding of autism spectrum disorder (ASD). Some authors argue that ASD should be considered a common disorder of childhood.1,2 Autism was first described in 1943 by Kanner, and in 1944 Asperger described children with similar difficulties;3,4 at about the same time, other children with characteristics of ASD were described as having schizophrenia or infantile psychosis.5,6 In the 1960s and early 1970s, studies confirmed that children with behaviours similar to those described by Kanner could be reliably distinguished from mentally disabled children and those with other psychiatric disorders.7,8 The term ‘pervasive developmental disorder’ (PDD) was introduced by the American Psychiatric Association in 1980, and was adopted by the ICD9 and the DSM10 to cover both core autism and a broader range of autistic-like disorders. Recently, there has been a move to replace ‘PDD’ with ‘ASD’,11 reflecting the finding that there are more overlaps than differences between subcategories. ASD describes a constellation of features characterized by qualitative abnormalities in reciprocal social interactions and patterns of communication, and by restricted, stereotyped, repetitive interests and activities. These abnormalities are pervasive in all situations, but may vary in degree. It is now generally recognized that there is a spectrum of severity of the behavioural symptoms and intellectual ability, from severely impaired to high functioning. Use of the term ‘ASD’ reflects the continuity between autism and related disorders,12,13,14 and acknowledges the need to plan for assessment, diagnosis, intervention and support services for a larger number of individuals than was previously considered.
Clinical features and diagnosis
Many features of ASD appear to be consistent across cultures. A child in rural Guatemala may peer at a flag made from leaves and sticks in the same manner that a child in suburban Chicago squints at a flag made from McDonald’s swizzle sticks and sweetener packets. However, identical twins with ASD may vary in IQ by as much as 50 and lead very different lives, one driving his own car to work and the other requiring assistance with basic hygiene.21 In most cases, the parents of an affected child become concerned about abnormalities or delays in his or her second year. Often, the problems are not specific autistic features, but rather worries that the child is less talkative, or has temper tantrums or difficulties in settling, eating or sleeping. Many under-3s who will eventually meet the formal criteria for ASD do not yet show clear examples of restrictive or repetitive behaviours. Clinical diagnosis of autism requires evidence of three areas of deficit (social reciprocity, communication, and restricted, repetitive behaviours and interests) together with a report of some form of delay or deviance before 36 months of age. Not all individuals with ASD exhibit difficulties in all three areas at the same time. Communication – delay or deviance in development of language is an important feature of ASD. Language delay is usual. About 50% of individuals with a diagnosis of autism never achieve useful speech. Those who develop speech have difficulties with the social use of language, and speech abnormalities such as stereotyped phrases and pronoun reversal. Abnormalities of pitch and rhythm are more common in ASD than in general mental retardation/learning disability. ASD is also associated with deficits in non-verbal communication, including use of gestures such as pointing, nodding and showing. An affected child who wants a drink may have a tantrum or put the adult’s hand on the bottle to communicate the request, rather than using eye contact, gestures or vocalization. Deficits also occur in imitation, social play, spontaneous imaginative roleplay, and play with dolls or action figures. Shared play with other children may be impaired. Social interaction – deficits in reciprocal social interaction are a core feature of ASD.12 Infants and young children may not respond as expected to physical contact with a care-giver. Social use of smiling and other facial expressions may not develop or may appear inappropriate. Young children may not react to their carer’s voice, and it may be difficult to catch their attention.
Epidemiology
The prevalence of ASD varies between studies. According to recent reviews, however, ASD appears to affect about 60 children per 10,000 under 8 years of age, and 10–30 per 10,000 have narrowly defined autism.15,16,17,18 These estimates confirm that ASD is more common than was previously recognized. The observed increase may be at least partly a consequence of more complete ascertainment and the broader definition of ASD. Boys are 3–4 times more likely to have autism than girls, and the male preponderance is even more marked at the higher-functioning end of the spectrum.
Imtiazul Haq is Specialist Registrar in Child Psychiatry in the Fleming Nuffield Unit, Newcastle upon Tyne, UK. Ann Le Couteur is Professor of Child and Adolescent Psychiatry at the r University of Newcastle upon Tyne, UK.
MEDICINE
61
© 2004 The Medicine Publishing Company Ltd
CHILDHOOD, ADOLESCENCE AND BEYOND
With increasing age, social deficits may become more obvious. A child who lacks interest in other children can play successfully alongside them, but will experience problems as social expectations in shared play become more complex. Children with ASD often become isolated, are at risk of being bullied, and lack the social skills required to develop successful friendships. Repetitive behaviour and interests – children with ASD exhibit restricted, repetitive behaviours and interests. These may include unusual preoccupations (e.g. street signs, drainpipes), circumscribed interests (e.g. timetables, motorcycles) and attachment to unusual objects (e.g. a jar of lentils, belts, brushes). Other associated features include: • compulsions and rituals • unusual hand, finger or whole-body movements (stereotypical movements of hands and fingers are often within the peripheral vision) • repetitive use of objects • unusual interests in the sight, sound, smell or feel of objects or people. Children with ASD may also be preoccupied with sameness, and many are disturbed by changes in their routines. It is said that the form of the rituals and compulsive behaviours seen in ASD differs from that in obsessive–compulsive disorder (OCD). Many individuals with ASD are not upset by their compulsive behaviours and apparently make no effort to prevent them.
to the others.25,26 Behavioural and educational approaches have been emphasized, and involving parents as ‘co-therapists’ to foster social–communicative interactions may prevent secondary behavioural problems. There is emerging evidence that targeted interventions should begin as early as possible,27,28 to increase the likelihood that individuals with ASD will attain their full potential. The National Autism Plan for Children recommends that preschool children should have access to appropriate ASD-specific programmes for 15 hours per week. For both pre-school and school-aged children, the Family Care and Individual Education Plans ideally include clear ASD management strategies for staff and parents, and access to ASD-specific individual or small-group therapeutic educational opportunities as dictated by needs. There is no definitive evidence that pharmacological intervention alters the long-term prognosis. However, drugs combined with behavioural analysis and appropriate psycho-educational interventions may enable children with ASD to modify their behaviour in a manner that would have been impossible without their use.
Autism in adulthood
Autism is a lifelong disorder and the likelihood of complete independence is limited. Diagnosis in adulthood can be difficult and depends largely on the developmental history. Adults without mental retardation and with good verbal skills may participate in social interactions relatively well, but experience difficulties in forming relationships and coping with the social demands of the workplace. Most adults with ASD, even those with average or above-average abilities, require help in finding and keeping jobs and coping with responsibilities. Co-morbid psychiatric disorders (particularly depression and anxiety) are common, and access to psychiatric services for assessment and treatment is vital.
Associated conditions and differential diagnosis
IQ is less than 70 in 80% of individuals with narrowly defined autism, and at least one-quarter to one-third will develop epilepsy; onset of seizures peaks in early childhood and in adolescence. Co-morbid diagnoses include social anxiety and social phobias, attention deficit hyperactivity disorder, depression and OCD. Other conditions that can mimic the symptoms of ASD and should be differentiated include receptive–expressive language disorders, severe psychosocial deprivation, selective mutism, neurodevelopmental disorders (e.g. Tourette’s syndrome) and regressive disorders (e.g. tuberous sclerosis, childhood disintegrative disorder, Landau–Kleffner syndrome, Rett’s syndrome).
Asperger’s syndrome
Asperger’s syndrome is an ASD. The term is most commonly used to describe those with autism who do not have a learning difficulty. In both ICD-10 and DSM-IV, the essential criterion for diagnosis of Asperger’s syndrome is absence of delay in development of language and other adaptive skills. Individuals with Asperger’s syndrome usually have IQs in the normal range, and their verbal skill scores may be as good as or higher than non-verbal.
REFERENCES 1 Filipek P A et al. The screening and diagnosis of autistic spectrum disorders. J Autism Dev Disord 1999; 29: 439–84. d 2 Filipek P A et al. Practice parameters: screening and diagnosis of autism. Report of quality standards subcommittee of the American Academy of Neurology and the Child Neurology Society. Neurology 2000: 55: 468–79. 3 Frith U. Autism and Asperger syndrome. Cambridge: Cambridge University Press, 1991. 4 Ozonoff S, Pennington B F, Rogers S J. Executive function deficits in high-functioning autistic children: relationship theory of mind. J Child Psychol Psychiatry 1991; 32: 1081–105. y 5 Bender L. Childhood schizophrenia. Nervous Child 1942; 1: 138–40. d 6 Mahler M S. On childhood psychosis and schizophrenia: autistic and symbiotic psychosis. Psychoanal Study Child 1952; 7: 286–305. d 7 Rutter M, Greenfield D, Lockyer L. A five to fifteen year follow-up
Management
The UK National Initiative for Autism Screening and Assessment has been supported by the Royal College of Paediatrics and Child Health, the Royal College of Psychiatrists, the National Autistic Society and the All Party Parliamentary Group on Autism to produce the National Autism Plan for Children.11 The plan provides national guidelines for screening, investigation, early diagnosis and intervention in pre-school and primary school-aged children. These guidelines recommend that multi-agency assessment should be available in all areas and that, in addition to general and autismspecific developmental assessment, these should include psychometric, educational, communication, language, motor competency, behaviour and mental health assessments. Recent studies show that a valid clinical diagnosis can be made at age 2–3 years,14,22,23,24 though diagnosis is more difficult in young children who are more able and in those with significant developmental delay. Research has supported the effectiveness of various interventions, but there is no evidence that any one approach is superior
MEDICINE
62
© 2004 The Medicine Publishing Company Ltd
CHILDHOOD, ADOLESCENCE AND BEYOND
study of infantile psychosis. II. Social and behavioural outcome. Br J Psychiatry 1967; 113: 1183–99. y 8 DeMyer M K, Barton S, Norton J A. A comparison of adaptive, verbal and motor profiles of psychotic and non psychotic subnormal children. J Autism Child Schizophr 1972; 2: 359–77. r 9 WHO. ICD-10: classification of mental and behavioural disorders. Geneva: WHO, 1992. 10 American Psychiatric Association. Diagnostic and statistical manual of mental disorders. 4th ed. Washington: American Psychiatric Association, 1994. 11 Le Couteur A, ed. National autism plan for children. London: National Autism Society, 2003. 12 Wing L, Gould J. Severe impairments of social interaction and associated abnormalities in children: epidemiology and classification. J Autism Dev Disord 1979; 9: 11–29. d 13 Wing L. The autistic spectrum: a guide for parents and professionals. London: Constable, 1996. 14 Lord C, Risi S, Lambrecht L et al. The Autism Diagnostic Observation Schedule – Generic: a standard measure of social and communication deficits associated with the spectrum of autism. J Autism Dev Disord 2000; 30: 205–23. d 15 Baird G, Charman T, Baron-Cohen S. A screening instrument for autism at 18 months of age: a six-year follow-up study. J Am Acad Child Adolesc Psychiatry 2000; 39: 694–702. y 16 Scott F, Baron-Cohen S, Bolton P. Brief report: prevalence of autism spectrum conditions in children aged 5 to 11 years in Cambridgeshire, UK. Autism 2002; 6: 231–7. 17 Bertrand J, Mars A, Boyle C et al. Prevalence of autism in a United States population: the Brick Township investigations. Pediatrics 2001; 108: 1155–61. 18 Chakrabarti S, Fombonne E. Pervasive developmental disorders in pre-school children. JAMA 2001; 285: 3093–9. 19 Baron-Cohen S. Autism: a specific disorder of ‘mind blindness’. Int Rev Psychiatry 1990; 2: 79–88. y 20 McBride P A, Anderson G M, Hertzig M E et al. Effects of diagnosis, race and puberty on platelet serotonin levels in autism and mental retardation. J Am Acad Child Adolesc Psychiatry 1998; 37: 767–76. y 21 Lord C, Bailey A. Autism spectrum disorders. In: Rutter M, Taylor E, eds. Child and adolescent psychiatry. 4th ed. Oxford: Blackwell, 2002: 636–63. 22 Lord C, Magill-Evans J. Peer interactions of autistic children and adolescents. Dev Psychopathol 1995; 7: 611–26. 23 Cox A, Klein K, Charman T et al. Autism spectrum disorders at 20 and 42 months of age: stability of clinical and ADI-R diagnosis. J Child Psychol Psychiatry 1999; 40: 719–32. y 24 Stone W L, Lee E B, Ashford L et al. Can autism be diagnosed accurately in children under 3 years? J Child Psychol Psychiatry 1999; y 40: 219–26. 25 Dawson G, Osterling J. Early intervention in autism: effectiveness and common elements of current approaches. In: Guralnick M, ed. Effectiveness and early intervention: second generation research. Baltimore: Brookes, 1997: 307–26. 26 Jordan R, Jones G, Murray D. Educational interventions for children with autism: a literature review of recent and current research. (Research Report 77). London: Department of Education and Employment, 1998. 27 Handleman J S, Harris S. Preschool education programs for children with autism. Austin: Pro-Ed, 2000. 28 Howlin P, Charman A. Presentation to NIASA Working Group, 2001.
Eating disorders
J Treasure
Definitions
• Anorexia nervosa is characterized by refusal to maintain weight at or above a minimally normal weight (85% of expected weight for age and height, or body mass index (BMI) 17.5 kg/m2), or failure to exhibit the expected weight gain during growth. There is often associated intense fear of gaining weight, preoccupation with weight, denial of the current low weight and its adverse impact on health, and amenorrhoea. • Bulimia nervosa shares some features with anorexia nervosa (e.g. intense preoccupation with weight and shape), but is characterized by regular episodes of uncontrolled eating (> 1000 kcal) associated with various methods of counteracting weight gain (vomiting and laxative abuse are most common). • Various subtypes of eating disorders are defined within the spectrum of eating problems (Figure 1).
Epidemiology
Anorexia nervosa has a long history and is present in diverse cultural settings. The content of the psychopathology of anorexia nervosa varies with time and place; for example, weight phobia is not always present in non-Western societies. Bulimia nervosa became more common in the second half of the 20th century and was recognized as a new syndrome in Western societies in 1979.1 The mean incidence of anorexia nervosa in females is 19/100,000/year (about tenfold more than the male incidence).2 The highest prevalence is 0.5% in female teenagers. The prevalence of bulimia nervosa is 1% in young women. Overall, 5–10% of young women have some form of eating problem.
Aetiology and risk factors
Family, biological, social and cultural factors may have a role in the development and the maintenance of eating disorders. The evidence for such risk factors is collated in two recent systematic reviews.3,4 • The risk of eating disorders in first-degree relatives of affected individuals is increased tenfold, and twin studies suggest that this is because of inherited factors. Preliminary studies suggest that a region on chromosome 1 is linked with anorexia nervosa5 and on chromosome 10 with bulimia nervosa.6
J Treasure is Director of the Eating Disorder Unit and Professor of Psychiatry at Guy’s, King’s and St Thomas’ Medical School, London, UK.
MEDICINE
63
© 2004 The Medicine Publishing Company Ltd
