Autism and Asperger Syndrome

Preparing for Adulthood

Patricia Howlin

• Publisher: Routledge
• Year: 2004
• ISBN:
  9781134391400
• Edition: 2
• Topic: Medicine
• Subtopic: Medical Theory, Practice & Reference

Autism and Asperger Syndrome reviews what is known about adults with autism in terms of their social functioning, educational and occupational status. Focusing mainly on the problems experienced by high functioning people with autism - and those working with and caring for them - the book offers practical ways of dealing with their difficulties. Each chapter makes use of clinical case material to illustrate the kinds of problems faced and ways in which they may be overcome. First-hand accounts from people with autism are included and links with psychiatric illness in later life are explored.This updated edition is helpful to both professionals and families with autistic children and has been completely updated to take account of the latest research in the field. It also includes an additional chapter on the differences between autism and Asperger syndrome.

1 Is there a distinction between autism and Asperger syndrome?

Historical Background

At much the same time that Kanner was writing about children with autism in the United States (Kanner 1943) Asperger, in Austria, was describing the group of children who eventually came to be named after him (Asperger 1944). With an ocean and a world war between them, collaboration was hardly to be expected. However, gradually clinicians and researchers began to recognise the striking similarities between these two conditions. Both authors described difficulties with reciprocal social interaction, communication, and ritualistic and stereotyped routines, usually beginning within the first two years of life. Both stressed the contrast between the children’s profound social deficits and their ‘purposeful, and intelligent relation to objects’ (Kanner 1946). Behavioural problems such as aggression, destructiveness and outbursts of temper were also noted, as were various developmental problems. Interestingly, too, both accounts contained descriptions of other family members who exhibited ‘autistic’ traits. It is true that Asperger’s accounts tend to focus on more able individuals, whilst many of Kanner’s children were seen to have intellectual impairments. Nevertheless, Asperger also referred to individuals ‘with considerable intellectual retardation’ and noted that ‘The fate of (these) cases is often very sad’. Likewise, Kanner described some individuals who had achieved highly, both in terms of education and employment, in adult life.

Linguistic and political considerations meant that Asperger’s work received little publicity: papers published in German gained little favour in much of Europe or America in the years shortly after the Second World War. In contrast, Kanner’s accounts were rapidly published in reputable journals. It was not until 1981, when Lorna Wing first brought Asperger’s original writings to the attention of clinicians, that the condition began to be more widely recognised. It was first included within the major classification systems, under the broader category of Pervasive Developmental Disorders (PDD), in the early 1990s (DSM-IV 1994, ICD-10 1993). Wing’s main purpose for highlighting Asperger’s work was to draw attention to the fact that typically autistic features could be found in individuals with well-developed language and cognitive skills as well as in those of low IQ. But as many clinicians failed to recognise their problems as falling within the autistic spectrum, access to correct diagnosis and treatment was often denied. Wing considered the term Asperger syndrome to be a useful ‘shorthand’ label, indicating that autism could affect people with a high IQ and extensive vocabulary as well as those who had no language and significant learning difficulties. In other words, Asperger syndrome represented the more cognitively able end of the ‘autistic continuum’.

There can be no doubt that her work resulted in many high-functioning individuals finally obtaining an appropriate diagnosis. Nevertheless, two decades later Wing has expressed doubts about the wisdom of introducing the term into clinical practice (Wing 2000). The ‘Pandora’s box’ she opened has, she believes, resulted in a ‘belief that Asperger syndrome and autism are different conditions – quite the opposite of my intention’. Her original purpose – to emphasise the fact that there was no evidence for a distinction between Asperger syndrome and autism – has frequently been overlooked. Instead, the question of whether the two are different conditions (albeit part of the same spectrum of disorders) has been a source of continuing debate over recent years, as recent volumes by Klin et al. (2000) and Schopler et al. (1998) testify.

Formal diagnostic criteria for Asperger syndrome note that the social deficits and ritualistic and stereotyped behaviours have the same features as in autism (World Health Organization 1992, American Psychiatric Association 1994). The two main distinguishing features are the presence of relatively normal cognitive skills and the lack of early language delays in the Asperger group (see Table 1.1). Although Volkmar and Klin (2000) state that these diagnostic criteria should be considered as ‘tentative and in need of empirical validation’, both systems are explicit that Asperger syndrome and autism are mutually exclusive categories. DSM-IV guidelines also specify that if criteria for autism are met then this diagnosis takes precedence over Asperger syndrome, However, as a number of authors have pointed out, if strict DSM/ICD criteria are applied, a diagnosis of Asperger syndrome becomes unlikely or even impossible (Eisenmajer et al. 1996, Ghaziuddin et al. 1992a, Manjiviona and Prior 1995, Mayes et al. 2001, Miller and Ozonoff 1997, Szatmari et al. 1994).

Table 1.1 ICD-10 research criteria for Asperger syndrome

Research into the association between autism and Asperger syndrome

In a review of recent studies comparing individuals with Asperger syndrome and high-functioning autism (HFA), it was apparent that inadequate group matchings, small samples, and above all a lack of agreement on diagnostic criteria made it almost impossible to reach a definite conclusion about the similarities and/or differences between the two conditions (Howlin 2003). The review included only those studies in which a direct comparison between individuals with high-functioning autism (IQ 70+) and Asperger syndrome had been conducted and in which diagnostic criteria and measures of IQ were adequately specified. However, as can be seen from Tables 1.2 and 1.3, in many cases strict DSM-IV criteria for Asperger disorder were not used, principally because, as noted above, if these guidelines are followed only a minority of individuals meet the necessary criteria. Instead, researchers tended to use the term for individuals who, though often meeting criteria for autism, had not shown early language delays. Many studies also failed to match participants with Asperger syndrome and those with high-functioning autism on the basis of IQ. Thus, any reported differences between the groups could be due to cognitive disparities rather than a true diagnostic differentiation.

Table 1.2 Summary of studies comparing individuals with Asperger syndrome and high-functioning autism (Asperger syndrome groups higher IQ)

Table 1.3 Summary of studies comparing individuals with Asperger syndrome and high-functioning autism matched for full-scale IQ

Nevertheless, even when the Asperger groups were of higher overall IQ than the HFA groups, the differences were often small and inconsistent. Among the reports with a focus on early history, general clinical severity or motor problems, most reported few differences. Ghaziuddin and Butler (1998) identified more motor difficulties in their HFA group, but the difference disappeared when IQ was controlled for and both groups were relatively impaired compared to population norms. Szatmari et al. (1994) found that early group differences in language abilities diminished over time, and Gilchrist et al. (2001) also noted that initial differences in symptom severity tended to decline with age. Thus, although there were differences on ADI scores in early childhood (with the HFA group showing more difficulties) there were no significant differences in adolescence and early adulthood. Of five reports on neuropsychological and linguistic functioning the Asperger groups generally showed superior verbal skills; but, again, these differences tended to disappear when IQ was controlled for. Evidence for differences in behavioural or psychiatric disturbance was also inconsistent, with Ghaziuddin et al. (1995) and Tonge et al. (1999) reporting increased pathology in the Asperger groups, although this was not found in the study of Kim and colleagues (2000).

The findings were variable even when the groups were matched for IQ. Of five reports on early history and general clinical characteristics, three suggested higher rates of problems in the HFA groups, but Ozonoff and colleagues (Ozonoff et al. 2002) found that these differences were not necessarily maintained as children grew older. Stereotyped and ritualistic behaviours occurred in both groups, but in the Ozonoff study there was greater evidence of special interests in the Asperger group whilst insistence on sameness was more common in the autism group. Although many clinical accounts of individuals with Asperger syndrome have reported problems of motor coordination, the only study to find evidence of increased clumsiness was that of Gillberg and Gillberg (1989).

Amongst those studies examining neuropsychological or linguistic functioning, several studies reported higher verbal skills in the Asperger groups, even though the groups had been matched for overall IQ. There were few differences in scores on tasks of social understanding, theory of mind or executive function, and although individuals with Asperger syndrome showed some superiority in these areas in Ozonoff ’s study, this difference may have been related to their higher verbal skills. Rates of psychiatric disturbance did not differ markedly, although Szatmari and colleagues found that individuals with HFA tended to show more bizarre preoccupations.

Most of the comparative studies of autism and Asperger syndrome have involved children or adolescents, but there were indications from several (Gilchrist et al. 2001, Ozonoff et al. 2002, and Szatmari et al. 1994) that even if differences could be identified in childhood, these tended to disappear with age. To investigate this possibility further, Howlin (2003) compared past history and current functioning in adults with a diagnosis of HFA or Asperger syndrome. Diagnosis of an autistic disorder was confirmed on the basis of the Autism Diagnostic Interview – Revised (ADI-R; Lord et al. 1994) and all participants had a non-verbal IQ of 70 or above. The sample comprised thirty-four individuals who had been delayed in their language development (the HFA group) and forty-two who had shown no early language delays (the Asperger group). The average age in both groups was around twenty-six to twenty-seven years.

The findings indicated that parents did report certain differences between the groups when they were younger. Parents of children with autism were initially more concerned about language delays. Children with Asperger syndrome tended to be older when parents first noted abnormalities in their development (average age twenty-one months as compared to an average of fifteen months in the autism group), and their parents’ first concerns were split fairly evenly between general behaviour problems, ritualistic and stereotyped behaviours/interests, and motor delays/difficulties. However, on the Autism Diagnostic Interview (ADI-R) parental ratings of their children’s development suggested that these early differences decreased over time. Thus, by the age of four to five years, no significant group differences were found in social or communication skills. As adults, average IQ scores in both groups were almost identical (100 in the HFA group and 101 in the Asperger group) and age-equivalent scores on tests of language use and comprehension were also similar, at around fifteen to sixteen years. On the ADI-R, ratings of social functioning, communication and ritualistic/stereotyped behaviours were remarkably close, and outcome in terms of friendships, employment and independent living did not differ. Only two individuals in the Asperger group and three in the autism group were reported to have developed close friendships, although rather more (ten with autism, fifteen with Asperger syndrome) had acquaintances whom they met outside home or work. Three men (two autistic, one Asperger) were married or living with a partner, and one of the married men in the autism group had children. One woman in the Asperger group was divorced. The majority in both groups (nineteen with autism, twenty-six with Asperger syndrome) still lived with their parents, and of those who did live independently most (seven out of eleven in the autism group; nine out of fifteen in the Asperger group) continued to require support either from their families or social services. Three people with autism and one with Asperger syndrome were in specialist residential provision, and one man with autism was in a long-stay psychiatric hospital. In terms of employment, fifteen individuals in each group had never had a job, and only two in each group had relatively well-paid, permanent employment. Three individuals in each group were in sheltered placements or worked with the family firm; the remainder was in short-term, low-paid or voluntary posts that did not provide them with sufficient money to live independently.

Even ratings of motor clumsiness, a variable that has frequently been claimed to characterize individuals with Asperger syndrome (see Volkmar and Klin 2000), failed to differentiate between the groups. The number of individuals with an additional psychiatric diagnosis was also similar in both groups, with depressive disorders appearing to be the most common. Use and understanding of language was somewhat better among the Asperger adults, although the differences were small and insignificant. The only area in which a significant group difference emerged was in academic attainment, with more individuals among the Asperger group obtaining graduate or postgraduate qualifications. However, this advantage in terms of academic attainment did not seem to have resulted in higher levels of achievement in later life.

The finding that early differences between individuals with a diagnosis of Asperger syndrome or high-functioning autism may reduce with age is supported by a number of other recent studies. Gilchrist et al. (2001), for example, found that scores on the Autism Diagnostic Interview, which had differed significantly between individuals with autism and Asperger syndrome at the age of four to five years, had disappeared by adolescence or early adulthood. Szatmari (2000) has suggested that any differences identified in the early years may not represent a true diagnostic ‘splitting’ between the groups but instead are probably related to the severity of early language delays, which can lead to children following somewhat different trajectories over time. Both he and Wing (2000) have reported that young children with apparently typical autism may ‘shift’ to follow an ‘Asperger-type’ pathway subsequently, especially if they develop good language. If, on the other hand, language development is markedly delayed, children are likely to remain at a disadvantage in their ability to ‘catch up’ linguistically and this in turn will affect many other aspects of their cognitive and social functioning.

A further recent review of research in this area by Macintosh and Dissanayake (2004) also suggests that there is no empirical basis for classifying Asperger syndrome as a condition distinct from high-functioning autism. However, comparisons between these two groups will only produce meaningful conclusions if participants are appropriately matched for intellectual level. The age at which data are collected will also influence the findings, as differences between the two groups seem to become less evident as they grow older. The superiority of individuals with Asperger syndrome with respect to some aspects of their language is not enough to indicate a distinction between the two conditions. Instead, the fact that individuals with a diagnosis of autism are, by definition, so much further behind in their early language development may be the prime reason for the relative severity of their communication difficulties in later life.

It is important to be aware that the distinction made between the two conditions in DSM-IV and ICD-10 criteria does not rest on sound empirical data but is based largely on clinical descriptions. Clearly, there are major differences between individuals with autism who are of normal IQ and language ability and those of very low IQ with little or no language. These differences also have important implications for service provision. However, within the higher-functioning range, experimental studies have failed to identify distinct subgroups. Moreover, diagnostic instruments designed for more able individuals, such as the Asperger Syndrome Diagnostic Interview (Gillberg et al. 2001), the Autism-Spectrum Quotient (Baron-Cohen et al. 2001) or the Childhood Asperger Syndrome Test (Scott et al. 2002) have failed to delineate any specific characteristics that differentiate between Asperger syndrome and autistic individuals of normal intelligence. Furthermore, the finding that the language abilities of high-functioning individuals, whether or not they had marked delays in their early language development, are frequently well below chronological age in adulthood, raises further problems in terms of the validity of the DSM-IV/ICD-10 distinction. (Howlin 2003). Thus, although Asperger syndrome is, by definition, not associated with impairments in spoken language, more detailed assessments indicate that, in many cases, this criterion is not met as comprehension, vocabulary and social use of language remain well below chronological age levels.

The results of comparative studies are also of clinical importance since they not only highlight the lack of any substantial difference between the two diagnostic groups in adulthood but also illustrate the poor prognosis, even for high-functioning individuals within the autistic spectrum. Despite having IQ scores well within the normal range (and sometimes reaching quite high academic levels) the majority of individuals in both the Asperger and high-functioning autism groups studied by Howlin (2003) had no close friends, remained highly dependent on their families for support and had low employment status. Larger-scale prospective studies are still required in order to clarify the extent and nature of the possible differences between these two relatively high-functioning groups. However, for the present, the weight of evidence seems to suggest that there is no marked distinction between Asperger syndrome and individuals with autism who have developed functional language and whose IQs lie within the normal range.

Many researchers have now come to the conclusion that most research in this area points firmly to a dimensional, rather than a categorical, view of autistic-spectrum disorders. As Leekham and her colleagues (2000) point out: ‘It is time to move away from potentially circular attempts to differentiate Asperger syndrome and autism… in practice, the most useful indication of current needs and future prognosis is overall level of ability’. Certainly, there is no evidence to support the view that individuals with a diagnosis of Asperger syndrome should be deprived of the support and services that are available for those with a diagnosis of autism, or that educational and management programmes should substantially differ. Despite this, the differential diagnosis can have implications for services, with individuals with Asperger syndrome frequently being denied the level of support offered to those diagnosed as having autism. For example, in the United States, statutory educational and support services that are available for children with autism may be denied to children who are given a diagnosis of Asperger syndrome. In the United Kingdom, a recent White Paper by the Department of Health (2001), supposedly designed to improve support systems for all individuals with intellectual impairments, specifically excludes from its remit individuals with autistic-spectrum disorders ‘who may be of average or even above average intelligence – such as those with Asperger syndrome’.

Despite her concerns about the Pandora’s box she unwittingly opened Wing (2000) believes that the introduction of the term ‘Asperger syndrome’ did serve one very important purpose: that of widening prevailing concepts of autistic-spectrum disorders. She and her colleagues (Leekham et al. 2000) also believe that the label, if used flexibly, is of practical value in explaining the needs and problems of children and adults who have autistic features but who are of relatively high intelligence, speak grammatically and are not socially aloof. Parents of more able individuals often tend to find the diagnosis more acceptable than one of autism, and as they get older it is clear that many high-functioning individuals within the autistic spectrum prefer to use this label to describe themselves. Higher-functioning children and adults with autism have social, educational, occupational and residential needs that are often quite different to those of individuals with more severe intellectual disabilities, even though the basic principles of an autism-specific approach to intervention may apply to both groups. If the use of the ‘Asperger’ label enables them to gain access to appropriate support, well and good. However, it is of little value if used to discriminate against and deny services to those who need them, or to trivialize their difficulties. Asperger syndrome is often referred to as a ‘mild form of autism’. Nothing could be further from the truth. For, while the cognitive impairments may be mild, the social difficulties experienced by these individuals may be just as restrictive and damaging as is the case for those who are intellectually severely impaired. Indeed, their greater awareness of their problems may lead to increased personal distress. A recent follow-up study by Gillberg and his colleagues, for example (Billstedt 2003), has indicated that quality of life ratings for more able adults with autism are actually lower than for those with moderate to severe intellectual impairments.

There is also little value in the label if used incorrectly. Parents given this diagnosis will understandably expect their son or daughter to have a much better chance of making progress than if they have been given a diagnosis of autism. It is unforgivable, therefore, for clinicians to use the term without careful consideration of the child’s level of functioning, even if this is done to ‘make parents feel better’. The parents of five-year-old Seth, for example, were suing the local education authority for failing...

Table of contents

• Cover Page
• Autism and Asperger Syndrome
• Title Page
• Copyright Page
• Dedication
• Figures
• Tables
• Foreword
• Acknowledgements
• Introduction
• 1 Is there a distinction between autism and Asperger syndrome?
• 2 Outcome in autism
• 3 Interventions for autism
• 4 Problems of communication
• 5 Social functioning in adulthood
• 6 Stereotyped, ritualistic and obsessional behaviours
• 7 Secondary education
• 8 Further educational provision
• 9 Coping with and finding employment
• 10 Psychiatric disturbances in adulthood
• 11 Legal issues
• 12 Sexual relationships and marriage
• 13 Enhancing independence
• Bibliography