What is Autism?
Autism spectrum disorder (ASD) is a pervasive developmental disorder characterised by a triad of symptoms; impaired social skills, rigid communication style & characteristic repetitive and ritualised behaviours. Although, it is considered a lifelong condition, one’s impairments can significantly improve with appropriate awareness, support and, where required, intervention.
ASD could be considered an umbrella term for autistic conditions as seen in the ICD and DSM diagnostic manuals. ICD-10 outlines eight conditions under F84: childhood autism, atypical autism, Rett’s syndrome, other childhood disintegrative disorder, overactive disorder associated with mental retardation and stereotyped movements, Asperger’s syndrome, other pervasive developmental disorders and pervasive developmental disorder, unspecified. DSM-IV set out five conditions within chapter one’s description of pervasive developmental disorders: autistic disorder, Rett’s disorder, childhood disintegrative disorder, Asperger’s syndrome and pervasive developmental disorder - not otherwise specified, including atypical autism.
The most recent version of the DSM diagnostic criteria, DSM-5 combined autism, Asperger’s syndrome and pervasive developmental disorder into a single diagnosis and changed the name of this group from ‘pervasive developmental disorders’ to ‘autism spectrum disorder’ (American Psychiatric Association, 2013). Although the category remains broad, DSM-5 no longer provides differing criteria for each condition, instead a single set of criteria can be used to diagnose ASD.
The ICD-10 and DSM-5 criteria:
Diagnostic Criteria for Subtypes of Autism Spectrum Disorder
International Classification of Diseases-10 (World Health Organisation, 1992)
‘A. Abnormal or impaired development is evident before the age of 3 years in at least one of the following areas:
1. receptive or expressive language as used in social communication.
2. the development of selective social attachment or of reciprocal social interaction.
3. functional or symbolic play.
B. A total of at least six symptoms from (1), (2) and (3) must be present, with at least two from (1) and at least one from each of (2) and (3)
1. Qualitative Impairment in social Interaction are manifest in at least two of the following areas:
a) failure adequately to use eye-to-eye gaze, facial expression, body posture and gestures to regulate social interaction.
b) failure to develop (in a manner appropriate for mental age, and despite ample opportunities) peer relationship that involve a mutual sharing of interests, activities and emotions.
c) lack of socio-emotional reciprocity as shown by an impairment or deviant response to other people's emotions; or lack of modulation of behaviour according to social context; or a weak integration of social, emotional and communicative behaviours.
d) lack of spontaneous seeking to share enjoyment, interests or achievements with other people (e.g. a lack of showing, bringing or pointing out to other people objects of interest to the individual).
2. Qualitative abnormalities in communication as manifest in at least one of the following areas:
a) delay in or total lack of development of spoken language that is not accompanied by an attempt to compensate through the use of gestures or mime as an alternative mode of communication (often preceded by a lack of communicative babbling).
b) relative failure to initiate or sustain conversational Interchange (at whatever level of language skill is present) in which there is reciprocal responsiveness to the communications of the other person.
c) stereotyped and repetitive use of language or idiosyncratic use of words or phrases.
d) lack of varied spontaneous make-believe play or (when young) social imitative play.
3. Restricted, repetitive and stereotypes patterns of behaviour, interests and activities are manifested in at least one of the following:
a) an encompassing preoccupation with one or more stereotyped and restricted patterns of interest that are abnormal in content of focus, or one or more interests that are abnormal in their intensity and circumscribed nature though not in their content or focus.
b) apparently compulsive adherence to specific non-functional routines and rituals stereotyped and repetitive motor mannerisms that involve either hand or finger flapping or twisting or complex whole body movements.
d) preoccupations with part-objects of non-functional elements of play materials (such as their order, the feel of their surface or the noise or vibration they generate).
The clinical picture is not attributable to the other varieties of pervasive developmental disorders, specific development disorder of receptive language with secondary socio-emotional problems, reactive attachment disorder or disinhibited attachment disorder, mental retardation with some associated emotional or behavioural disorders, schizophrenia of unusually early onset and Rett’s syndrome’.
A. Abnormal or impaired development is evident at or after the age of 3 years.
B. There is insufficient demonstrable abnormalities in one or two of the three areas of psychopathology required for the diagnosis of childhood autism (namely reciprocal social interactions, communication or restrictive, stereotyped, repetitive behaviours).
C. Atypical autism constitutes a meaningfully separate condition from childhood autism.
A. Diagnostic criteria 1 - 3 of B are fulfilled for childhood autism.
B. No evidence of general delay or retardation in language or cognitive development.
C. Generally associated with normal intelligence.
Diagnostic and Statistical Manual of Mental Disorders-5 (American Psychiatric Association, 2013)
Autism spectrum disorder (ASD)
A. Persistent deficits in social communication and social interaction across multiple contexts, as manifested by the following, currently or by history:
· Deficits in socio-emotional reciprocity.
· Deficits in non-verbal communicative behaviours used for social interaction.
· Deficits in developing, maintaining and understanding relationships.
B. Restricted, repetitive patterns of behaviour, interests, or activities, as manifested by at least two of the following, currently or by history:
· Stereotyped or repetitive motor mannerisms, use of objects or speech.
· Insistence on sameness, inflexible adherence to routines or ritualised patterns of verbal or non-verbal behaviour.
· Highly restricted, fixated interests that are abnormal in intensity or focus.
· Hyper- or hypo- reactivity to sensory input or unusual interest in sensory aspects of the environment.
C. Symptoms must be present in early developmental period.
D. Symptoms cause clinically significant impairment in social, occupational or other important areas of current functioning.
E. These disturbances are not better explained by intellectual or global developmental delay.
Autism and Physical Illness
Erroneously early researchers thought that individuals with autism spectrum disorder did not perceive pain and did not communicate their distress; perhaps lacking the ‘social inclination’ to do so (Lainhart 1999). In the mid 2000’s, researchers hypothesised that those with ASD actually have difficulty reporting physical ailments and instead express pain and physical distress as agitation and / or behavioural disturbance (Russell 2005). Although current literature on physical illness in adults with ASD is sparse, a 2016 study by O’Rourke revealed a prevalence rate of 84% for at least one physical health condition among adults with ASD. Atopy was the most commonly diagnosed condition and epilepsy was also notably more common in those with ASD.
Although historically considered almost diagnostic for ASD, eating disturbance is now known to occur in approximately 25% of adults with ASD. Restricted dietary repertoire was most commonly reported, followed by reduced appetite, picky eating, eating only a single meal per day, only eating when alone, unhealthy dietary choices, binge-eating and overeating (O’Rourke 2016). Available research in relation to gastrointestinal disease in ASD is varied and controversial. However, available literature would suggest that previously reported higher rates of gastrointestinal disease in individuals with ASDs were greatly exaggerated.
Sleep is a relatively well-researched topic in ASD. In fact, it has been referred to as the second most researched area of ASD comorbidity, only surpassed by epilepsy (Mannion 2014). Sleep studies in normal IQ infants with ASD have shown that 90% of sleep difficulties start at an early age including difficulty falling asleep, more frequent night waking and early morning waking (Øyane 2005). Studies of school-age children with ASD have noted difficulties with bedtime resistance, increased sleep latency, poor sleep maintenance, early morning waking, reduced sleep time and quality, increased night waking and irregular sleep patterns in 50% - 80% of subjects (Øyane 2005, Limoges 2005, Canitano 2007, Reynolds 2011). Insomnia rates of 36% have been reported in the child population, most commonly middle insomnia, followed by initial insomnia (Mattila 2010). Adolescent and young adult studies also identify a high prevalence of sleep disorders (80%) including low sleep efficiency, short total sleep time, long sleep latency, more frequent shifts into REM sleep from waking and increased REM sleep disruption (Ghaziuddin 2002a, Øyane 2005).
In general, it is acknowledged that motor skill deficits are frequently observed in patients with ASD with a prevalence of 21% - 100% (Gowen 2012). Asperger described awkwardness as typical in autistic psychopathy (Wing 2002a, Barnhill 2007, Raja 2009) while Kanner (1943) noted that several children under his care were somewhat clumsy in gait with gross motor deficits but all were skilled in fine motor movements. Although not included in the DSM-5 diagnostic criteria, clumsiness is commented upon in the ICD-10’s description of Asperger’s syndrome (World Health Organisation 1992). Wing (1981) observed poorly co-ordinated movements, odd posture and abnormal gait while more recently Vannucchi (2014) described clumsiness and illegible handwriting as atypical features of Asperger’s syndrome and Van Wijngaarden-Cremers (2014) noted clumsiness in the case of a 14 year old girl with Asperger’s syndrome and comorbid drug addiction.
Autism and Mental Illness
Increasingly autism spectrum disorder is associated with a higher prevalence of mental illness than seen in the general population (Stewart 2006, Nylander 2008, Raja 2008). Roy (2015) noted a lifetime prevalence of one or more comorbid psychiatric illness in 70% of adults with High-functioning ASD.
Rates of anxiety spectrum disorders are higher in the ASD population compared to the general population, including obsessive compulsive disorder, generalised anxiety disorder, social phobia and agoraphobia (O’Rourke 2016).
Rates for mood disorders range from 24% - 53% (Ketelaars 2008, Hofvander 2009, Stunz 2014). Lifetime prevalence of major depressive disorder is 70% - 77%, recurrent depression 50%, current depressive episode 30% and dysthymia 8% (Cath 2008, Lugnegård 2011, Joshi 2013).
O’Rourke (2016) identified a prevalence rate of 25% for deliberate self-harm and a rate of 16% for self-injurious behaviour in autistic adults.
Schizoid, schizotypal, paranoid, obsessive-compulsive, anxious-avoidant and dependent personality styles are more common in autistic adults than in the general population (Anckarsäter 2006).
Schizophrenia has a lifetime prevalence of 0.30% - 0.87% in the general population (Perälä 2007, Van Os 2009). Rates among those with ASD are less clearly defined. As early as the 1940’s, Asperger noted that only one of the 200 cases he studied developed schizophrenia (Wing 1981). Volkmar and Cohen (1991) restarted the debate on comorbidity between ASD and schizophrenia when they identified only a single patient with schizophrenia from 163 cases assessed. Volkmar and Cohen (1991) described schizophrenia as rare in those with ASD, ‘no more commonly observed together than would be expected by chance’.
While research on eating disorder in autistic adults is scarce, it is agreed that ASD is over-represented in the anorexia nervosa population (Oldershaw 2011). A single study was identified which showed a prevalence rate of 5% for comorbid ASD and eating disorder. The comparable occurrence rate in the general population is anorexia nervosa 0.9% and bulimia nervosa 1.5% for women and anorexia nervosa 0.3% and bulimia nervosa 0.5% for men (Hudson 2007).s