Basic and advanced knowledge on autism - Module 1

1. INTRODUCTION

Autism is a neurodevelopmental disorder characterized by deficits in social communication and social interactions, as well as the presence of limited, repetitive and stereotypical patterns of behavior, interests and activities. Although all people with autism have deficits in social interactions and stereotypical behavior, there are huge variations in the severity of these symptoms. That is why the term autism spectrum disorder is used, which should indicate the variability of symptoms and heterogeneity of individuals with this disorder. Earlier classification systems of the World Health Organization and the American Psychiatric Association used the term "pervasive developmental disorders", and this group of disorders, in addition to autism, included disintegrative childhood disorder, Rett syndrome, Asperger's syndrome and Pervasive Developmental Disorder - Not Otherwise Specified. Today, it is known that Rett syndrome is a rare neurological, genetic disorder, which has only superficial similarities to autism, which is why they are no longer classified in the same category of disorders as autism. All other pervasive developmental disorders are classified into a unique category of autism spectrum disorders. 

Autism spectrum disorder occurs in early childhood. In some children, the symptoms of autism, although not quite specific, can manifest in the first year of life. In the case of regressive or secondary autism, the first symptoms appear after a phase of typical or seemingly typical development. It happens that, in children with milder forms of autism, some symptoms are not noticeable at first, until the social demands placed on them become large enough. Also, there are people with high-functioning autism who try to mask their symptoms, which makes their recognition difficult in adolescence and adulthood. In the text that follows, we will describe the symptoms of autism in the field of social communication and stereotypical patterns of behavior. It should be noted that none of these symptoms are specific to autism alone, and that not all people with autism will have each of these symptoms.

2. SOCIAL COMMUNICATION DISORDER

Some children with autism have functional language impairment, which means that they are minimally verbal, i.e. they use speech at the level of individual words or phrases to express personal desires and needs. Research on a subsample of verbal children with autism shows that about half of these children have structural language impairment, in the domain of phonological abilities (pronunciation of sounds and syllables) and/or in the field of morphosyntax (grammatically correct speech and sentence formation). Other verbal children with ASD have well-developed structural aspects of language (Loucas et al., 2008).

3. RESTRICTED, REPETITIVE PATTERNS OF BEHAVIOR, INTERESTS, OR ACTIVITIES

In order to diagnose ASD, in addition to social communication disorders, it is necessary that there are pronounced symptoms in at least two of the four listed areas.

3.1. Stereotyped or repetitive movements, use of objects or speech

Motor stereotypes are purposeless patterns of movement that are continuously repeated in a certain period of time, in the same form and in different circumstances. They can occur in the form of simple body movements (e.g. body rocking, repetitive jumping, hand flapping, and finger-wiggling, whirling ...) or in the form of complex autistic mannerisms. Among the most significant factors influencing the occurrence of motor stereotypes in people with autism are: age (younger children have more motor stereotypes than older children), intellectual disability and severity of autism (Melo et al., 2020). Children with autism often use objects in a stereotypical way. They usually arrange objects in a precisely determined order, rotate, touch or tap objects, although in some cases more complex forms of repetitive use of objects are manifested. Stereotypes can also be manifested in speech, most often in the form of current and delayed echolalia, the use of idiosyncratic phrases (i.e. expressions specific to that person), repetitive questioning, verbal perseverations, etc.

3.2. Insistence on sameness, routines, and rituals

People with autism can show great resistance to change. Insistence on sameness manifests itself in different ways. The child asks to always eat the same food, to wear the same clothes, to go the same way to school and back, and is upset because of the slightest changes in the daily routine. Thus, for example, a school-age child may show resistance due to a change of classroom (e.g. due to going to the gym or dining room), teachers, school, environment, etc. People with low-functioning autism are somewhat more prone to simpe motor mannerisms, while complex routines and rituals are characteristic of people with high-functioning autism. Stereotypical behaviors, routines, and rituals usually help a person with autism cope with unpredictable and uncontrolled sensory inputs and the growing stress that accompanies inadequate sensory stimulation. Hence, it is not surprising to find that there is a positive correlation between different forms of stereotypical behavior, on the one hand, and anxiety disorder, on the other (Russell et al., 2019).

3.3. Highly restricted, fixated interests

People with autism may have very limited interests, which are considered atypical in focus or intensity. If the subject of interest is not common to the age and environment to which the child belongs, such interests are atypical in focus. For example, a person with autism may be fascinated by turning the washing machine drum, tree twigs, shadows, spinning objects, and the like. On the other hand, some people with autism may have relatively typical interests in national flags, railway traffic, specific scientific disciplines, etc, but such interests are very high in intensity, so they spend too much time doing activities related to the subjects of their interest. Limited interests are usually associated with perseverance in speech, excessive elaboration of always the same topic, and resistance to change. If a student with autism exhibits atypical interests in one area, consideration should be given to how they can be used to study other subjects and develop social interests. It is a much better strategy than banning or changing them. In rare situations, limited interests are of such a nature as to violate legal norms, in which case they should be redirected with the support of autism experts.

3.4. Hyper- or hyporeactivity to sensory input

Altered sensory processing is an important feature of the clinical picture of ASD. Different forms of behavior indicate altered processing of sensory input (smelling objects; fascination with texture, sound, smell, vibration, and other sensory aspects of toys; avoiding clothing and food of a certain texture, etc.). Sensory processing disorder covers the entire autism spectrum and is present in all age groups. It can have a significant impact on everyday life activities, school achievements, work efficiency, social relations and quality leisure time. People with autism may be overly sensitive to some sensory stimuli. It is relatively common for a child to be afraid of the sounds of household appliances, vehicles and environmental noise, trying to achieve sensory regulation by covering the ears. On the other hand, some children are hyposensitive, which is manifested, for example, in their reduced sensitivity to heat, cold or pain. It should be borne in mind that different people with autism may react to sensory overload in completely different ways. Some people will completely "shut down", which from the observer's point of view may seem as hyporeactivity, rather than as excessive sensitivity. In others, the "struggle" with sensory stimulation will take the form of self-stimulating and repetitive behavior, and there are those who will focus all their attention only on some stimuli, blocking access to all other, less desirable stimuli (Crespi, 2021).

4. HETEROGENEITY

The autism spectrum disorder is very heterogeneous, not only in the domain of clinical manifestations, different time of onset of first symptoms and uneven gender distribution, but also in presumed risk factors and etiopathogenesis. Autism can be accompanied by any form of intellectual and speech-language functioning. Therefore, five diagnostic subcategories for ASD have been identified in the World Health Organization’s International Classification of Diseases ICD-11 (WHO, 2018). Three subcategories are persons with a harmonized relationship of intellectual and linguistic functioning: individuals with intellectual disabilities without developed speech; people with intellectual disabilities and functional language impairment, as well as people of average intelligence with well-developed speech and language skills. There are also two discrepant profiles. The former are persons of preserved intelligence with functional language impairment, while the latter profile of reduced intellectual functioning accompanied by well-developed structural aspects of language is rarely described in the literature. Some authors (Silleresi et al., 2020) within the verbal part of the spectrum identify another profile made up of people with above-average intellectual abilities and developed structural aspects of language. Only the main subcategories are listed here, and within each of them there are numerous variations in the degree of development of phonological, morphosyntactic, pragmatic and intellectual abilities. When this is joined by differences in the degree of manifestation of stereotypical behavior, sensory sensitivity, comorbid states and numerous other factors, it is clear why we are talking about the spectrum of disorders.

The onset of behavioral signs of ASD can occur in three ways. There are children who have already shown some forms of autistic behavior in the first year of life. The second, regressive type of autism, refers to children in whom, after a period of typical development, there is a loss of developed social communication skills and the emergence of stereotypes. Recent research shows that regressive onset occurs much more often than previously thought. The third, less frequently described pattern refers to children who stagnated after a period of typical development, so that they did not progress in the expected way (Ozonoff, & Iosif, 2019).

Within the autism spectrum, there are many more males than females. This ratio is usually considered to be 4-5: 1. One of the possible explanations is the existence of the so-called female protective factor, which implies that females require a much higher degree of genetic burden and/or the action of other risk factors for autism to manifest. However, the actual relationship could be somewhat different. Modern studies conducted in the Nordic countries show that the ratio of men and women with autism is actually 2-3: 1. It is believed that there are more females with autism than was previously thought, but that they are diagnosed late, both because of specific clinical manifestations and because of the tendency to camouflage. Compared to school-age boys from the autism spectrum, girls of the same age better integrate verbal and nonverbal behavior, have better imagination, initiate and maintain reciprocal conversation and make friendships more easily, but have great difficulty retaining them. In minimally verbal persons with autism, no significant gender differences in social communication and interactions, stereotypes, cognitive and adaptive functioning were observed. However, women with high-functioning autism have, as a rule, fewer stereotypes than men, and it is possible that they differ according to the form of stereotypical activities. Compared to men, they have more sensory problems, and the occurrence of compulsions and self-harm is more common (Lai et al., 2017; Lai, & Szatmari, 2020). High-functioning people with autism sometimes resort to camouflage (covering up symptoms) in order to fit in with society. Women tend to mask symptoms and do so in a variety of ways: making eye contact, using learned and prepared phrases, mimicking other people's behavior, including facial expression, taking care of appropriate spatial distance during conversation, and the appropriateness of topics. Because camouflage requires enormous cognitive effort, they are exposed to greater stress, anxiety, and depressive reactions (Lai et al., 2017).

Within the autism spectrum, there is a huge heterogeneity in relation to the share of genetic factors in the development of autism, clinical picture, outcomes and prognosis. The etiology of autism is very complex and is influenced by numerous factors. In most cases, autism cannot be reported in connection with any condition of known etiology, and then we talk about idiopathic autism. We use the term syndromic autism when autism is associated with a condition of known etiology, such as a fragile X chromosome, tuberous sclerosis, or Down syndrome. The risk that a brother or sister of a child with idiopathic autism will have autism itself ranges from 3% to 10%, and if a broader autistic phenotype is observed, then the risk rises to more than 18% (Ozonoff et al., 2011). Genetic testing does not indicate a unique pattern of inheritance in autism. While in some cases autism is accompanied by monogenic conditions, various forms of polygenic inheritance are also registered. Research also indicates a certain role of de novo mutations, as well as the possible significance of epigenetic factors. Epigenetic mechanisms are biochemical modifications of DNA or histones that do not alter DNA sequences, but only affect gene expression. Different etiological factors can cause the appearance of the same or similar phenotypic manifestations (Hervás, 2016).

5. CO-OCCURRING CONDITIONS

Autism can occur in conjunction with other disorders, in which case we are talking about comorbidity. It is estimated that more than 60% of people with autism have at least one associated psychiatric condition, and many people with autism also have physical health problems (Rosen et al., 2021). The occurrence of comorbidities is associated with a poorer outcome and prognosis, higher needs for medical support, reduced level of social well-being, and in some cases with a higher mortality rate. Behavioral changes, and even some forms of aggressive and autoaggressive behavior, may indicate certain comorbid conditions. The most occuring medical conditions include gastrointestinal problems, seizures, and sleep problems, and all of these conditions can significantly worsen behavioral symptoms. These conditions are often not recognized because behavioral changes are attributed to autism itself or to the influence of some environmental, especially sensory, factors (Casanova et al., 2020). These authors believe that the possibility of concealed comorbidity should be suspected if:

• functional analysis of behavior cannot determine the exact reason for the occurrence of self-harm, heteroaggression and other forms of maladaptive behavior;

• the person with autism regressed in relation to the previous level of functioning (especially after the third year of life); 

• a person with autism does not respond well to treatment and support provided;

•  there is a history of perinatal complications, frequent visits to the emergency room, taking a variety of medications, including those not available on prescription.

In case of suspicion of a comorbid condition, it is necessary to first conduct a review of the system (a list of questions arranged by the organ system, design to uncover dysfunction and disease within that area), and then, if necessary, refer a person with autism to a specialist of a particular profile.

Autism can occur in combination with other neurodevelopmental disorders such as intellectual disability, ADHD, developmental coordination disorder, etc. ASD can be accompanied by any level of intellectual functioning, although in the last few decades, people with high-functioning autism, who often remained unrecognized in the past, are being better diagnosed. People with intellectual disabilities can have only some traits of autism, and the diagnosis is made if all diagnostic criteria are met and if deficits in the field of social communication are significantly higher than the level that would be expected in relation to the degree of cognitive functioning (APA, 2013). Autism and ADHD are neurobiological disorders with similar underlying neuropsychological deficits. Until the publication of DSM-5 (APA, 2013), these two disorders were mutually exclusive. However, everyday experience and numerous research papers have indicated a large overlap of symptomatology, as well as the possibility of coexistence of these two disorders. The prevalence of ADHD in people with autism varies in a wide range from 17% to as much as 78%, depending on the research sample and the applied research methodology. A quantitative synthesis of 18 research studies found that the prevalence of ADHD and adults with autism was 25.7% (Lugo-Marín et al., 2019). People with comorbid autism and ADHD typically have more severe symptoms, especially in the social domain, as well as a greater tendency for repetitive activities (Rosen et al., 2021). In the school context, it is important to pay attention to the fact that children with autism and ADHD are at high risk of bullying. Although it has long been known that children with autism have atypical motor development, there is a relatively small number of studies that deal with the diagnosis of comorbid developmental coordination disorder in people with autism. In a recent study, it was found that over 90% of respondents with ASD met criteria for co-occurring developmental coordination disorder (Miller et al., 2021).

As already mentioned, autism can be associated with various syndromes. The combination of autism, syndrome, and intellectual disability alters the behavioral phenotype, which significantly affects the accuracy of diagnosis. Although most people with Fragile X chromosome meet the DSM-5 criteria for autism in the area of stereotyped forms of activity, slightly less than 30% of men and only 13% of women with Fragile X meet the same criteria in the area of social communication. The situation is quite the opposite in Phelan-McDermid syndrome where most respondents have more significant deficits in the area of social communication than in the area of stereotypical behavior (Oberman, & Kaufmann, 2020). The prevalence of autism in samples of children with Down syndrome ranges from 16% to as much as 42%. Children with this form of syndrome autism have, as a rule, fewer difficulties in the field of social communication than children with idiopathic autism (Godfrey et al., 2019). Detection of an associated genetic disorder is important for several reasons: better understanding of atypical behavioral manifestations and adaptation of support services; recognition of diseases and conditions characteristic of certain syndromes and their treatment; genetic family counselling.

Although epilepsy, as the most common comorbid, neurological disease, can sometimes be associated with a syndromic condition, in many cases the etiology of epilepsy in people with autism is not entirely clear. Epilepsy is especially common in people with autism and intellectual disabilities. Studies show that some other neurological conditions are more common in people with autism than in neurotypical subjects: macrocephaly, cerebral palsy, migraine / headache, etc. (for the review see Pan et al., 2020). The associated neurological disorder can have a significant impact on the further developmental course, both directly and through the adverse effects of the drugs used. Therefore, “neurological check-ups are indicated in autism to ensure adequate physical health care and support” (Pan et al., 2020).

In addition to neurological, people with autism can have a number of psychiatric conditions. It is estimated that about 70% of people with autism have a comorbid psychiatric condition. In addition to the ADHD already described, the most common comorbid conditions are anxiety and mood disorders. Depression may be related to ongoing bullying and environmental changes. Research on samples of children and adolescents with autism shows that additional psychiatric condition has a negative impact on adaptive functioning, nutrition and sleep, as well as being able to increase social isolation, anxiety, irritability, aggression and self-harm. Supportive school services should be the main source of support for children with autism and comorbid psychiatric conditions, while ensuring cooperation with family and psychiatric services.

With the exception of ADHD, the most common psychiatric disorders in adults with autism are mood disorders (depression and bipolar disorder), as well as anxiety disorders (social anxiety disorder, obsessive-compulsive disorder, adjustment disorder, agoraphobia, panic disorder, generalized anxiety disorder), with a prevalence of about 18%. Rare studies of anxiety at different stages of the life cycle show that anxiety usually occurs in early childhood, reaching a maximum in late childhood and adolescence, and then declining in younger adulthood, only to rise again in the elderly with autism. In adults with autism, the pooled prevalence of schizophrenia spectrum disorders is 11.8% (schizophrenia is the most common in this category while other schizophrenia spectrum disorders are extremely rare), and personality disorders have a similar prevalence. Other psychiatric disorders are significantly rarer (for the review see Lugo-Marín et al., 2019). Psychiatric comorbidity requires close cooperation between the psychiatric service, parents and teachers, because the intervention is not limited to taking medication, but also to monitoring the condition, providing individualized support and removing social barriers and stigma that is often associated with psychiatric illness.

Eating and sleeping problems are relatively common in people with autism. If they occur, it is necessary to determine the real cause of the problem and create an individual intervention plan. In addition to pharmacological agents, there are a number of evidence-based strategies used to overcome these problems.

6. DEVELOPMENTAL CHANGES

Properly diagnosed autism in early childhood is generally stable, but numerous changes in the clinical presentation of autism are observed. In general, children progress somewhat more in the field of social communication, than in the area of stereotypical and repetitive behavior. After the diagnosis is made, the greatest attention is paid to the early intervention, which is focused on the family and which has the most effect if the treatment fits into the daily routines. Therefore, parental support should be provided in childhood, both formal (professional support provided by early interventionists, special education teachers, pediatricians, speech and language therapists, etc.) and informal (support provided by family and friends).

Changes in the key symptoms of autism during adolescence are highly variable. While some people with autism have made progress in social skills and communication, some adolescents with ASD may experience 1-2 year periods of aggravation of behavioral symptoms (e.g., aggression, hyperactivity, insistence on sameness). Support needs during adolescence include:

• Education – adapting space, materials, approaches and, if necessary, educational outcomes. School-age children should be provided with access to education with appropriate support and adjustment through the creation of an individual educational program (IEP). Support should not be limited to the acquisition of school knowledge, but should also be focused on peer relationships, bullying prevention, and quality leisure time and community life.

• Transitional planning refers to the transition from one school to another, from one cycle of education to the next, or to the completion of schooling and the transition to the world of adults. Individual transition plans are separate documents in some countries, while legal regulations in some countries specify them as an integral part of the IEP. Transitional goals and services need to be defined for each student that will enable those goals to be achieved.

• Sexuality – informal and formal sexual education. 

• Health-care issues – medical and behavioral support needs.

Lifespan changes are highly variable across studies and individuals. Although it happens that some people with autism progress into adulthood, some of them show persistent or even worsening symptoms. Adult support refers to housing, employment, health-care needs, and long-term care challenges.

7. REFERENCES

AlKhateeb, M., & AlDhalaan, H. (2020). Review in Autism and Epilepsy. In Epilepsy. IntechOpen. 

American Psychiatric Association (APA). (2013). Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5). American Psychiatric Publishing. 

Carpenter, K. L., Hahemi, J., Campbell, K., Lippmann, S. J., Baker, J. P., Egger, H. L., ... & Dawson, G. (2021). Digital behavioral phenotyping detects atypical pattern of facial expression in toddlers with autism. Autism Research, 14(3), 488-499. 

Casanova, M. F., Frye, R. E., Gillberg, C., & Casanova, E. L. (2020). Comorbidity and Autism Spectrum Disorder. Frontiers in Psychiatry, 11, 1273. 

Crespi, B. (2021). Pattern Unifies Autism. Frontiers in Psychiatry, 12, 59. 

Dizitzer, Y., Meiri, G., Flusser, H., Michaelovski, A., Dinstein, I., & Menashe, I. (2020). Comorbidity and health services' usage in children with autism spectrum disorder: a nested case–control study. Epidemiology and Psychiatric Sciences, 29. 

Glumbić, N. (2009). Odrasle osobe sa autizmom. FASPER. 

Godfrey, M., Hepburn, S., Fidler, D. J., Tapera, T., Zhang, F., Rosenberg, C. R., & Lee, N. R. (2019). Autism spectrum disorder (ASD) symptom profiles of children with comorbid Down syndrome (DS) and ASD: A comparison with children with DS-only and ASD-only. Research in Developmental Disabilities, 89, 83-93. 

Hawks, Z. W., & Constantino, J. N. (2020). Neuropsychiatric “Comorbidity” as Causal Influence in Autism. 

Hervás, A. (2016). Un autismo, varios autismos. Variabilidad fenotípica en los trastornos del espectro autista. Revista de Neurologia, 62(Suppl. 1), s9-s14. 

Lai, M. C., & Szatmari, P. (2020). Sex and gender impacts on the behavioural presentation and recognition of autism. Current Opinion in Psychiatry, 33(2), 117-123. 

Lai, M. C., Lombardo, M. V., Ruigrok, A. N., Chakrabarti, B., Auyeung, B., Szatmari, P., ... & MRC AIMS Consortium. (2017). Quantifying and exploring camouflaging in men and women with autism. Autism, 21(6), 690-702. 

Lecheler, M., Lasser, J., Vaughan, P. W., Leal, J., Ordetx, K., & Bischofberger, M. (2021). A matter of perspective: An exploratory study of a theory of mind autism intervention for adolescents. Psychological reports, 124(1), 39-53.

Loucas, T., Charman, T., Pickles, A., Simonoff, E., Chandler, S., Meldrum, D., & Baird, G. (2008). Autistic symptomatology and language ability in autism spectrum disorder and specific language impairment. Journal of Child Psychology and Psychiatry, 49(11), 1184-1192. 

Lugo-Marín, J., Magán-Maganto, M., Rivero-Santana, A., Cuellar-Pompa, L., Alviani, M., Jenaro-Rio, C., ... & Canal-Bedia, R. (2019). Prevalence of psychiatric disorders in adults with autism spectrum disorder: A systematic review and meta-analysis. Research in Autism Spectrum Disorders, 59, 22-33. 

Mannion, A., & Leader, G. (2013). Comorbidity in autism spectrum disorder: A literature review. Research in Autism Spectrum Disorders, 7(12), 1595-1616. 

Melo, C., Ruano, L., Jorge, J., Pinto Ribeiro, T., Oliveira, G., Azevedo, L., & Temudo, T. (2020). Prevalence and determinants of motor stereotypies in autism spectrum disorder: A systematic review and meta-analysis. Autism, 24(3), 569-590. 

Miller, H. L., Sherrod, G. M., Mauk, J. E., Fears, N. E., Hynan, L. S., & Tamplain, P. M. (2021). Shared Features or Co-occurrence? Evaluating Symptoms of Developmental Coordination Disorder in Children and Adolescents with Autism Spectrum Disorder. Journal of Autism and Developmental Disorders, 1-13. 

Oberman, L. M., & Kaufmann, W. E. (2020). Autism Spectrum Disorder versus Autism Spectrum Disorders: Terminology, concepts, and clinical practice. Frontiers in Psychiatry, 11, 484. 

Ozonoff, S., & Iosif, A. M. (2019). Changing conceptualizations of regression: What prospective studies reveal about the onset of autism spectrum disorder. Neuroscience & Biobehavioral Reviews, 100, 296-304. 

Ozonoff, S., Young, G. S., Carter, A., Messinger, D., Yirmiya, N., Zwaigenbaum, L., ... & Stone, W. L. (2011). Recurrence risk for autism spectrum disorders: a Baby Siblings Research Consortium study. Pediatrics, 128(3), e488-e495. 

Pan, P. Y., Bölte, S., Kaur, P., Jamil, S., & Jonsson, U. (2020). Neurological disorders in autism: A systematic review and meta-analysis. Autism, 1362361320951370. 

Rosen, N. E., Lord, C., & Volkmar, F. R. (2021). The Diagnosis of Autism: From Kanner to DSM-III to DSM-5 and Beyond. Journal of Autism and Developmental Disorders, 1-18. 

Russell, K. M., Frost, K. M., & Ingersoll, B. (2019). The relationship between subtypes of repetitive behaviors and anxiety in children with autism spectrum disorder. Research in Autism Spectrum Disorders, 62, 48-54. 

Silleresi, S., Prevost, P., Zebib, R., Bonnet‐Brilhault, F., Conte, D., & Tuller, L. (2020). Identifying language and cognitive profiles in children with ASD via a cluster analysis exploration: Implications for the new ICD‐11. Autism Research, 13(7), 1155-1167. 

WHO (2018). ICD-11. Retrieved from https://icd.who.int/browse11/l-m/en