Autism Spectrum Disorder

'Original Editor - Kirenga Bamurange Liliane Top Contributors - Kirenga Bamurange Liliane, Lucinda hampton, Jess Bell, Kim Jackson, Naomi O'Reilly, Nupur Smit Shah and Robin Tacchetti

Introduction

Autism, referred to as Autism Spectrum Disorder (ASD), is a neurodevelopmental disorder that affects the way an individual with ASD relates to others and to their environment.

Autism traits may be evident in childhood, but some individuals will not be diagnosed until later in life. Some individuals may have significant disabilities and require ongoing care while others live independently.

Autism can affect an individual's education and employment opportunities, and may add stress to the families providing care and support.

In the video below, the neuroscience of autism along with potential factors and mechanisms involved in the development of autism are discussed (2 minutes).

Co-occurring Conditions

Individuals with ASD frequently have co-occurring conditions (eg epilepsy, depression, anxiety and attention deficit hyperactivity disorder) and other challenging behaviours (eg difficulty sleeping and self-injury). The level of intellectual functioning also varies greatly among individuals with ASD. Some may experience profound impairment whereas others have average or higher IQs.

Aetiology/Epidemiology

"ASD is a neurobiological disorder influenced by both genetic and environmental factors affecting the developing brain."

Research into the aetiological mechanisms of ASD is ongoing, but at present, no single cause for this condition has been identified.

• The reported prevalence of ASD is 1 in 68 individuals.
• Prevalence rates vary between countries.
• The general prevalence of ASD is increasing globally. However, it should be noted that this might be due to increased awareness of ASD, potential overdiagnosis, or diagnostic criteria that are over-inclusive.

Signs and Symptoms

Challenges that people with autism face might include:

• struggling to communicate their needs and desires
• having difficulty interpretating what other people mean
• their ability to process sensory and cognitive information might be impacted

Children and youth with ASD have different intellectual abilities. Individuals with ASD might have limited or no verbal communication, and very limited adaptive behaviour.

Risk Factors

The following factors have been linked to ASD:

• Hereditary factors, parental history of psychiatric disorders, pre-term births.
• Parental age ( advance maternal and paternal age)
• Maternal history of autoimmune disease such as diabetes, thyroid disease and psoriasis.
• Prenatal exposure to psychotropic drugs or insecticides like thalidomide and valproic acid.
• Some of the known genetic disorders such as fragile X, tuberous sclerosis, Down syndrome, Rett syndrome even though they represent a very small amount of overall ASD cases .
• Maternal infection or immune activation during pregnancy
• Obstetric factors like uterine bleeding, caesarian delivery, low birth weight, preterm delivery, and low Apgar scores are more consistently associated with autism.

Diagnosis

ADS advocates rebel against negative stereotypes

ASD can be diagnosed by various professionals, ideally with input from multiple disciplines.

• Diagnoses based on combined clinician observation and caregiver reports are consistently more reliable than those based on either observation or reports alone.
• Later diagnoses often occur in presence of co-occurring problems such as anxiety, hyperactivity, or mood disorders that might have triggered the ASD, along with the same factors that play a part in delayed diagnoses in younger children.
• There is a need for clinical follow-up and reassessments of children diagnosed with ASDs, especially during the preschool years.
• There are currently no clear existing ASD biomarkers or diagnostic measures. The diagnosis is made based on the completion of descriptive criteria. .

To identify early symptoms of ASDs and sometimes help make a definitive diagnosis, different approaches/tools are used in different countries. The following ones are used :

• The Modified Checklist for Autism in Toddlers, Revised (M-CHAT-R). A screener that asks a series of 20 questions about the child’s behavior. It's intended for toddlers between 16 and 30 months of age. See here
• CARS: Childhood Autism Rating Scale. The form is used with individuals of all ages and in both clinical and research settings.
• ADOS : Autism Diagnostic Observation Schedule. A standardised, semi-structured observational assessment of features relevant to the diagnosis of ASD across the lifespan.

Asperger’s syndrome is an outdated name for people who have a high-functioning form of autism spectrum disorder. There is no longer a separate diagnosis for Asperger's syndrome, although some people may prefer to keep using this term.

Treatment

ADS service dog encourages outward expression

There are lots of autism treatments, with the right ones needing to be being specific to the individual in regards to needs and challenges. Selecting the correct treatments is a collaborative affair, between health professionals, the individual and caregivers.

The more common treatments for autism include:

1. Behavioural Therapies: aim to improve specific behaviours and develop skills, and employs orthodox behaviour strategies, for example rewarding suitable behaviors and ignoring/discouraging inappropriate behaviours.
2. Occupational Therapy: concentrate on adaptive skills needed for activities of daily living (ADLs).
3. Sensory Therapy. Numerous sensory interventions have been developed to normalise various sensory-challenges including sensory, visual and auditory interventions.
4. Speech Therapy: improve the child's speech pattern and language understanding.
5. Physical Therapy: improve physical and motor skills. You can read more about the Physiotherapy Management on this page. Physiotherapy for Autism Spectrum Disorder Children With Motor Control Disabilities
6. Complementary and alternative treatments including chiropractic care, animal therapy, art therapy, music therapy, or relaxation therapies are also used as treatment options for people with ASD .
7. Medications may be are used to treat the symptoms. The following can be used if agreed upon:
   • Antipsychotic medications for repetitive behavior patterns and aggression
   • Serotonin reuptake inhibitors (SSRIs)
   • Stimulants, and other antipsychotics for problematic behaviours (like aggression) etc.

Prognosis

Autism is a lifelong condition with an extensive variety of treatments available. Early intervention gives the best results. Any ADS treatment should be sought from qualified medical professionals.

Autism Low Resource Settings

The prevalence of autism in many low and middle-income countries is unknown. Research about the ASD diagnosis process in LMICs is still limited. The mean age at ASD diagnosis was very similar across LMICs but older than in high-income countries . Studies are required, specifically, epidemiological studies, to define the magnitude of the problem of ASD in LMICs. The scarcity of these studies is due to different barriers including:

• Lack of knowledge about epidemiological research
• Need of contextualization of research tools
• Shortage of experienced health professionals
• Stigma and lack of awareness about ASDs among these professionals (health, social and educational care)

ASDs in LMICs currently face many barriers, however efforts to raise awareness about ASDs through different organizations and institutions is ongoing. There is a need for research infrastructure, funding, and capacity, and inclusive education policies. This will help with an improvement in the quality of life of people with ASD and bring their acceptance into society.

References