Autism: what is it?

Autism is a member of the group of pervasive developmental disorders (PDDs), which appear in early childhood, usually before the age of 3. Although symptoms and severity vary, all of these disorders affect a child's or adult's ability to communicate and interact with others.

The most common TEDs are:

Autism
Asperger's syndrome
Rett syndrome
Unspecified TEDs (TED-NS)
Disintegrative disorders of childhood

Causes of autism

Autism is believed to be a developmental disorder, the exact causes of which are still unknown. Researchers agree that many factors are at the origin of PDD including genetic and environmental factors, influencing the development of the brain before and after birth.

Several genes are believed to be involved in the development of autism in a child. These are thought to play a role in fetal brain development. Certain genetic predisposing factors could increase a child's risk of having autism or PDD.

Environmental factors, such as exposure to toxic substances before or after birth, complications during childbirth or infections before birth, could also be involved. In any case, the education or the behaviour of the parents towards the child is not responsible for autism.

In 1998, a British study1 attributed a link between autism and exposure to certain vaccines, in particular the vaccine against measles, rubella and mumps (MMR in France, MMR in Quebec). However, several studies have subsequently shown that there is no association between vaccination and autism.

Associated disorders

Many children with autism also suffer from other neurological disorders6, such as:

1. Epilepsy (estimated to affect 20 to 25% of children with autism18).
2. Mental retardation (estimated to affect up to 30% of children with PDD19).
3. Bourneville tuberous sclerosis (up to 3.8% of children with autism20).
4. Fragile X syndrome (up to 8.1% of children with autism20).

People with autism sometimes have:

• Problems sleeping (falling asleep or staying asleep).
• Gastrointestinal problems or allergies.
• Seizures that start in childhood or adolescence. These seizures can lead to unconsciousness, convulsions, that is, uncontrollable shaking of the whole body, or unusual movements.
• Psychiatric disorders such as anxiety (very present and related to difficulty adapting to changes, whether positive or negative), phobias and depression.
• Cognitive disorders (attention disorders, executive function disorders, memory disorders, etc.)

Living with a child suffering from autism brings about many changes in the organization of family life. Parents and siblings have to face this diagnosis and a new organization of daily life, which is not always very simple. All of this can create a lot of stress for the entire household.

Prevalence

About 6 to 7 in 1000 people have PDD in those under 20 or one in 150 children. Autism affects 2 in 1000 children under 20. One-third of children with PDD present with mental retardation Associate. (2009 data from the Haute Autorité de Santé - HAS, France)

In Quebec, PDDs affect approximately 56 in 10,000 school-age children or 1 in 178 children. (2007-2008 data, Fédération québécoise de l'Autisme)

In the United States, one in 110 children would have an autism spectrum disorder.

Over the past 20 years, the number of autism cases has increased dramatically and is now one of the most common disabilities in schools. Better diagnostic criteria, the increasingly early identification of children with PDD, as well as the awareness of professionals and the public have undoubtedly contributed to the increase in the prevalence of PDDs around the world.

Diagnosis of autism

Although signs of autism often appear around the age of 18 months, a clear diagnosis is sometimes not possible until the age of 3, when delays in language, development and social interactions are over. Obvious. The earlier the child is diagnosed, the sooner we can intervene.


To make a diagnosis of PDD, various factors must be observed in the child's behaviour, language skills and social interactions. The diagnosis of PDD is made after a multidisciplinary investigation. Numerous examinations and tests are necessary.


In North America, the standard screening tool is the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) published by the American Psychiatric Association. In Europe and elsewhere in the world, healthcare professionals generally use the International Classification of Diseases (ICD-10).


In France, there are Autism Resource Centers (ARCs) that benefit from multidisciplinary teams specializing in diagnosing autism and PDDs.