Autism is a severe disruption of the normal development process and is often diagnosed within the first few years of life. Autism is viewed as a spectrum or a continuum of disorders, with varying degrees of severity and levels of functioning. The term Autism Spectrum Disorder (ASD) is frequently used interchangeably with autism. Diagnoses from DSM-IV such as Asperger’s Syndrome, Childhood Disintegrative Disorder, Pervasive Developmental Disorder, Autistic Disorder and Pervasive Developmental Disorders (Not Otherwise Specified) are now all included within the umbrella of ASD under DSM-5.
DSM-5 – Autism Spectrum Disorder
The fifth version of the Diagnostic and Statistical Manual (DSM-5) was published in 2013. The manual reflects the state of knowledge of mental and emotional disorders. Changes in the newest edition include combining the previously distinct Pervasive Developmental Disorders (Autistic Disorder, Asperger’s Disorder, and Pervasive Developmental Disorder – Not Otherwise Specified) into one new disorder: Autism Spectrum Disorder.
However, due to changes in criteria, not all people diagnosed with a Pervasive Developmental Disorder in the previous edition of the DSM will receive a diagnosis of Autism Spectrum Disorder in the new criteria. In addition to the changes in criteria, a 3-level severity scale has been added to the manual. Those who no longer meet the diagnostic criteria may qualify for Social Communication Disorder.
Causes
At this point, the cause of autism remains unknown, however, the one theory that has strong scientific evidence is that genetics play a significant role in contributing to the occurrence of ASD. Studies show the concordance rate for identical twins is much higher than for fraternal twins, and ongoing research is beginning to identify genes that may put an individual at risk.
Additionally, in the last decade, there are more postulations on the relationship between environmental toxins, diets, vaccines and autism, but up till now, there is no convincing scientific evidence that demonstrate a causal link between ASD and these toxins, life-saving vaccines or diets. As a result, adherence to these speculative beliefs is tragic because more children are harmed by not receiving life-saving vaccination.
Finding the answer will require long-term, painstaking, rigorous, and sophisticated scientific investigation. Professional responsibility and ethics demand that care be taken not to over-speculate, misrepresent nor present mere hypotheses as facts for the causes of autism.
Prevalence
- 1 in 54 children has been identified with autism spectrum disorder (ASD) in the United States, 10 percent higher than the reported statistic in 2016 of 1 in 59 children (Center for Diseases Prevention and Control, CDC 2020)
- 1,100,000 cases of autism in China; 650,000 in the UK; 500,000 in the Philippines; and 180,000 in Thailand (the World Health Organization, WHO, 2009)
- 49 children in every 10,000 is diagnosed with the disorder in Hong Kong (epidemiological study by V. Wong & S. Hui (2007) of The University of Hong Kong)
- ASD is more than 4 times more common among boys than among girls. Per 1,000 children with ASD aged 8 years, around 30 are male while around 7 are female. (Centers for Disease Control and Prevention, CDC, ASD)
- Studies in Asia, Europe, and North America have identified individuals with ASD with an average prevalence of about 1%. A study in South Korea reported a prevalence of 2.6%. (Centers for Disease Control and Prevention, CDC, ASD)
- Approximately 67 million people worldwide are affected by autism.
It is generally believed that the prevalence is similar across countries and cultures, although the numbers obtained in prevalence studies vary according to the methodology and diagnostic criteria used.
Boys are affected by autism at a much higher rate than girls, for reasons that are not entirely clear. A similar pattern is seen in other childhood disorders such as Attention Deficit Disorder.