ASD prevalence in kids continues to increase

April 3, 2014

As of 2010, 1 in every 68 children aged 8 years had autism spectrum disorder (ASD), according to new data from the Centers for Disease Control and Prevention (CDC). This is up from 1 in 88 in 2008; 1 in 110 in 2006; and it’s up 123% from 2002 when 1 in every 150 children aged 8 years was diagnosed with ASD.

 

As of 2010, 1 in every 68 children aged 8 years had autism spectrum disorder (ASD), according to new data from the Centers for Disease Control and Prevention (CDC). This is up from 1 in 88 in 2008; 1 in 110 in 2006; and it’s up 123% from 2002 when 1 in every 150 children aged 8 years was diagnosed with ASD.

Whether true incidence is really increasing that quickly or whether some or all of the increase can be explained by things such as differing diagnostic practices, disparities in healthcare access, increased awareness, or countless other possibilities, remains uncertain.

The CDC used the Autism and Developmental Disabilities Monitoring Network to report on findings from 11 US sites for the 2010 surveillance year.

The researchers found the overall prevalence of ASD to be 14.7 per 1000 children aged 8 years, but prevalence ranged widely, from a low of 5.7 per 1000 in Alabama to a high of 21.9 per 1000 in New Jersey. After New Jersey, the highest prevalence rates were in Utah (18.6) and North Carolina (17.3).

Prevalence also continued to differ tremendously by gender, with boys about 4.5 times as likely to be affected as girls (1 in 42 boys vs 1 in 189 girls). Non-Hispanic white children were about 30% more likely to have ASD than non-Hispanic black children and about 50% more likely than Hispanic children.

As prevalence has risen, so has the percentage of children with ASD who have average or above average intelligence. In 2010, almost half the children (46%) with ASD had an intelligence quotient (IQ) score above 85, up from 32% in 2002. Almost one-third (31%) had IQ scores at or below 70, and 23% had IQ scores between 71 and 85.

The researchers found a far higher prevalence (almost double) of ASD without co-occurring intellectual disability among white children than among black or Hispanic children. Median age of diagnosis has remained fairly constant over the years at 4.5 years, as has distribution of diagnostic subtype (ie, autistic disorder, ASD/pervasive development disorder, and Asperger syndrome). 


 

 

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