Autism Facts

Globally, autism is estimated to affect 24.8 million people as of 2015. As of 2010, the number of people affected is estimated at about 1–2 per 1,000 worldwide. It occurs four to five times more often in boys than girls. About 1.5% of children in the United States (one in 68) are diagnosed with ASD as of 2014, a 30% increase from one in 88 in 2012.The rate of autism among adults aged 18 years and over in the United Kingdom is 1.1%. The number of people diagnosed has been increasing dramatically since the 1980s, partly due to changes in diagnostic practice; the question of whether actual rates have increased is unresolved.

Most recent reviews tend to estimate a prevalence of 1–2 per 1,000 for autism and close to 6 per 1,000 for ASD, and 11 per 1,000 children in the United States for ASD as of 2008; because of inadequate data, these numbers may underestimate ASD’s true rate. Globally, autism affects an estimated 24.8 million people as of 2015, while Asperger syndrome affects a further 37.2 million. In 2012, the NHS estimated that the overall prevalence of autism among adults aged 18 years and over in the UK was 1.1%. Rates of PDD-NOS’s has been estimated at 3.7 per 1,000, Asperger syndrome at roughly 0.6 per 1,000, and childhood disintegrative disorder at 0.02 per 1,000. CDC’s most recent estimate is that 1 out of every 68 children, or 14.7 per 1,000, has an ASD as of 2010.

The number of reported cases of autism increased dramatically in the 1990s and early 2000s. This increase is largely attributable to changes in diagnostic practices, referral patterns, availability of services, age at diagnosis, and public awareness,] though unidentified environmental risk factors cannot be ruled out.The available evidence does not rule out the possibility that autism’s true prevalence has increased; a real increase would suggest directing more attention and funding toward changing environmental factors instead of continuing to focus on genetics.

Boys are at higher risk for ASD than girls. The sex ratio averages 4.3:1 and is greatly modified by cognitive impairment: it may be close to 2:1 with intellectual disability and more than 5.5:1 without.Several theories about the higher prevalence in males have been investigated, but the cause of the difference is unconfirmed;one theory is that females are underdiagnosed.[

Although the evidence does not implicate any single pregnancy-related risk factor as a cause of autism, the risk of autism is associated with advanced age in either parent, and with diabetes, bleeding, and use of psychiatric drugs in the mother during pregnancy.The risk is greater with older fathers than with older mothers; two potential explanations are the known increase in mutation burden in older sperm, and the hypothesis that men marry later if they carry genetic liability and show some signs of autism.Most professionals believe that race, ethnicity, and socioeconomic background do not affect the occurrence of autism.

Autism Facts:

  • Autism prevalence figures are growing
  • More children will be diagnosed with autism this year than with AIDS, diabetes & cancer combined
  • ASD is estimated to affect more than 3 million individuals in the U.S.
  • Autism is the fastest-growing serious developmental disability in the U.S.
  • Boys are four times more likely than girls to have autism
  • The increase in prevalence rate cannot be explained by better diagnosis alone. Some have suggested that autism is just being better diagnosed today versus years ago and that many cases of intellectual disability are now being coded as autism. This would also assume that the experts diagnosing autism before did not know what they were doing. This is NOT TRUE. Autism is the only disorder dramatically on the rise while mental retardation or intellectual disability, Down syndrome and cystic fibrosis remain relatively the same.