Autism Spectrum Disorder (ASD) Facts

What is autism spectrum disorder?

Autism spectrum disorder (ASD) is a developmental disability that can cause significant social, communication, and behavioral challenges. There is often nothing about how people with ASD look that sets them apart from other people, but people with ASD may communicate, interact, behave, and learn in ways that are different from most other people. The learning, thinking, and problem-solving abilities of people with ASD can range from gifted to severely challenged. Some people with ASD need a lot of help in their daily lives; others need less.

A diagnosis of ASD now includes several conditions that used to be diagnosed separately: autistic disorder, pervasive developmental disorder not otherwise specified (PDD-NOS), and Asperger syndrome. These conditions are now all called autism spectrum disorder.

Signs and Symptoms

People with ASD often have problems with social, emotional, and communication skills. They might repeat certain behaviors and might not want change in their daily activities. Many people with ASD also have different ways of learning, paying attention, or reacting to things. Signs of ASD begin during early childhood and typically last throughout a person's life.

Children or adults with ASD might

• Not point at objects to show interest (e.g. not point at an airplane flying over)
• Not look at objects when another person points at them
• Have trouble relating to others or not have an interest in other people at all
• Avoid eye contact and want to be alone
• Have trouble understanding other people's feelings or talking about their own feelings
• Prefer not to be held or cuddled, or might cuddle only when they want to
• Appear to be unaware when people talk to them, but respond to other sounds
• Be very interested in people, but not know how to talk, play, or relate to them
• Repeat or echo words or phrases said to them, or repeat words or phrases in place of normal language
• Have trouble expressing their needs using typical words or motions
• Not play "pretend" games (e.g. not pretend to "feed" a doll)
• Repeat actions over and over again
• Have trouble adapting when a routine changes
• Have atypical reactions to the way things smell, taste, look, feel, or sound
• Lose skills they once had (e.g. stop saying words they were using)

Diagnosis

Diagnosing ASD can be difficult since there is no medical test, like a blood test, to diagnose the disorders. Doctors look at the child's behavior and development to make a diagnosis.

ASD can sometimes be detected at age 18 months or younger. By age two, a diagnosis by an experienced professional can be considered very reliable.¹ However, many children do not receive a final diagnosis until they're much older. This delay means that children with ASD might not get the early help they need.

Treatment

There is currently no cure for ASD. However, research shows that early intervention treatment services can improve a child's development.^2,3 Early intervention services help children from birth to three years old (36 months) learn important skills. Services can include therapy to help the child talk, walk, and interact with others. Therefore, it is important to talk to your child's doctor as soon as possible if you think your child has ASD or another developmental problem.

Even if your child has not been diagnosed with an ASD, they may be eligible for early intervention treatment services. The Individuals with Disabilities Education Act (IDEA) says that children under the age of three years (36 months) who are at risk of having developmental delays may be eligible for services. These services are provided through an early intervention system in your state. Through this system, you can ask for an evaluation.

In addition, treatment for particular symptoms, such as speech therapy for language delays, often does not need to wait for a formal ASD diagnosis.

Causes and Risk Factors

All of the causes of ASD are not known. However, scientists have learned that there are likely many causes for multiple types of ASD. There may be many different factors that make a child more likely to have an ASD, including environmental, biologic, and genetic factors:

• Most scientists agree that genes are one of the risk factors that can make a person more likely to develop ASD.^4,5
• Children who have a sibling with ASD are at a higher risk of also having ASD.^6–11
• Individuals with certain genetic or chromosomal conditions, such as fragile X syndrome or tuberous sclerosis, can have a greater chance of having ASD.^12–16
• When taken during pregnancy, the prescription drugs valproic acid and thalidomide have been linked with a higher risk of ASD.^17,18
• There is some evidence that the critical period for developing ASD occurs before, during, and immediately after birth.¹⁹
• Children born to older parents are at a greater risk for having ASD.²⁰

Who is affected?

ASD occurs in all racial, ethnic, and socioeconomic groups, but it is about four times more common among boys than girls.

If You're Concerned

If you think your child might have ASD or you think there could be a problem with the way your child plays, learns, speaks, or acts, contact your child's doctor, and share your concerns.

If you or the doctor is still concerned, ask the doctor for a referral to a specialist who can do a more in-depth evaluation of your child. Specialists who can do a more in-depth evaluation and make a diagnosis include

• Developmental pediatricians (doctors who have special training in child development and children with special needs)
• Child neurologists (doctors who work on the brain, spine, and nerves)
• Child psychologists or psychiatrists (doctors who know about the human mind)

At the same time, call your state's public early childhood system to request a free evaluation to find out if your child qualifies for intervention services. This is sometimes called a Child Find evaluation. You do not need to wait for a doctor's referral or a medical diagnosis to make this call.

Where to call for a free evaluation from the state depends on your child's age:

• If your child is not yet three years old, contact your local early intervention system. You can find the right contact information for your state by calling the Early Childhood Technical Assistance Center (ECTA) at 919-962-2001, or visit the ECTA website (Link opens in a new windowhttps://ectacenter.org/contact/ptccoord.asp).
• If your child is three years old or older, contact your local public school system:
  • Even if your child is not yet old enough for kindergarten or enrolled in a public school, call your local elementary school or board of education, and ask to speak with someone who can help you have your child evaluated.
  • If you're not sure who to contact, call the ECTA at 919-962-2001, or visit the ECTA website (Link opens in a new windowhttps://ectacenter.org/contact/ptccoord.asp).

Research shows that early intervention services can greatly improve a child's development.^2,3 In order to make sure your child reaches their full potential, it is very important to get help for an ASD as soon as possible.

Economic Costs

• The total costs per year for children with ASD in the United States were estimated to be between $11.5 billion and $60.9 billion (2011 U.S. dollars). This significant economic burden represents a variety of direct and in-direct costs, from medical care to special education to lost parental productivity.^21,22
• Children and adolescents with ASD had average medical expenditures that exceeded those without ASD by $4,110 to $6,200 per year. On average, medical expenditures for children and adolescents with ASD were 4.1 to 6.2 times greater than for those without ASD. Differences in median expenditures ranged from $2,240 to $3,360 per year with median expenditures 8.4 to 9.5 times greater.²³
• In 2005, the average annual medical costs for Medicaid-enrolled children with ASD were $10,709 per child, which was about six times higher than costs for children without ASD ($1,812).²⁴
• In addition to medical costs, intensive behavioral interventions for children with ASD cost from $40,000 to $60,000 per child per year.²⁵

Vaccine Safety

Some people have had concerns that ASD might be linked to the vaccines children receive, but studies have shown that there is no link between receiving vaccines and developing ASD.

References

1. Lord, C., Risi, S., DiLavore, P.S., Shulman, C., Thurm, A., & Pickles, A. (2006, June). Autism from 2 to 9 years of age. Archives of General Psychiatry, 63(6), 694–701.
2. Handleman, J.S., & Harris, S. (Eds.). Preschool education programs for children with autism (2nd ed). Austin, TX: Pro-Ed. 2000.
3. National Research Council. (2001). Educating children with autism. Washington, DC: National Academy Press.
4. Huquet, G., Ey, E., & Bourgeron, T. (2013). The genetic landscapes of autism spectrum disorders. Annual Review of Genomics and Human Genetics, 14, 191–213.
5. Bai, D., Yip, B.H.K., Windham, G.C., Sourander, A., Francis, R., Yoffe, R., et al. (2019, July 17). Association of genetic and environmental factors with autism in a 5-country cohort. Journal of the American Medical Association (JAMA) Psychiatry, 76(10), 1035–1043. doi: 10.1001/jamapsychiatry.2019.1411
6. Rosenberg, R.E., Law, J.K., Yenokyan, G., McGready, J., Kaufmann, W.E., & Law, P.A. (2009). Characterisitics and concordance of autism spectrum disorders among 277 twin pairs. Archives of Pediatrics and Adolescent Medicine, 163(10), 907–914.
7. Hallmayer, J., Cleveland, S., Torres, A., Phillips, J., Cohen, B., Torigoe, T., et al. (2011). Genetic heritability and shared environmental factors among twin pairs with autism. Archives of General Psychiatry, 68(11), 1095–1102.
8. Ronald, A., Happe, F., Bolton, P., Butcher, L.M., Price, T.S., Wheelwright, S., et al. (2006). Genetic heterogeneity between the three components of the autism spectrum: A twin study. Journal of the American Academy of Child and Adolescent Psychiatry, 45(6), 691–699.
9. Taniai, H., Nishiyama, T., Miyahci, T., Imaeda, M., & Sumi, S. (2008). Genetic influences on the board spectrum of autism: Study of proband-ascertained twins. American Journal of Medical Genetics, 147B(6), 844–849.
10. Ozonoff, S., Young, G.S., Carter, A., Messinger, D., Yirmiya, N., Zwaigenbaum, L., et al. (2011). Recurrence risk for autism spectrum disorders: A Baby Siblings Research Consortium study. Pediatrics, 128, e488–e495.
11. Sumi, S., Taniai, H., Miyachi, T., & Tanemura, M. (2006). Sibling risk of pervasive developmental disorder estimated by means of an epidemiologic survey in Nagoya, Japan. Journal of Human Genetics, 51, 518–522.
12. DiGuiseppi, C., Hepburn, S., Davis, J.M., Fidler, D.J., Hartway, S., Lee, N.R., et al. (2010). Screening for autism spectrum disorders in children with Down syndrome. Journal of Developmental & Behavioral Pediatrics, 31, 181–191.
13. Cohen, D., Pichard, N., Tordjman, S., Baumann, C., Burglen, L., Excoffier, E., et al. (2005). Specific genetic disorders and autism: Clinical contribution towards their identification. Journal of Autism and Developmental Disorders, 35(1), 103–116.
14. Hall, S.S., Lightbody, A.A., & Reiss, A.L. (2008). Compulsive, self-injurious, and autistic behavior in children and adolescents with fragile X syndrome. American Journal of Mental Retardation, 113(1), 44–53.
15. Zecavati, N., & Spence, S.J. (2009). Neurometabolic disorders and dysfunction in autism spectrum disorders. Current Neurology and Neuroscience Reports, 9(2), 129–136.
16. Sztainberg, Y., & Zoghbi, H.Y. (2016, October 26). Lessons learned from studying syndromic autism spectrum disorders. Nature Neuroscience, 19(11), 1408–1417. doi: 10.1038/nn.4420
17. Christensen, J., Grønborg, T.K., Sørensen, M.J., Schendel, D., Parner, E.T., Pedersen, L.H., et al. (2013). Prenatal valproate exposure and risk of autism spectrum disorders and childhood autism. JAMA, 309(16), 1696–1703.
18. Strömland, K., Nordin, V., Miller, M., Akerström, B., & Gillberg, C. (1994). Autism in thalidomide embryopathy: A population study. Developmental Medicine & Child Neurology, 36(4), 351–356.
19. Gardener, H., Spiegelman, D., & Buka, S.L. (2011). Perinatal and neonatal risk factors for autism: A comprehensive meta-analysis. Pediatrics, 128(2), 344–355.
20. Durkin, M.S., Maenner, M.J., Newschaffer, C.J., Lee, L.C., Cunniff, C.M., Daniels, J.L., et al. (2008). Advanced parental age and the risk of autism spectrum disorder. American Journal of Epidemiology, 168(11), 1268–1276.
21. Lavelle, T.A., Weinstein, M.C., Newhouse, J.P., Munir, K., Kuhlthau, K.A., & Prosser, L.A. (2014, February 10). Economic burden of childhood autism spectrum disorders. Pediatrics, 133(3), e520–529. doi: 10.1542/peds.2013-0763
22. Buescher, A.V.S., Cidav, Z., Knapp, M., & Mandell, D.S. (2014, August). Costs of autism spectrum disorders in the United Kingdom and the United States. JAMA Pediatrics, 168(8), 721–728. doi: 10.1001/jamapediatrics.2014.210
23. Shimabukuro, T.T., Grosse, S.D., & Rice, C. (2008, March). Medical expenditures for children with an autism spectrum disorder in a privately insured population. Journal of Autism and Developmental Disorders, 38(3), 546–552. doi: 10.1007/s10803-007-0424-y
24. U.S. Centers for Disease Control and Prevention (CDC). (Reviewed 2020, September 25). Autism spectrum disorder (ASD): Prevalence. Retrieved November 5, 2021, from https://www.cdc.gov/ncbddd/autism/data.html
25. Amendah, D., Grosse, S.D., Peacock, G., & Mandell, D.S. (2011). The economic costs of autism: A review. In D. Amaral, D. Geschwind, & G. Dawson (Eds.), Autism spectrum disorders (pp. 1347–1360). Oxford: Oxford University Press.