Overview

What is autism spectrum disorder (ASD), previously called autism and pervasive developmental disorders?

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by the following:

Difficulties in social communication differences, including verbal and nonverbal communication.
Deficits in social interactions.
Restricted, repetitive patterns of behavior, interests or activities and sensory problems

Many of those with ASD can have delayed or absence of language development, intellectual disabilities, poor motor coordination and attention weaknesses.

What is the difference between autism and autism spectrum disorder (ASD)?

The term autism was changed to autism spectrum disorder in 2013 by the American Psychiatric Association. ASD is now an umbrella term that covers the following conditions:

Autistic disorder.
Pervasive developmental disorder — not otherwise specified (PDD-NOS).
Asperger syndrome.

People with ASD have trouble with social interactions and with interpreting and using non-verbal and verbal communication in social contexts. Individuals with ASD may also have the following difficulties:

Inflexible interests.
Insistence on sameness in environment or routine.
Repetitive motor and sensory behaviors, like flapping arms or rocking.
Increased or decreased reactions to sensory stimuli.

How well someone with ASD can function in day-to-day life depends on the severity of their symptoms. Given that autism varies widely in severity and everyday impairment, the symptoms of some people aren’t always easily recognized.

When might you begin to wonder if your child has autism spectrum disorder (ASD)?

While ASD is believed to be a disorder of very early brain development, the behavioral signs of autism characteristics surface between age 1 and ½ years of age and 3 years of age.

How common is autism spectrum disorder (ASD)?

Based on most recent CDC report, ASD is estimated to affect about 1 in 54 children, with boys being more likely to have ASD than girls. There were more than 5 million adults in the US, or 2.21% of the population, with ASD as of 2017. Government statistics suggest that the prevalence of ASD (how common it is) has risen 10% to 17% in recent years.

Symptoms and Causes

What causes autism spectrum disorder (ASD)?

There is no clear-cut cause of ASD. Some causes that are supported by research include genetic and some environmental factors. Specific genetic causes can only be identified in 10% to 20% of cases. These cases include specific genetic syndromes associated with ASD and rare changes in the genetic code.

Risk factors include older parental age, low birth weight, prematurity and maternal use of valproic acid or thalidomide during pregnancy, among others. This field of study is an active one for research.

Are siblings at greater risk for autism spectrum disorder (ASD)?

The truth is that genetics do play a role in autism. When one child is diagnosed with ASD, the next child to come along has about a 20% greater risk of developing autism than normal. When the first two children in a family have both been diagnosed with ASD, the third child has about a 32% greater risk of developing ASD.

Do vaccines cause autism (ASD)?

Many scientifically-sound studies have proven that vaccines do not cause autism. When children suddenly show symptoms of ASD, some parents mistakenly blame a recent vaccination. No reliable study has found any proven link between childhood vaccination and autism.

What are the signs of autism spectrum disorder (ASD)?

Signs of ASD range from mild to severely disabling, and every person is different. The following signs are considered to be red flags that indicate your young child may be at risk for autism. If your child shows any of the following signs, please get in touch with your child’s healthcare provider to discuss a referral for an autism evaluation.

The signs include the following:

Your child doesn’t respond to their name being called at all or responds inconsistently.
Your child doesn’t smile widely or make warm, joyful expressions by the age of 6 months.
Your child doesn’t engage in smiling, making sounds and making faces with you or other people by the age of 9 months.
Your child doesn’t babble by 12 months.
No back-and-forth gestures such as showing, pointing, reaching or waving by 12 months.
No words by 16 months.
No meaningful, two-word phrases (not including imitating or repeating) by 24 months.
Any loss of speech, babbling or social skills at any age.

Diagnosis and Tests

How is autism spectrum disorder (ASD) diagnosed?

There are no laboratory tests to determine ASD. However, certain healthcare providers receive specific training and can do screenings and evaluations if needed and who might ask parents or teachers to record observations. These providers might include specialized physicians, psychologists and speech-language pathologists.

Management and Treatment

How is autism spectrum disorder (ASD) treated?

ASD is most often a life-long condition. Both children and adults with autism benefit from behavioral interventions or therapies that can teach new skills to address the core deficits of autism and to reduce the core symptoms. Every child and adult with autism is unique. For this reason, the treatment plan is individualized to meet specific needs. It is best to begin interventions as soon as possible, so the benefits of therapy can continue on throughout the course of life.

Many people with ASD often have additional medical conditions, such as gastrointestinal and feeding issues, seizures and sleep disturbances. Treatment can involve behavioral therapy, medications or both.

Early intensive behavioral treatments involves the entire family and possibly a team of professionals. As your child ages and develops, treatment may be modified to cater to their specific needs.

During adolescence, children benefit from transition services that promote skills of independence essential in adulthood. The focus at that point is on employment opportunities and job skill training.

Outlook / Prognosis

What is the outlook for people with autism spectrum disorder (ASD)?

In many cases, the symptoms of ASD become less pronounced as a child gets older. Parents of children with ASD may need to be flexible and ready to adjust treatment as needed for their child.

People with ASD may go on to live typical lives, but there is often need for continued services and support as they age. The needs depend on the severity of the symptoms. For most, it's a lifelong condition that may require ongoing supports.

A note from Cleveland Clinic

Through research, there has been much that has been learned about autism spectrum disorder over the past 20 years. There is ongoing active research on the causes of ASD, early detection and diagnosis, prevention and treatments.

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Autism Spectrum Disorder