- What is autism spectrum disorder (ASD)?
- What are the symptoms of ASD?
- How is ASD diagnosed?
- What are some other conditions that children with ASD may have?
- How is ASD treated?
- How common is ASD?
- What causes ASD?
- What efforts are under way to improve the detection and treatment of ASD?
- How can I help a child who has ASD?
- For More Information on Autism Spectrum Disorder
What are some other conditions that children with ASD may have?
Many children with autism spectrum disorder (ASD) either overreact or underreact to certain sights, sounds, smells, textures, and tastes. For example, some may:
- Dislike or show discomfort from a light touch or the feel of clothes on their skin
- Experience pain from certain sounds, like a vacuum cleaner, a ringing telephone, or a sudden storm; sometimes they will cover their ears and scream
- Have no reaction to intense cold or pain.
Researchers are trying to determine if these unusual reactions are related to differences in integrating multiple types of information from the senses.
Children with ASD tend to have problems falling asleep or staying asleep, or have other sleep problems.15 These problems make it harder for them to pay attention, reduce their ability to function, and lead to poor behavior. In addition, parents of children with ASD and sleep problems tend to report greater family stress and poorer overall health among themselves.
Fortunately, sleep problems can often be treated with changes in behavior, such as following a sleep schedule or creating a bedtime routine. Some children may sleep better using medications such as melatonin, which is a hormone that helps regulate the body's sleep-wake cycle. Like any medication, melatonin can have unwanted side effects. Talk to your child's doctor about possible risks and benefits before giving your child melatonin. Treating sleep problems in children with ASD may improve the child's overall behavior and functioning, as well as relieve family stress.16
Many children with ASD have some degree of intellectual disability. When tested, some areas of ability may be normal, while others—especially cognitive (thinking) and language abilities—may be relatively weak. For example, a child with ASD may do well on tasks related to sight (such as putting a puzzle together) but may not do as well on language-based problem-solving tasks. Children with a form of ASD like Asperger syndrome often have average or above-average language skills and do not show delays in cognitive ability or speech.
One in four children with ASD has seizures, often starting either in early childhood or during the teen years.17 Seizures, caused by abnormal electrical activity in the brain, can result in
- A short-term loss of consciousness, or a blackout
- Convulsions, which are uncontrollable shaking of the whole body, or unusual movements
- Staring spells.
Sometimes lack of sleep or a high fever can trigger a seizure. An electroencephalogram (EEG), a nonsurgical test that records electrical activity in the brain, can help confirm whether a child is having seizures. However, some children with ASD have abnormal EEGs even if they are not having seizures.
Seizures can be treated with medicines called anticonvulsants. Some seizure medicines affect behavior; changes in behavior should be closely watched in children with ASD. In most cases, a doctor will use the lowest dose of medicine that works for the child. Anticonvulsants usually reduce the number of seizures but may not prevent all of them.
For more information about medications, see the NIMH online booklet, "Medications". None of these medications have been approved by the FDA to specifically treat symptoms of ASD.
Fragile X syndrome
Fragile X syndrome is a genetic disorder and is the most common form of inherited intellectual disability,18 causing symptoms similar to ASD. The name refers to one part of the X chromosome that has a defective piece that appears pinched and fragile when viewed with a microscope. Fragile X syndrome results from a change, called a mutation, on a single gene. This mutation, in effect, turns off the gene. Some people may have only a small mutation and not show any symptoms, while others have a larger mutation and more severe symptoms.19
Around 1 in 3 children who have Fragile X syndrome also meet the diagnostic criteria for ASD, and about 1 in 25 children diagnosed with ASD have the mutation that causes Fragile X syndrome.19
Because this disorder is inherited, children with ASD should be checked for Fragile X, especially if the parents want to have more children. Other family members who are planning to have children may also want to be checked for Fragile X syndrome. For more information on Fragile X, see the Eunice Kennedy Shriver National Institute of Child Health and Human Development website.
Tuberous sclerosis is a rare genetic disorder that causes noncancerous tumors to grow in the brain and other vital organs. Tuberous sclerosis occurs in 1 to 4 percent of people with ASD.18,20 A genetic mutation causes the disorder, which has also been linked to mental retardation, epilepsy, and many other physical and mental health problems. There is no cure for tuberous sclerosis, but many symptoms can be treated.
Some parents of children with ASD report that their child has frequent gastrointestinal (GI) or digestion problems, including stomach pain, diarrhea, constipation, acid reflux, vomiting, or bloating. Food allergies may also cause problems for children with ASD.21 It's unclear whether children with ASD are more likely to have GI problems than typically developing children.22,23 If your child has GI problems, a doctor who specializes in GI problems, called a gastroenterologist, can help find the cause and suggest appropriate treatment.
Some studies have reported that children with ASD seem to have more GI symptoms, but these findings may not apply to all children with ASD. For example, a recent study found that children with ASD in Minnesota were more likely to have physical and behavioral difficulties related to diet (for example, lactose intolerance or insisting on certain foods), as well as constipation, than children without ASD.23 The researchers suggested that children with ASD may not have underlying GI problems, but that their behavior may create GI symptoms—for example, a child who insists on eating only certain foods may not get enough fiber or fluids in his or her diet, which leads to constipation.
Some parents may try to put their child on a special diet to control ASD or GI symptoms. While some children may benefit from limiting certain foods, there is no strong evidence that these special diets reduce ASD symptoms.24 If you want to try a special diet, first talk with a doctor or a nutrition expert to make sure your child's nutritional needs are being met.
Co-occurring mental disorders
Children with ASD can also develop mental disorders such as anxiety disorders, attention deficit hyperactivity disorder (ADHD), or depression. Research shows that people with ASD are at higher risk for some mental disorders than people without ASD.25 Managing these co-occurring conditions with medications or behavioral therapy, which teaches children how to control their behavior, can reduce symptoms that appear to worsen a child's ASD symptoms. Controlling these conditions will allow children with ASD to focus more on managing the ASD.26