Symptoms during teen years
During the teen years, the patterns of behavior often change. Many teens gain skills but still lag behind in their ability to relate to and understand others. Puberty and emerging sexuality may be more difficult for teens who have autism than for others this age. Teens are at an increased risk for developing problems related to depression, anxiety, and epilepsy.
Symptoms in adulthood
Some adults with autism are able to work and live on their own. The degree to which an adult with autism can lead an independent life is related to intelligence and ability to communicate. At least 33% are able to achieve at least partial independence.
Some adults with autism need a lot of assistance, especially those with low intelligence who are unable to speak. Part- or full-time supervision can be provided by residential treatment programs. At the other end of the spectrum, adults with high-functioning autism are often successful in their professions and able to live independently, although they typically continue to have some difficulties relating to other people. These individuals usually have average to above-average intelligence.
Other symptoms
Many people with autism have symptoms similar to attention deficit hyperactivity disorder (ADHD). But these symptoms, especially problems with social relationships, are more severe for people with autism. For more information, see the topic Attention Deficit Hyperactivity Disorder.
About 10% of people with autism have some form of savant skills-special limited gifts such as memorizing lists, calculating calendar dates, drawing, or musical ability.
Many people with autism have unusual sensory perceptions. For example, they may describe a light touch as painful and deep pressure as providing a calming feeling. Others may not feel pain at all. Some people with autism have strong food likes and dislikes and unusual preoccupations.
Sleep problems occur in about 40% to 70% of people with autism.
Other conditions
Autism is one of several types of pervasive developmental disorders (PDDs), also called autism spectrum disorders (ASD). It is not unusual for autism to be confused with other PDDs, such as Asperger's disorder or syndrome, or to have overlapping symptoms. A similar condition is called pervasive developmental disorder-NOS (not otherwise specified). PDD-NOS occurs when children display similar behaviors but do not meet the criteria for autism. It is commonly called just PDD. In addition, other conditions with similar symptoms may also have similarities to or occur with autism.
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