Autism symptoms can improve into adulthood

NEW YORK (Reuters Health) - Autism symptoms have a tendency to lessen with age, according to a new study.

Dr. Paul T. Shattuck of Washington University in St. Louis and colleagues looked at how behavior in 241 adolescents and adults with autism changed over 4.5 years. The study subjects were initially aged 10 to 52 years; their average age was 22 years.

For all major symptoms of autism, "the percentage of people who improved was always greater than the percentage who worsened," Shattuck said in a statement. "If there was significant symptom change over time, it was always in the direction of improvement, though there was always a group in the middle that showed no change."

The researchers looked at a broad range of typical autistic symptoms including impaired verbal and nonverbal communication, impaired social interaction and repetitive behaviors. They also looked at broader maladaptive behaviors such as aggression and self-injury that are not specific to autism.

"There was significant improvement for 19 of the 32 autism symptoms and seven of the eight maladaptive behaviors," the authors report in the Journal of Autism and Developmental Disorders.

They also found that, relative to adolescents, older subjects (age 31 and older) had fewer maladaptive behaviors and experienced more improvement in these behaviors over time.

Individuals with mental retardation exhibited more autism symptoms and maladaptive behaviors than those without mental retardation and they improved less over time.

This study, Shattuck noted, shows that individuals with autism spectrum disorders continue to grow and change over time. "Their development is not frozen in time and forever the same," Shattuck said.

SOURCE: Journal of Autism and Developmental Disorders, Sept/Oct 2007.