NEWS

[2009-12-19]
NYTimes- Study Increases Prevalence of Autism

Study Increases Prevalence of Autism
By BENEDICT CAREY

Nearly 1 in 100 American 8-year-olds struggle with autism, Asperger’s syndrome or a related developmental problem, according to a study that health officials released on Friday.

The estimate is the highest to date of so-called autism spectrum disorders from the Centers for Disease Control and Prevention, which tracks health trends. The spectrum includes a range of disorders, from severe autism to milder forms like Asperger’s to “pervasive developmental disorder,” a nonspecific diagnosis given to many children with social difficulties or some kinds of learning and sensory problems.

The finding is based on an analysis of medical and school records of some 400,000 children around the country; the researchers did not meet or interview the children.

Prevalence estimates for these disorders have increased so sharply in recent years — to 1 in 150 in 2007, from 1 in 300 in the early 2000s — that scientists have debated whether in fact the disorder is more common, or diagnosed more often as a result of higher awareness.

“A simple explanation is not apparent, and a true increase in risk cannot be ruled out,” Catherine Rice, lead author of the study and a behavioral health scientist at the National Center on Birth Defects and Developmental Disabilities, said in a conference call with reporters.

Advocacy groups said the new numbers confirmed that the disorder was increasing and called for increased financing for research and treatment.

There is no blood test for autism; doctors diagnose it and related disorders by observation and interviews with children and their families, and prevalence estimates vary depending on how studies are done.

The new estimate is about the same as one from a study published in October, which found a rate of slightly more than 1 in 100 children who received a diagnosis. Yet that study, based on a phone survey of 78,000 households, also found that almost 40 percent of the children who had received an autism spectrum diagnosis grew out of it or no longer had the diagnosis.