Many autistic children with social and communication problems benefit from intensive therapy and about 10 per cent "bloom," enjoying rapid improvement in social skills as they grow older, US researchers said on Monday.
Most of the children in the study who benefited were white and came from wealthy homes, likely reflecting difference in access to treatment, and very few had intellectual disabilities in addition to their social problems, the researchers said.
According to the latest figures from the US Centers for Disease Control and Prevention 1 in 88 US children have autism, a spectrum of disorders that ranges from severe communication and intellectual disability to much milder symptoms seen in children with Asperger's syndrome.
"Most children get at least a little better over time," said Christine Fountain, an autism researcher at Columbia University in New York, whose study was published in the journal Pediatrics.
Autism is marked by a group of symptoms, all arising from atypical brain development that causes problems with socialization, communication and behavior.
Although the disorder can be mild or severe, in general children with autism have trouble communicating and making friends. Many avoid eye contact with people, hampering their ability to understand what others are thinking and feeling.
For their study, Fountain and colleagues studied the different growth trajectories of close to 7,000 autistic children in California, aged 2 to 14. The children had undergone at least four evaluations in which staff recorded their social and communication difficulties and their repetitive behaviors.
The researchers found that especially when it came to social and communication scores, most children improved over time.
Of the children, about 10 per cent saw rapid gains, moving from severely affected to high functioning, a group the researchers dubbed "social bloomers."
But they noticed that many of the children that fell into this group had non-Hispanic, white, well-educated mothers. Minority children with less-educated mothers or children with intellectual disabilities were very unlikely to make rapid gains, they said.
The researchers did not have information about the specific treatment each child received. There is limited evidence on what type of autism treatment might be helpful but behavioral therapy typically includes language- and communication-based exercises and some children are also given medication including antidepressants.
Johnny Matson, an autism researcher at Louisiana State University in Baton Rouge, said the findings reinforce prior studies that have found children with autism and a normal IQ improve more from intensive therapy that those who have both autism and intellectual disabilities.
Matson, who was not involved with the study, said gaps in improvement based on parents' race and education are probably about access to good-quality treatment.
But he said "those gaps are narrowing very rapidly" because of laws requiring insurance companies to cover intensive treatment for all children with autism.
Fountain said the findings suggest that providing equal access to the best autism treatment for minority and less well-off kids will be important going forward. Some states including California provide services to all kids with autism regardless of their ability to pay, she added, but others do not.
She said children's specific conditions and symptoms may play a role in their long-term improvement but the treatment they get at certain points in development also is likely to be important.
Both Fountain and Matson said parents of children with autism should be persistent in making sure their kids get the help they need but agreed they also can be optimistic