Klein noted that although such treatment was automatically stopped at the age of 13 because of the fear among clinicians that stimulants could prove addictive, the thinking on that has since changed.
"It is possible that if we keep treating children to an older age they might do much better," she added.
Steven Safren, director of behavioral medicine in the department of psychiatry at Massachusetts General Hospital in Boston, said the findings "are in line with prior research."
"I think that what happens is that kids are diagnosed and treated while in childhood, while their parents have responsibility for it," he said. Unfortunately, there's not a lot of focus on treatments for adults with ADHD, Safren added.
For more on ADHD, visit the U.S. National Institute of Mental Health.
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