One of the most popular and effective drugs used to treat Attention Deficit / Hyperactivity Disorder (ADHD) changes the brains of boys with the disorder, a new study shows.
Although researchers could not say for sure whether the changes were good or bad, one ADHD expert believes the findings suggest that the changes are helping young men with the disorder.
White matter is affected
For the study, investigators estimated groups of boys and young adults with ADHD who had never taken methylphenidate (sold under the Ritalin and Concert brands). Dutch researchers found that among boys, taking drugs increased white matter in the brain. White matter is key to learning and other brain functions, including coordinating communication between different regions of the brain.
The drug "permanently affects the development of white matter in boys with ADHD, and this is probably because the brain is still developing because we did not notice these changes in men with ADHD with the mature brains we studied," the study's author said. Dr. Lisbeth Reneman. She is a professor of translational neuroradiology at the University of Amsterdam.
"We still have to determine the long-term implications of our findings, [but] in the meantime … we think that the drug should be prescribed only to children who actually have ADHD and are significantly affected by it, "Reneman added.
About 9% of US children between the ages of two and 17 have ever been diagnosed with ADHD, according to the US Centers for Disease Control and Prevention. In 2016, over 5% of all children in the United States were taking medication to treat the disorder, whose symptoms include attention problems, task organization, and impulsive behavior.
While Reneman said the study was not designed to determine whether changes in white matter in boys taking methylphenidate were good or bad, an American expert interpreted the changes as "normalizing" the brain.
The importance of early treatment
"Normalizing white matter for treated children is something we hope for and wish it to be true, and this [study] it gives validation to that, "said Dr. Alan Geller. He is a child psychiatrist, adolescent and adult in private practice and an attending psychiatrist at Grace Square Hospital in New York.
"This is a population at risk, when left untreated, of antisocial and opposition behaviors, school problems and family problems and in the end that's what we want to hear – that treating children with ADHD early will help," Geller added. who was not included in the study.
In a new study, Reneman and her colleagues divided 50 boys between the ages of 10 and 12 and 48 young adult men – all of whom never took methylphenidate – into two equal groups. For 16 weeks, one group received methylphenidate and the other received placebo.
Prior to the study, and one week after treatment, all participants underwent MRI scans of the brain, including a technique that evaluated white matter.
In boys with ADHD, four-month treatment with methylphenidate was associated with increased white matter. But the effects of the drug appear to be age-dependent, since they did not appear in adults who took it, the study authors said.
Reneman also said the results could not be generalized, meaning that girls with ADHD would experience the same changes in white matter from the drug, "because girls differ significantly in the development of white matter in the brain."
Long term implications
But Reneman said he was "pretty sure the effects were due to methylphenidate, not something else", as previous research had yielded similar results. The new research also created a "higher level of evidence" by assigning children with methylphenidate or placebo to ADHD and measuring white matter before and after treatment.
Renemann and her colleagues continue to explore the issue, studying the long-term implications of these findings for ADHD behavior. Many ADHD patients have been taking medication for many years, the study authors noted, so it is important to determine long-term effects.
Geller said that based on these findings, he would continue to recommend early treatment of children with ADHD.
"I see this [brain change] as improvement or normalization because that's what I see clinically – I see that behavior, attention and socialization improve with treatment, and I kind of go back and assume that changes in the brain are beneficial, "he said.
"But the study does not conclude that," Geller admitted. "I suppose I'm more hopeful and have the clinical evidence to support me."
The study was published in the journal Radiology.
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