The stimulants used to treat ADHD might be making kids fat, a new study suggests.
A study of more than 160,000 youngsters found that kids with Attention Deficit and Hyperactivity Disorder who received stimulants were at increased risk of becoming obese as they hit their teens. In contrast, kids with ADHD who took non-stimulant medications or got no therapy were very comparable, in terms of weight gain, to kids who didn’t have the disorder.
“Our data suggest that stimulant use during childhood might have lifelong effects,” said Dr. Brian Schwartz, the study’s lead author and a professor of environmental health sciences, epidemiology, and medicine at the Johns Hopkins Bloomberg School of Public Health and senior investigator at the Geisinger Center for Health Research. “They might reset all sorts of physical properties and appetite parameters.”
The new research may have uncovered a growing public health issue, Schwartz said. “Our data would seem to offer a lot of cause for concern with respect to prescribing stimulants,” he explained.
Schwartz and his colleagues started the study because they were perplexed by the apparent paradox of hyperactive kids being prone to obesity. They scrutinized 12 years-worth of medical information from 163,820 Pennsylvania children, 13,427 of whom received an ADHD diagnosis.
While the younger kids with ADHD who received no medication or non-stimulant treatment did have higher BMIs early on compared to kids without the disorder, their weight gain seemed to level off as they hit adolescence.
Kids with ADHD who received stimulants were thinner early on, but their weight rebounded as they hit their teens leaving them heavier than all the other kids in the study.
The effect was more pronounced the longer kids took stimulants and the younger they were when they started.
“The reason this is such a big deal is that 11 percent of children have ADHD and around 75 percent are on stimulant medications,” said Dr. Naomi Steiner, a developmental and behavioral pediatrician at the Floating Hospital for Children at Tufts Medical Center. “With the childhood obesity epidemic, that’s a huge chunk of the population. It does become a kind of public health alert.”
That doesn’t mean that kids with ADHD shouldn’t be taking stimulants, Steiner said. “But I think this informs pediatricians and families about the long term effects of stimulants,” she added.
At present we don’t even know how stimulants work in kids with ADHD, said Sandra K. Loo, director of pediatric neuropsychology and an associate professor of psychiatry at the David Geffen School of Medicine at UCLA. Some recent research suggests that stimulants help with brain development.
The new study may offer a window on some of the long term effects of stimulants.
“The data they present are sound,” Loo said. “They show that if stimulants are taken early in life and for a long time it seems to leave children with an increased BMI later on. But the mechanism through which that happens is still unknown. This is a piece of the puzzle, but there needs to be more research.”