Black and Hispanic children are half as likely to be diagnosed with attention-deficit/hyperactivity disorder (ADHD) as their white peers, according to a new study that followed U.S. kindergarteners through middle school.
"We're seeing that the disparities occur as early as kindergarten and then remain and continue until the end of eighth grade," said Paul Morgan, who led the study at Pennsylvania State University in University Park.
"It's a consistent pattern of what we're interpreting as comparative underdiagnosis for minority populations," he said.
That's a concern, Morgan said, because it means some kids who could benefit from treatment - including medication or talk therapy - and extra help in the classroom may be missing out.
The researchers also found that compared to white children with the condition, minority kids who were diagnosed with ADHD were less likely to be prescribed medications, which include the stimulants Vyvanse, Ritalin and Concerta.
They tracked 15,100 kids from the kindergarten class of 1998-1999 using regular parent surveys.
At each survey point - kindergarten and first, third, fifth and eighth grades - white children were most likely to have ADHD. All races followed a similar trend over time, with new diagnoses peaking around third grade.
By the spring of eighth grade, 7 percent of white kids had received an ADHD diagnosis, their parents reported. In comparison, 3 percent of black kids and just over 4 percent of Hispanic children had been diagnosed.
Factors such as a mother's age at birth and family income didn't explain those differences, nor did teacher reports of each child's behavior and learning, Morgan's team wrote on Monday in Pediatrics. Their study was funded by the National Institutes of Health.
"There just seems to be more wariness and concern in African American groups," both about being diagnosed with ADHD and the medications used to treat the condition, said Dr. Tanya Froehlich, an ADHD researcher at Cincinnati Children's Hospital Medical Center.
"A lot of people are very concerned about their child being labeled and their child being stigmatized both in the school and socially," Froehlich, who wasn't involved in the new research, said.
Morgan noted that children with ADHD are allowed certain adaptations and extra help in the classroom.
"If you've got certain groups of kids with a disorder who are not being picked up … they might not be accessing treatment that can help in terms of their school-based functioning," he said. That, in turn, can lead to poor self-esteem and acting out.
Untreated ADHD has also been linked to substance abuse, anxiety and depression as children grow older.
Talk therapy and parent training are options for families that don't want to use medication, Morgan said.
"For someone who truly has ADHD, there's so much that can be done to help that child and to help prevent some of these negative consequences," Froehlich said.
Morgan said evidence suggests minority children are exposed to more of the risk factors for ADHD, such as being born small. So if anything, researchers would expect them to be diagnosed with the disorder more often.
The new study can't prove the findings represent underdiagnosis of minorities, rather than overdiagnosis of white children, according to Froehlich. But if kids are having problems at school or at home and aren't seeing a doctor, that's a concern, she added.
"It's really important if parents feel their child might have a problem to get them evaluated by a trained medical professional," she said.