(HealthDay)—Minority children are significantly less likely than their white peers to be diagnosed or treated for attention-deficit/hyperactivity disorder (ADHD), new research shows.
The study, which is published online June 24 and in the July print issue of the journal Pediatrics, followed more than 17,000 children across the nation from kindergarten to eighth grade. Researchers regularly asked parents if their children had been diagnosed with ADHD.
Even after taking into account a host of factors that may influence behavior, attention and access to health care, researchers found that Hispanic and Asian children and those of other races were about half as likely to receive a diagnosis as whites. Blacks were about two-thirds less likely to be recognized as having problems with attention or hyperactivity as whites.
In addition, when minority children were diagnosed, they were less likely to receive medication than white kids with ADHD, the investigators found.
The study can't say, however, whether the differences mean that ADHD is being underdiagnosed in minorities or overdiagnosed in whites. Previous research has raised both possibilities.
A study published in the journal Clinical Psychology Review in 2009, for example, found that despite having more symptoms of distractibility and hyperactivity, black children were diagnosed with ADHD less often than whites.
On the other hand, a study published in April 2012 in the Canadian Medical Association Journal found that the youngest children in their school class were more likely to be diagnosed compared to the oldest children in those grades, suggesting that some doctors and teachers may mistake immaturity for ADHD, leading to overdiagnosis.
One expert suggested that socioeconomic and cultural differences may be at work.
Doctors still don't know if one or both problems may be driving the rates of lower diagnoses in minorities seen in the current study, said Dr. Tanya Froehlich, a pediatrician at Cincinnati Children's Hospital in Ohio.
"It does seem to be clear that there are some cultural differences at work, and also probably some differences in access to health care and access to health care information," said Froehlich, who was not involved in the research.
For example, the study noted that children without health insurance were less likely to be diagnosed with ADHD than children who had coverage. Kids from lower-income families were also less likely to be diagnosed.
Yet, children with older mothers, who tend to be more highly educated, and those with parents who spoke to doctors in English were more likely to be diagnosed with the condition. Both those factors are signs that access to health care and awareness of the problem may also be playing a role.
Several risk factors for ADHD occur more often in minority children than in whites. Those include a lower household income, less educated parents and low birth weight.
"What that suggests in our study is that there are children who are likely deserving of a diagnosis, but who aren't receiving a diagnosis, which raises the question of a lack of treatment," said study author Paul Morgan, director of the educational risk initiative at Pennsylvania State University in University Park, Pa.
The consequences of ADHD can be serious if the condition is left untreated.
"We know that people with ADHD have higher rates of failing a grade in school, lower academic achievement, lower achievement in their jobs, higher rates of incarceration, higher rates of substance abuse, more problems with relationships, and higher rates of depression and anxiety," Froehlich said. "It is extensive."
There's some evidence that treatment, either with behavioral therapies or medication, can improve the outlook for affected children.
"Definitely, we want all kids to be treated and to have the best chance possible for success in life," Froehlich said. "So if people truly have ADHD and they're not identified, that's going to hold them back."
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For more on ADHD, visit the U.S. Centers for Disease Control and Prevention.