(RxWiki News) If it seems as though more children are being diagnosed with attention deficit hyperactivity disorder (ADHD), it's not your imagination. The numbers really are going up.
A recent study found that rates of ADHD in US children increased over an eight-year period.
By 2011, an additional 2 million children in the US had been diagnosed with ADHD over those diagnosed in 2003.
Most of these children were taking medication for their disorder, the study found.
"Talk to your child's doctor about ADHD treatment."
This study, led by Susanna N. Visser, MS, of the Division of Human Development and Disability at the Centers for Disease Control and Prevention (CDC), aimed to better understand rates of ADHD in the US through the year 2011.
The researchers used data from the 2003, 2007 and 2011 National Surveys of Children's Health regarding ADHD diagnoses and treatment among children aged 4 to 17.
The researchers found that in 2011, a total of 11 percent of all the children and teens had been diagnosed with ADHD at some point. That percentage translates to approximately 6.4 million children in the US.
Among those who had been diagnosed with ADHD at some point or another, 83 percent currently had the disorder — which was about 8.8 percent of all US children.
A little more than two thirds (69 percent) of children with currently diagnosed ADHD were taking medication for the condition.
That means approximately 3.5 million children in the US, or 6.1 percent of kids aged 4 to 17, were taking medication for ADHD.
The researchers found a 42 percent increase in diagnosed ADHD reported by parents in the survey between 2003 and 2011.
Between 2007 and 2011, there was a 28 percent increase in the number of children who were taking medication for ADHD.
"Parent-reported prevalence estimates provide insight into the demand that this population has on the systems supporting them, and these data suggest that the impact of ADHD may be increasing," the researchers wrote.
"Based on this report’s estimates, the cross-sector costs associated with ADHD likely exceed the previously estimated upper bound of $78 billion," they wrote.
The authors noted that rates of ADHD varied from state to state, sometimes quite dramatically. The lowest current rate of ADHD was 4.2 percent in Nevada while the two highest rates were 14.6 percent in Arkansas and 14.8 percent in Kentucky.
However, the authors did not address what the possible reasons for the geographical differences might be. The highest rates were concentrated in states in the East, the South and in the eastern Midwest.
"This report provides valuable information that some will view as encouraging and others as worrisome," said Glen Elliott, MD, PhD, a clinical professor at the Stanford University Department of Psychiatry and Behavioral Sciences who was not involved in the study.
"Based on parent report, ADHD diagnoses rose substantially from 2007 to 2011, as did the use of medication among those with an ADHD diagnosis," he said. "This does not necessarily mean actual prevalence of ADHD is changing so much as recognition of the disorder and willingness to treat it."
Dr. Elliott also noted that most of the increase in medication use has occurred in mid- and older teens, "a group that other researchers have suggested especially might benefit from ongoing treatment," he said.
"The variability across states is fascinating and emphasizes that this is still a clinical diagnosis without an objective test to affirm it," Dr. Elliott said.
This study was published November 19 in the Journal of the American Academy of Child & Adolescent Psychiatry.
The research was funded by the CDC. The authors reported no potential conflicts of interest.