(NaturalNews) The rate at which children are diagnosed with attention deficit hyperactivity disorder (ADHD) jumped dramatically over the past 10 years, according to a study conducted by researchers from Kaiser Permanente, the West Los Angeles Medical Center and the University of Medicine and Dentistry, New Jersey-School Public Health and published in the journal JAMA Pediatrics (formerly Archives of Pediatrics and Adolescent Medicine).
ADHD is officially classified as a neurobehavioral disorder. According to the Centers for Disease Control and Prevention, ADHD affects between four and 12 percent of all school-aged children in the United States, making it one of the most common childhood disorders. Between 66 and 85 percent of these children maintain the diagnosis into adolescence and adulthood.
Yet, both the rate at which children are diagnosed with ADHD, and even the existence of the disorder itself, have proven controversial, with many critics alleging that doctors are now too quick to slap children with the label.
The implications of the controversy are significant: treatment of children with ADHD runs between $36 billion and $52 billion per year in the United States. Children diagnosed with ADHD are more likely to miss school, have trouble learning, suffer from injury, and have troubled relationships with family and peers.
Strong demographic disparities
The researchers examined electronic health records of approximately 850,000 children between the ages of five and 11 who had been treated between 2001 and 2010 at Kaiser Permanente Southern California. Nearly five percent of all children in the study (39,200) had received a diagnosis of ADHD. The diagnosis was most common among non-Hispanic white children, who had a 5.6 percent diagnosis rate. Black children had the second-highest rate (4.1 percent), followed by Hispanics (2.5 percent) and Asian/Pacific Islanders (1.2 percent).
The researchers found that between 2001 and 2010, the rate at which children were diagnosed with ADHD increased by 24 percent, from 2.5 percent to 3.1 percent. The greatest increase in ADHD diagnoses came among black children between the ages of five and 11, where the rate increased from 2.6 percent to 4.1 percent - a 70 percent relative increase. Among girls, the increase was actually 90 percent. The relative increase among Hispanics was nearly as high, a 60 percent increase from 1.7 percent to 2.5 percent.
The rates of increase among other racial and ethnic groups were substantially lower. Among white children, the diagnosis rate increased 30 percent, from 4.7 percent to 5.6 percent, while among Asian and Pacific Islanders and other groups it neither increased nor decreased.
In general, boys were three times more likely to receive an ADHD diagnosis than girls were, while children from families making more than $30,000 per year were 20 percent more likely to be diagnosed than children from families making less than that.
"Our study findings suggest that there may be a large number of factors that affect ADHD diagnosis rates, including cultural factors that may influence the treatment-seeking behavior of some groups," said study lead author Darios Getahun.