There is a 43 percent increase in the prevalence of ADHD diagnoses in the first decade of the century, with more than one in 10 youths now diagnosed with attention deficit hyperactivity disorder in the United States, said researchers.
ADHD is the most commonly identified mental disorder in the United States, often treated with psychological therapy and prescription stimulants like Ritalin to improve behavior and focus. Its precise causes are unknown, though some research has pointed to difficulties during pregnancy, exposure to toxins and family history as playing a role.
‘The prevalence of ADHD diagnoses in American children and teens increased from 8.4 percent in 2003 to 12 percent in 2011.
The findings in the Journal of Clinical Psychiatry
show that 12 percent of American children and teens had ADHD in 2011, a significant rise over the 8.4 percent reported by parents in the same survey taken in 2003. When researchers looked specifically at teenagers, they found the diagnoses had risen 52 percent since 2003.
"This analysis suggests that 5.8 million US children ages five to 17 now have this diagnosis, which can cause inattention and behavioral difficulties," said lead researcher Sean Cleary, an associate professor of epidemiology and biostatistics at Milken Institute School of Public Health at the George Washington University.
While ADHD has traditionally been more common among boys than girls, researchers found that parent-reported prevalence for girls diagnosed with ADHD rose 55 percent in eight years -- from 4.3 percent in 2003 to 7.3 percent in 2011. Among boys, it rose 40 percent.
The data for the study came from the Maternal and Child Health Bureau and the National Center for Health Statistics, a part of the US Centers for Disease Control and Prevention.Sharp jumps
"We found rising rates of ADHD overall and very sharp jumps in certain subgroups," Cleary said.
Hispanics in particular reported an 83 percent rise in ADHD diagnosis during the eight-year study period.
The rate of ADHD rose 107 percent among non-English speakers, and 71 percent among children with parents in so-called "other" parent marital situations -- such as living with a single father, legal guardian, or grandparent, the study found.
Study authors said their research was not designed to look for the underlying reasons for changes in prevalence. However, past studies have suggested the recent rise in US prevalence of ADHD may include changes in special-education policy or increased public awareness of ADHD.
Other studies have suggested that there has been no objective rise in ADHD since the 1960s, but rather changes in definition and diagnosis that account for more cases being recognized.
According to Andrew Adesman, chief of developmental and behavioral pediatrics at Cohen Children's Medical Center of New York, the latest data is "not surprising" and "supports the general impression that more children and adolescents are being diagnosed with ADHD."
However, Adesman -- who was not involved in the study -- said that while the statistics are convincing, "it does not help us understand why these increases are being observed."