Youngest children in class more likely to be diagnosed with ADHD
Younger children in the same grade with peers that may be almost 1 year older are significantly more likely to be diagnosed with attention-deficit/hyperactivity disorder. This may lead to overdiagnosis and overprescribing of medications among these children, according to researchers.
Richard L. Morrow, MA, and colleagues from the University of British Columbia examined a cohort of 937,943 children in British Columbia, where the cut-off for entry into kindergarten or grade one is Dec. 31. Children were included in the 11-year study at some point between the ages of 6 and 12 years.
Researchers compared children who were nearly 1 year apart in age (those born in December and those born in January nearly 1 year earlier). When divided between boys and girls, the younger boys were 30% more likely to have a diagnosis of ADHD, and the younger girls were 70% more likely to have a diagnosis of ADHD. Similarly, the younger boys were 41% more likely, and girls 77% more likely, to have a prescription for a medication to treat ADHD, compared with their older peers.
The relative age of the children is influencing whether they are diagnosed and treated for ADHD, Morrow said in a press release. Our study suggests younger, less mature children are inappropriately being labeled and treated. It is important not to expose children to potential harms from unnecessary diagnosis and use of medications.
Disclosure: Drs. Morrow, Garland, Wright, Maclure and Dormuth received a Catalyst grant from the Canadian Institutes of Health Research to study postmarket drug safety and effectiveness. Dr. Maclure is employed by the University of British Columbia and the British Columbia Ministry of Health. Dr. Taylor is employed by the British Columbia Ministry of Health. No other competing interests were declared.