Classroom's Youngest Kids Have Higher Rates of ADHD Diagnoses

By Kelly Young

Edited by Susan Sadoughi, MD, and Richard Saitz, MD, MPH, FACP, DFASAM

The youngest children in a classroom are more likely to be diagnosed with attention-deficit/hyperactivity disorder (ADHD) than their older classmates, according to a study in the New England Journal of Medicine.

Using an insurance claims database, researchers followed roughly 400,000 children born between 2007 and 2009. In the 18 states that used Sept. 1 as the birth-date cutoff for starting kindergarten, children born in August, who were among the youngest in their grade, had 34% greater likelihood of being diagnosed with ADHD through age 7 than did children born in September, who were the oldest (85 vs. 64 per 10,000 children). The difference was only significant among boys.

See what Dr. Jenny Radesky has to say about this study in NEJM Journal Watch Pediatrics and Adolescent Medicine.