Louise O'Brien, assistant professor at the University of Michigan Sleep Disorders Center, and colleagues say the study involved public elementary school students in Ypsilanti, Mich., who had exhibited conduct problems like bullying or discipline referrals.
The study, published in the journal Sleep Medicine, found that there was a two-fold higher risk for symptoms of sleep-disordered breathing, particularly daytime sleepiness, among these students.
"What this study does is raise the possibility that poor sleep, from whatever cause, can indeed play into bullying or other aggressive behaviors -- a major problem that many schools are trying to address," O'Brien says in a statement. "Our schools do push the importance of healthy eating and exercise, but this study highlights that good sleep is just as essential to a healthy lifestyle."
The study showed sleepiness, not snoring -- which is often a more obvious symptom associated with sleep-disordered breathing -- appears to be the biggest driver of the behavior problems, the researchers say.
O'Brien says a longitudinal study is needed and if sleepiness does contribute to aggressive behavior as this study suggests, a significant proportion of bullying in children might be eliminated by efforts to reduce children's daytime sleepiness.