Lead author Dean Beebe, director of the neuropsychology program at Cincinnati Children's Hospital Medical Center and colleagues studied 249 children, and surveyed the children's moms about their kids' sleep and behaviors.
The study, published in the journal Pediatrics, found children who snored loudly at least twice a week at ages 2 and 3 had more behavior problems than children who either don't snore or who snored at age 2 or 3 but not at both ages.
"A lot of kids snore every so often, and cartoons make snoring look cute or funny. But loud snoring that lasts for months is not normal, and anything that puts young kids at that much risk for behavioral problems is neither cute nor funny," Beebe said in a statement. "That kind of snoring can be a sign of real breathing problems at night that are treatable. I encourage parents to talk to their child's doctor about loud snoring, especially if it happens a lot and persists over time."
Persistent, loud snoring occurs in approximately 1-of-10 children, Beebe said.
Infant breastfeeding, especially over longer periods of time, seems to protect children against persistent snoring, Beebe added.