Hyperactivity, depression and inattention caused by snoring? As odd as it may sound, a new study has linked problem behaviors in young children with loud and persistent snoring.

Published online in the journal Pediatrics, the study was led by Dean Beebe, Ph.D., director of the neuropsychology program at Cincinnati Children's Hospital Medical Center. Beebe and his team surveyed the parents of 249 children about their sleep and behaviors. The study revealed that children who snored loudly a minimum of two times a week at the age of 2 and 3 had more behavior problems than children who didn't snore.

Thirty-five percent of the children who were persistent snorers were found to be at risk for behavioral problems.

Persistent, loud snoring happens in about one of every 10 children. Earlier research has shown that sleep marked with sleep-disordered breathing (including snoring, mouth-breathing or apnea) is linked to hyperactivity. The link between snoring and behavior could be connected to hypoxia — decreased oxygen delivery to the brain. 

"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," says Beebe. "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."

"Many preschool children snore for brief periods, [for example] when they have a cold," Beebe told ABC News. "But loud snoring that lasts for months or years is abnormal and may signal a sleep-related breathing problem that could affect a child's behaviors during the day."

Sleep experts say parents who have kids who snore loudly and persistently should inform their pediatricians as soon as they can.

Related on MNN: Why do people snore?