Kids who snore or have sleep apnea — long pauses in breathing during their sleep — are more likely to develop behavioral problems than kids who breathe normally while asleep, a new study suggests.

After following more than 11,000 children for six years, researchers found that kids with breathing problems during sleep were at least 40 percent more likely to develop behavioral problems, such as hyperactivity and aggression, by age 7.

Breathing problems that can occur during sleep include frequent snoring, open-mouthed breathing and sleep apnea.

“This is the strongest evidence to date that snoring, mouth breathing and apnea can have serious behavioral and social-emotional consequences for children,” said lead researcher Karen Bonuck, a family medicine expert at Albert Einstein College of Medicine at Yeshiva University in New York.

“Parents and pediatricians alike should be paying closer attention to sleep-disordered breathing in young children, perhaps as early as the first year of life,” she said.

The study was published today (March 5) in the journal Pediatrics.

Sleep-disordered breathing can start early

About 1 in 10 children snore regularly, and 2 to 4 percent have sleep apnea, according to the American Academy of Otolaryngology-Head and Neck Surgery.

The breathing problems are most common in children between 2 and 6 years old, but can also occur in younger children.

Common causes of the breathing problems are enlarged tonsils and adenoids, which are found in the upper part of the throat. Other causes include obesity, skull and facial deformities, and an inability of the brain to control breathing.

An increased risk of behavior problems

Bonuck and colleagues analyzed 11,000 children enrolled in a United Kingdom study. They compared 5,000 normal breathing children with about 6,000 children who had breathing problems during their sleep.

Parents were asked to fill out questionnaires about their children's sleeping patterns from the time the children were 6 months old until they were almost 6 years old.

When their children reached age 4, and again at age 7, parents completed a questionnaire designed to measure five types of behavior, including hyperactivity, emotional symptoms such as anxiety and depression, peer relationship problems, conduct problems such as following rules and social behavior toward others.

Children who had breathing problems as early as 6 months had a 50 percent increased risk of developing behavioral problems by age 7, compared with normally breathing children.

“The biggest increase was in hyperactivity,” Bonuck said, “but we saw significant increases across all five behavioral measures.”

Children with the most serious behavioral problems were those with sleep-disordered breathing symptoms that persisted and became most severe at 30 months.

Bonuck recommends that parents who suspect their child has breathing problems during sleep “should ask their pediatrician or family physician if their child needs to be evaluated by an otolaryngologist (a ear, nose and throat physician) or a sleep specialist.”

Pass it on: Young children who breathe abnormally while sleep are prone to developing behavior problems.

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