Snoring and other breathing problems during sleep can put kids at risk for poorer performance in school, a new study confirms.

Parents, teachers, and health care professionals need to be aware of the potential effects of sleep-disordered breathing and be able to recognize the symptoms, Barbara Galland, who led the study, said in an email.

Galland, from the University of Otago, Dunedin, New Zealand, and her colleagues analyzed data pooled from 16 studies done in 12 countries, each including an average of about 550 children ages 5 to 17.

The studies looked at symptoms of sleep-disordered breathing, such as habitual snoring and sleep apnea (pauses in breathing while asleep), as well as students' grades as reported by their school or their parents.

The combined academic scores overall of students with breathing problems during sleep were roughly 12 percent lower than scores of students without sleep-disordered breathing, the researchers reported in the journal Pediatrics.

In particular, language arts scores were 12.3 percent lower, math scores were 13.1 percent lower, and science scores were 11.6 percent lower for the affected kids.

According to study published in 2009 in the journal Sleep, roughly one in every 100 elementary school children in the U.S. has sleep-disordered breathing.

"Although many studies find that the average achievement of children with sleep-disordered breathing remains in the range of typical children, children with sleep-disordered breathing may be more at risk for performing below this level," Galland said.

"That is, some children with sleep-disordered breathing may be performing less well on the tests. What we do not know is which children are more likely to do less well," she added.

The studies represented academic performance at one point in time, and "negative effects over time cannot be ruled out," the researchers wrote.

When sleep-disordered breathing is related to children's tonsils and adenoids, removing them might be helpful, the researchers said.

"For other children, jaw alignment may contribute and dental treatment is being developed to address this," Galland said. "Other health factors such as obesity can also contribute to sleep-disordered breathing, another reason for developing effective approaches to address this complex health issue."

More research is needed, she added, to understand which children are most at risk for academic difficulty associated with sleep disordered breathing and to figure out how they can be helped.