The interrupted sleep, snoring, and nighttime breathing troubles associated with sleep apnea isn't just affecting adults — kids can get the condition, too, experts say.

In fact, sleep apnea has recently been linked to lowered childhood IQ scores and an increase in learning problems. The condition is thought to be caused by a relaxation during sleep of soft tissue in the back of the throat, causing airway obstruction and frequent nighttime awakenings.

HOW MANY CHILDREN ARE AFFECTED?

"There's no good data," said Daniel S. Lewin, director of pediatric behavioral sleep medicine at the Children's National Medical Center in Washington, D.C. But he believes that about 2 percent to 3 percent of youngsters age 2-and-a-half to 5 may have obstructive sleep apnea.

In up to 75 percent of cases, the condition can be cured by removal of either the tonsils or adenoids, the experts point out.

However, as the number of overweight or obese children increases, the number of pediatric sleep apnea cases may also rise, Lewin said. Fat deposits in the upper airway can contribute to breathing obstruction, he said.

And that could mean more trouble in school for affected children, added Dr. Ann Halbower, medical director of the pediatric sleep disorders program at the Johns Hopkins University Children's Center in Baltimore.

Halbower evaluated 31 children - ages 6 to 16 - 19 of whom had untreated severe sleep apnea. MRI scans showed that those children with sleep apnea had changes in two key brain regions associated with higher mental function - the hippocampus and the right frontal cortex.

The children with apnea also had altered ratios of three brain chemicals possibly reflecting brain damage.

Those with apnea had lower average IQ test scores. "The control kids averaged 100 (considered average), the apnea kids 85," Halbower said. "That's a huge difference. That's not like some of the other studies showing significant difference in normal ranges."

"We confirmed what others have shown," said Halbower of her study, published in the journal Public Library of Science Medicine.

Whether the damage is reversible or not is not known, Halbower said. She's continuing to study the problem.

Meanwhile, parents need to be alert to any symptoms of apnea in their children and seek help immediately, Halbower said.

What should parents look for? "Signs of disturbed breathing at night, including snoring, gasping, severe sweating, labored breathing, trouble sleeping at night," she said. "If they notice that, they should report it to their doctor and ask to have the child checked."

Other worrisome red flags, said Lewin, include the frequent need for a young child, under age 10, to sleep in. "Children who fall asleep other times other than their nap" should also be checked out, he said. "They might be sleep deprived or possibly have apnea."

Luckily, for most kids, a tonsillectomy or adenoidectomy can alleviate the problem. "If they can't get a surgical treatment, they should be on continuous positive airway pressure — a mask they can wear over the nose to give them air to breathe," Halbower said.

"In general, taking out the tonsils and adenoids cures about 75 percent of kids (with apnea)," Lewin said. For the others, the airway pressure can help, he agreed.

Whether they have sleep apnea or not, too many American children are not getting the right amount of shut-eye each night, new research shows.

For example, one recent study of 169 1 to 5-year-olds, conducted by researchers at Brown University Medical School, found that most didn't get the 12 to 15 hours of sleep recommended for this age group.

The older children in the study got less than 9.5 hours of sleep a day, the researchers found, while infants and toddlers got 10-and-a-half to 11 hours of slumber daily.

LEARN MORE:

www.ninds.nih.gov, the U.S. National Institute of Neurological Disorders and Stroke has more information about sleep apnea.