Sleep specialists say there are two main types of insomnia in kids. Sleep-onset-association insomnia is more likely to be seen in children younger than 5 and usually involves interruptions in sleep during the night. All children naturally wake ten to 12 times during the night and most roll over and fall back asleep, explains Daniel Glaze, M.D., medical director of Texas Children's Hospital Sleep Center, in Houston. But a child who's used to having a parent help him fall asleep could cry out until she appears.
Limit-setting insomnia, on the other hand, is mostly seen in children older than 5, who are able to get out of bed. A child with this issue makes prolonged bedtime curtain calls -- asking for water, claiming there's a scary monster under the bed, or suddenly needing an explanation of what happens when the toilet flushes. When his parent gets him a drink or tries to discuss his fears, it only reinforces his behavior.
Spotting Side Effects
When children don't get enough sleep (12 to 14 hours total for toddlers; 11 to 13 hours for preschoolers) they can have a drop in IQ points equivalent to what's typically seen in a child who has lead poisoning, according to a study from the University of Virginia, in Charlottesville. And if sleep problems persist for many years, they can impair a child's ability to complete tasks that require a higher level of thinking later in life, according to researchers at the University of Colorado, in Boulder, who tracked the sleep habits of twins.
It's not exactly clear why a child's brain is affected when she loses sleep, but studies suggest that a sleep deficit causes neurons to lose their ability to adapt, says Judith Owens, M.D., a Parents advisor and director of sleep medicine at Children's National Medical Center, in Washington, D.C. In other words, a tired brain becomes incapable of forming the connections needed to embed new knowledge, memories, and skills. One study found that elementary-school students who had missed just one hour of sleep three nights in a row performed two years below their actual grade level on academic tests.
What's more, a growing body of evidence is turning up proof that insufficient sleep is one of the culprits behind the childhood obesity epidemic, most likely because sleep plays a crucial role in regulating the hormones that determine appetite. In one large Canadian study, children between the ages of 2 and 6 who got less than ten hours of shut-eye a night were more than four times more likely to be overweight or obese than kids who consistently got 11 hours of sleep a night. Research in adults also suggests that there may be long-term cardiovascular risks from a lack of sleep, which Dr. Owens says could mean similar trouble in children.
The number of children at risk for these side effects is probably greater than the estimated 20 to 30 percent of kids suffering from insomnia, says Sarah Honaker, Ph.D., a behavioral sleep specialist at the University of Louisville School of Medicine. After all, a parent is better able to recognize when she's tired than when her own child is tired. And fatigued kids often become hyperactive, making it even harder to recognize the real problem.