Enough sleep makes brilliant kids

Parents may be able to get by on little sleep from time to time, but shortchanging kids on slumber can turn their days into nightmares.

Studies show younger children who don't get enough sleep -- nine hours is considered optimum for elementary school children -- can suffer in school, are at higher risk for accidents and could even be mistakenly thought to have attention-deficit hyperactivity disorder (ADHD) because the symptoms of sleep deprivation closely mirror those of ADHD.

This is not a small problem, says Carl Hunt, director of the National Center on Sleep Disorders Research at the National Heart, Lung, and Blood Institute (NHLBI).

"All the evidence we have suggests that perhaps a third of children don't get the amount of sleep they need," he says, "and the price children pay for not getting enough sleep is an increased risk for accidents and problems in learning, mood and behavior."

Exacerbating the problem, Hunt says, is that the sleepiest children often don't seem sleepy at all.

"A major problem with children if they are sleep-deprived is that once they get up and get going, they don't act sleepy during the day and early evening. Instead, the sleep deprivation may have the opposite effect, and they may be overactive," he says. "Because they don't act sleepy, parents don't appreciate that the cause of their hyperactivity is sleep deprivation, but there is a clear association between lack of sleep and overactivity."

Recent studies confirm the additional risks of sleep deprivation.

In the March-April issue of Child Development, Israeli psychologist Avi Sadeh reported that among a group of elementary school children, as little as one extra hour of sleep a night significantly improved school performance.

Sadeh found those who had more sleep improved their performance on tests assessing attention span and memory, both of which are necessary for optimum school performance.

Those who lost an hour of their regular sleep showed no improvement on the memory and attention span tests, and on tests measuring reaction times performed significantly poorer than they had before they were sleep-deprived.

"This is the first evidence that really minor variations of sleep in children can have measurable effects on cognitive function," Sadeh says.

The playground can become a more dangerous place for tired children as well.

A recent Italian study of approximately 300 children under 14 who visited hospital, compared the sleep patterns of children on the days they were injured to their sleep patterns when they weren't hurt and found a link between lack of sleep and increased risk of injury.

Among the findings: Sleeping less than 10 hours a day was associated with an 86 per cent increase in risk for injury; and children between the ages of 3 and 5 who slept less than 10 hours a day seemed to have a significant increase of risk of injury, especially boys.