"These findings have implications for how we understand attention problems in kids," said lead author Gahan Fallone, PhD, associate professor at the Forest Institute of Professional Psychology in Springfield, Mo. "The children in our study were functioning well at school prior to the restricted sleep schedule. It's likely that other kids who are physiologically or psychologically at risk for learning or attention problems could be even more vulnerable to the negative effects of inadequate sleep."
Dr. Fallone spoke today at the American Medical Association's 24th annual Science Reporters Conference in Washington, D.C.
In the study, 74 healthy, academically successful children between the ages of 6 and 12 were monitored for a three-week period. During the first week of the study, they slept their normal amount. For the second two weeks, they went to bed a little earlier one week and much later than normal the other. Their teachers rated their academic performance and behavior at the end of each week. Results showed significantly lower ratings for academic performance and attention during the week that they slept fewer hours, despite the fact that teachers were not told which sleep schedule the kids were on.
To make sure the children actually slept their assigned number of hours at home, they kept sleep diaries, wore activity-monitoring devices and made bedtime and rise time phone calls to the E.P. Bradley Hospital Chronobiology and Sleep Research Laboratory in Providence, R.I., where the study was conducted. "Most of the children also came to the lab each weekend for overnight sleep recording and assessment of daytime sleepiness with polysomnography," Dr. Fallone said.
It's clear from previous research that sleep is a precious commodity for schoolchildren. "There's a pretty steady decline in the amount of sleep kids get once they start school, and it's scary to look at how little sleep kids actually get once they become teenagers," Dr. Fallone said.
This pattern likely holds true for children who have been diagnosed with ADHD as well. According to Fallone, who is a clinical psychologist, "If we don't ask about sleep and try to optimize sleep patterns in kids with attention problems and academic difficulty, then we aren't doing our job." Stimulants, the most frequently prescribed class of medication for attention problems, may make it more difficult for some children to get to sleep at night, he said. While stimulants often are helpful for children, "our results suggest that getting less sleep at night could work against the therapeutic action of the medication and minimize the benefits at school. Increasing medication under these circumstances could actually make things worse."
Dr. Fallone is investigating sleep patterns and sleepiness in children with ADHD, but results in the current report indicate that, even among well-functioning kids, staying up late can significantly affect attention and performance in school. The message for parents is clear, Dr. Fallone said. "If our goal is to set kids up for success at school, then getting them to bed on time should be as important as getting them to school on time."
He notes that parents and kids can easily get caught up in a multitude of after-school and weekend activities that ultimately erode sleep time. "Parents have to make tough choices and set limits to protect sleep time, and as a society we need to be more supportive of such attitudes," Dr. Fallone said. "My advice for parents is to maintain a consistent emphasis on the importance of sleep and not to back off from enforcing bedtimes with kids, whether it's on school nights or weekend nights. Know when your kids are going to sleep and how they're sleeping during the night. If your child is having persistent difficulty with sleep, then talk to your doctor and get help."