ADOLESCENTS AND SLEEP

A Summary of Sleep Needs, Patterns, and Difficulties of Adolescents

Young people today lead busy lives -- school, work, family, friends, social events, sports, and other activities take up many hours of the day and evening. When push comes to shove for teens, a good night’s sleep is often the first thing to go. But a growing body of research indicates that adolescents are particularly vulnerable to sleep difficulties, and they risk a range of problems when they shortchange sleep.

A recent meeting gathered scientists, health professionals, teachers, school board members, parents, and young people themselves to talk about the dangers of chronic sleep loss for young people. The workshop discussions are summarized in a new report Sleep Needs, Patterns, and Difficulties of Adolescents, published by the Institute of Medicine and the National Research Council. Here are some of the things sleep researchers had to say.

How much is enough? Some studies have found that teens need more sleep -- not less – as they go through adolescence. Even with more than 9 hours of sleep a night these teens struggled with drowsiness, especially early in the day. Despite the evidence pointing to a need for more sleep, surveys of students show that they report later and later bedtimes, but must rise early for school. High school starting times have become earlier in recent years, with many beginning at 7:30 a.m. due largely to school bus schedules. Thus, many teens report sleeping 7.5 hours or less on weeknights rather than the 8 or 9 hours they need to be alert during the day.

“Sleep Debt” and its consequences. Lost sleep accumulates over time; the more “sleep debt” an individual incurs, the greater the negative consequences. The effects of chronic sleep loss are more than just fatigue. New findings point to a significant change in the learning curve from lack of sleep. With 8 hours of sleep a night, subjects get better every day at an assigned task. With 6 hours of sleep, that learning curve is gone, and at 4 hours of sleep the negative impact on sleep is even more apparent.

Consequences of insufficient sleep in adolescents include missed school, sleepiness, tiredness and decreased motivation, and difficulties with self-control of attention, emotion and behavior. In fact, research suggests that sleep deprivation has a greater effect when both cognitive and emotional factors come into play, as they do so frequently as teens struggle to gain mastery of their emotions and impulses.

The dangers of drowsy driving. Young people may feel adapted to being tired but performance tests indicate otherwise, as laboratory research shows. With 8 hours sleep, individuals are consistently alert. As the amount of sleep drops to 6 hours, the study participants experience what researchers call “micro-sleeps” – lapses of wakefulness of mere seconds. While these lapses may not be serious in some situations, a one-second lapse in reaction time while driving a car at 60 miles an hour translates into 88 feet. The National Highway Safety Administration estimates that more than 100,000 crashes annually are caused by drivers falling asleep. Fatalities from such crashes take the lives of more than 1,500 young people each year.

What contributes to teen sleep difficulties? Two intrinsic processes influence sleep. One is the biological timing system – the circadian rhythms of approximately 24 hours that influence when and how much we sleep. The second is the sleep-wake homeostasis system that tallies the balance of sleeping and waking. Some research suggests that the sleep-wake cycle shifts during adolescence. As a result, teenagers have a natural tendency to fall asleep later and wake up later.

Research is continuing to study the influence of the biological process on teen sleep. But experts emphasize that other psychosocial and environmental conditions make it easier for adolescents to delay bedtimes. Sports, homework, jobs, socializing with friends all play a role. And the availability of television, CDs, and computers, which many young people have in their rooms and use without effective parental controls, also has a bearing on sleep habits.

Sleeping in on weekends is one way that teens pay back some of their sleep debt. But irregular sleep schedules also pose problems. Delaying weekend bedtimes and rising times for several hours can disrupt the normal sleep cycle much the way jet lag can affect long-distance travelers. Despite this concern, some researchers say allowing adolescents to sleep an hour or so later on weekends can help them repay the “sleep debt” run up during the week.

Sleep disorders. Adolescents also suffer from a variety of sleep disorders. In some cases, such as narcolepsy – sudden and uncontrollable attacks of deep sleep -- the symptoms may differ from those in adults. In a study of children between the ages of 10 and 13 with narcolepsy, only 1 out of 15 actually exhibited the classic symptoms. Disturbed sleep is also related to other disorders such as depression. Teens with serious sleep problems should be seen by a doctor or sleep specialist. Smoking, which has increased among teens, may play a role in sleep loss. Surveys have shown that cigarette smokers have increased problems falling asleep and staying asleep. They also have higher consumption of caffeine than non-smokers.

Restructuring the day. Some school districts have considered changes in school start times in response to concerns about problem sleepiness in students. Early findings from studies of high schools in Minneapolis and Edina, a suburb, indicate a majority of teachers reported that a greater number of their students were more alert during the first two school periods than they had been with an earlier start time. Slightly more than half said they saw fewer students sleeping at their desks. In Minneapolis, teachers were evenly divided about whether student behavior improved. In contrast, Edina teachers indicated markedly improved student behavior. In Minneapolis, both teachers and students reported a drop in students involved in extracurricular activities; later schedules also posed difficulties for some students who worked after school.

Later school starting times are not a panacea for adolescent sleep problems, nor do they work well for all students or all school districts. Any change in educational systems requires gathering all stakeholders to review the data and debate the range of possible options.

Many teens work after school, and this, too, can impinge on sleep schedules. While working can have positive benefits, research shows that working more than 20 hours a week during the school year is associated with such problems as substance abuse, limited time spent with families, and insufficient sleep and exercise.

The importance of sleep. Researchers noted that social and behavioral influences play a critical role in sleep habits and need to be recognized. In the laboratory or another setting, such as a camping trip, where television, phones, video games, socializing, and other distractions are absent, adolescents are more likely to go to sleep earlier. But returning to every day life and their own habits, they revert to patterns that lead to inadequate sleep. Parents, teachers, health professionals, and teens themselves should get the facts about chronic sleep loss and adopt healthier sleep habits.