Sleep loss is taking a toll on our physical and emotional health, and on our nation's highways.
Elise G. hits the alarm at 5:30 a.m. to get her kids and herself up and ready. She's an elementary teacher in Marietta, Ga., with a seasonal business on the side. When a big holiday is coming up, she's typically burning the midnight oil most nights. On weekends, she says, "I've just got to catch up on my sleep."
Multiply her story about 30 million times, and you've got a snapshot of America's sleep situation.
For the past few years, the Sleep in America polls -- conducted on behalf of the National Sleep Foundation - have provided a snapshot of the nation's bedroom woes. Today, about 20% of Americans report that they get less than 6 hours of sleep on average, and the number of Americans that report that they get 8 hours of more has decreased.
"It's no secret that we live in a 24/7 society," says Carl Hunt, MD, director of the National Center on Sleep Disorders Research at the National Institutes of Health. "There are many more opportunities to do things other than sleep - 24-hour cable TV, the Internet, email, plus long work shifts."
Indeed, how we live is affecting how we sleep, says Meir Kryger, MD, director of the Sleep Disorders Centre at St. Boniface Hospital Research Centre at the University of Manitoba. "Often, our sleep deficit is related to too much caffeine, nicotine, alcohol. Often it's related to work - stress from work, putting in long hours at work, working night shifts, working on the home computer until the second we go to sleep."
Yet there's strong evidence that lost sleep is a serious matter. The Sleep in America polls and several large studies have linked sleep deficits with poor work performance, driving accidents, relationship problems, and mood problems like anger and depression.
"People just don't realize how important sleep is, and what the health consequences are of not getting a good night's sleep on a regular basis," Hunt tells WebMD. "Sleep is just as important for overall health as diet and exercise."
They also don't talk to their doctors about sleep problems, he adds. "They figure everybody's sleepy, and what can be done about it anyway. And doctors don't ask about it. Sleep disorders are severely under-diagnosed and under-treated."
The Science of Sleep
Over the past decade, researchers have learned much about the science of sleep, says Mark W. Mahowald, MD, a neurologist and director of the Minnesota Regional Sleep Disorders Center in Rochester.
There are nearly 100 identified sleep/wake disorders, Mahowald says. In a recent issue of the journal Nature, Mahowald outlined the latest scientific findings on these two familiar patterns:
Hypersomnia: This is sleep deprivation, or excessive daytime sleepiness without an obvious cause. This pattern "should be taken very seriously," Mahowald writes. The result is sleepiness, which results in impaired sustained attention, with adverse, occasionally disastrous consequences in the classroom, workplace, or the highways. It is likely that more than 100,000 crashes occur annually in the U.S. due to driving while drowsy, he adds.
The most common cause of hypersomnia is voluntary sleep deprivation done for social or economic reasons - like work or surfing the Internet, he notes. "We get 20% less sleep than previous generations, yet there is no evidence that earlier generations required more sleep - or that ours needs less," he writes.
Insomnia: This is the most common sleep complaint, says Mahowald. It is not defined by total sleep time but by trouble falling or staying asleep. It is the inability to obtain sleep that is sufficiently long or "good enough" to result in feeling rested or restored the following day. Depression has been linked as a cause of insomnia; however, for many people, untreated insomnia may be a risk factor for depression, he tells WebMD.
Many insomniacs may have a condition called hyperarousal - essentially, they're always on alert, which means they rarely can sleep, Mahowald explains. "There is overwhelming evidence that many who have insomnia have a constitutional predisposition to be hyperaroused 24 hours a day. They have trouble sleeping, then feel miserable during the day, fatigued, washed out, have trouble concentrating. But they are not sleepy. They never take naps, because the same thing happens - they can't sleep during the day."
Neurological scans show differences between the brains of insomniacs and non-insomniacs. There seems to be a genetic component to both hyperarousal and insomnia, Mahowald tells WebMD.
"They typically have a family history of insomnia. Many people have had it as long as they can remember, since childhood. It takes very little for them to get insomnia - a test the next day, an upcoming trip. They can get insomnia for what seems like very trivial reasons, but it's probably constitutional. They are very fragile sleepers because they are predisposed to developing insomnia."
The Effects of Lost Sleep
An NIH State-of-the-Science Conference focused on the public health issues of chronic insomnia - including the larger impact that is not often noticed. When children and the elderly (particularly nursing home residents) suffer from insomnia, parents and caregivers also suffer. Employers suffer when an insomniac's work performance is affected.
Most people need between seven and eight hours of sleep each night to feel refreshed and function optimally, says Hunt. "Obviously there's some variation, some people intrinsically need more sleep than others. A few people skip by successfully long-term getting less sleep - but that's a very small number."
If you're getting less sleep than your body needs, there can be serious consequences.
"There's recent evidence showing -- in men and women in several countries -- that chronic sleep deprivation increases risk of early death," Hunt tells WebMD. "Studies are showing that people who get less sleep are at greater risk for heart disease and heart attacks. And perhaps the hottest area of research has shown a link between chronic sleep deprivation and risk of overweight and obesity. These studies articulate the price society pays in not getting a good night's sleep."
The affect on our functional status was borne out in the 2005 Sleep in America survey. Over one-quarter of working adults - 28% -- said they had missed work, events and activities, or made errors at work because of sleep-related issues in the previous three months.
Laboratory studies have confirmed this impact on performance. In one small experiment, 16 young adults were allowed only five hours of sleep for seven nights. As the week wore on, the volunteers showed increasing difficulty performing tasks.
It's true, some people can get by just fine with less sleep. One study found that there are significant differences in impairment among sleep deprived volunteers - suggesting that vulnerability to sleep deficits varies greatly.
But for most people, getting less than six hours sleep translates into a bigger sleep debt than they may realize. Over a two-week period, missing out on the recommended eight hours of nightly sleep adds up to two full nights' sleep debt, one study found. If you're averaging only four hours a night, your brain reacts as though you haven't slept at all for three consecutive nights.
The most worrisome part: Many people are too tired to realize how sleep-deprived they are, experts say. But they have slower reaction time, weaker memory, and other thinking impairments.
The Dangers of Drowsiness
Sleep-deprived people often don't realize their vulnerability to sleepiness, and therein rests the self-denial, explains Joseph Kaplan, MD, co-director of the Sleep Disorders Center at the Mayo Clinic in Jacksonville, Fla.
"Sleepiness is governed by two processes - the amount of sleep you get and the circadian rhythm," he tells WebMD. "You can go a night without sleep, and be fairly alert the next morning. But as the circadian influence begins to have its impact, that's when you really feel it."
Kaplan says the most vulnerable times for sleepiness: 5 to 8 a.m. and 2 to 4 p.m. Most alert times: 10 a.m. to noon and 7 to 9 p.m. "Regardless how many hours you're awake, the sleepiest time occurs as the circadian night is ending," he says.
Night shift workers may be the hardest hit by sleep problems. They're less able to stay alert, they have decreased job performance, and they have more accidents. One study found that 20% of shift workers fall asleep during a single night shift compared to none during an afternoon or evening shift.
Several major disasters have been linked in part with too little sleep in the workplace: Three Mile Island, Chernobyl, and the Exxon Valdez.
Nearly one-third of all respondents to the 2008 Sleep in America poll reported that they have driven drowsy at least once per month during the past year. Of those who drive, more than one-third had nodded off or fallen asleep while driving a vehicle. And 2% had an accident or near accident due to drowsiness while driving.
"We are very concerned that shift workers are on the highway, at increased risk for car wrecks," says Barbara Phillips, MD, sleep clinic director at the University of Kentucky in Lexington. "Many are also in safety-sensitive positions, like health care workers and pilots."
Indeed, doctors, nurses, and other health professionals are especially vulnerable to the effects of sleep loss - and patient safety may suffer because of it. Studies on performance of sleep-deprived doctors have suggested that they may be prone to more errors on routine, repetitive tasks - and also on tasks that require close attention for long periods. However, those same studies show that, in times of crisis or unusual situations, doctors may be able to rise to the occasion and function well.
Sleep-deprived drivers are just as dangerous as drunk drivers, Kaplan says. In one study, people who drove after being awake for 17 to 19 hours performed worse than those who had a blood alcohol level of .05%. (A blood alcohol level of .08% is considered legally intoxicated in many states.)
Kaplan is a big advocate of napping. "Fifteen or 20 minutes may be all you need," he tells WebMD. "One strategy for truck drivers is to take a full cup of coffee, then immediately follow with a 30-minute nap. Caffeine doesn't take effect for about 30 minutes, so you get the benefit of both."
Tips on Getting a Good Night's Sleep
If you're having trouble sleeping, there are many solutions, say sleep experts. Turning off the computer or TV earlier is one simple solution. But other lifestyle issues might be hindering sleep. Sleep specialists advise following , including cutting back on caffeine and alcohol. They also advise developing a calming ritual before bedtime - one that helps you break from the day's tensions, and doesn't involve eating, exercise, or watching TV.
Beyond that, sleep medications and behavioral treatments can be effective treatment for chronic insomnia. Behavioral therapy involves changing your negative thoughts and expectations that may worsen your insomnia. Medications can help you break the pattern of insomnia.
"We now have very effective sleep medications," Mahowald tells WebMD. "Many patients have taken these sleep medications for decades without any dependence or tolerance problems. If they need the drugs, they take the drugs. If they don't need them, they don't take them."
"With medication and possibly behavioral therapy, we can make insomnia decidedly better in just a few weeks," he says.
More commonly, chronic insomnia is a conditioned response - a pattern of fearful thinking that develops after a few nights of restless sleep, Mahowald says. "There's worry that it will happen again, which becomes a self-fulfilling prophecy."
By making sure you get enough sleep, you're improving your quality of life. "Sleep deprivation has a cumulative effect, escalating over time in fatigue, sleepiness, stress, mood problems," Kaplan tells WebMD.
"The good news is, although we're learning that sleep disorders are more common than we realized, there are effective treatments, ways to improve symptoms and quality of life for anyone who has a sleeping disorder," says Hunt.