You're at a point in life when you should be getting a good night’s sleep. In fact, you need it to function at work the next day. Nonetheless, its 4 a.m., and you're wide awake--for the umpteenth night in a row. Sound familiar?
Join the sleepless crowd. More than 60 percent of adult Americans experience a sleep problem at least a few nights a week. And it can get worse with each year. After age 50, medical conditions such as back pain, arthritis, and bladder problems begin to take their toll on sleep. Also, specific sleep disorders, such as restless legs and sleep apnea, become more common. But even more fundamental than these physical issues are changes in the very nature of sleep.
Why Do We Sleep?
Scientists are still in the dark about this question, although various theories have held sway over the years, including both the ebb and flow of hormones and a buildup of carbon dioxide in the body. The latest theory is that sleep restores energy to the brain’s nerve cells, according to Andrew A. Monjan, Ph.D., chief of the National Institute on Aging’s Neurobiology of Aging branch. In other words, sleep is hardly a dormant state; while you're snoozing away, your brain is busy recharging.
To give the brain a chance to restore itself, the body’s systems first must get it ready to go to sleep. At about 6 each evening, the pineal gland begins to secrete melatonin, which will gradually build up over the next few hours. At the same time, levels of the molecule adenosine, a breakdown byproduct of normal metabolism, begin to rise. “Once adenosine reaches a certain level, you activate cells that end up producing sleep,” says David White, M.D., professor of sleep medicine at Harvard Medical School.
While the process is more complicated than this, you get the idea. After a round of shuteye, you feel mentally and physically renewed. Skimp on sleep however, and you're likely to drag during the day. Researchers at the University of Pennsylvania in Philadelphia restricted participants in a recent study to four, or six, or eight hours of sleep each night for 14 nights. By the sixth day, those allowed six hours--an average night’s sleep for many people--were roughly as alert as those who had gone without any sleep for one night. And that’s not very alert.
If chronic sleep deficit becomes your norm, you may be able to execute low-level mental chores such as figuring the tip on your lunch bill--but it may take you longer than it would if you were rested. And you may as well say good night to performing several work tasks concurrently, absorbing new information, or making sound judgment calls, especially in a crisis. All told, “Anything that’s not routine becomes difficult if you're tired,” Monjan says.
The Changing Pattern of Sleep
Maybe you've heard that you need less sleep as you get older. That’s just wishful thinking. The need for sleep doesn't diminish in midlife or even in late life. You still require the same amount you did when you were 25 or 30 years old--about eight hours a night.
“Yet the pattern of sleep does change as we age,” says Sonia Ancoli-Israel, Ph.D., director of the sleep disorders clinic at the Veterans Affairs San Diego Healthcare System in California. You may find yourself getting sleepy earlier in the evening, say 8 p.m. instead of 10 p.m., and routinely waking at 4 a.m. instead of 6 a.m. These kinds of changes result from natural shifts in circadian rhythm, the biologic clock all humans carry within themselves that is based on an approximate 24-hour cycle.
However, if you continue to go to bed at 10 p.m., which has been your routine lights-out time for decades, you'll still wake at 4 a.m. “That’s morning to your body,” Ancoli-Israel says. But, unfortunately, you've only slept for six hours.
How we sleep changes in other ways as we age. During sleep, people go through four distinct phases: Stages 1 and 2, the lightest stages, are followed by stages 3 and 4, also called slow-wave sleep, the deepest and perhaps most restorative phases. These latter two stages occur just before REM (rapid eye movement) sleep, when dreaming occurs. For reasons not yet fully understood, getting older brings with it a change in the proportion of various stages of sleep. Infants and children snooze away as much as 20 percent of the night in stages 3 and 4. But studies show that older adults spend most of the night slumbering in the lightest stages; deeper stages 3 and 4 sleep may occupy only 5 percent of the night.
At the same time that sleep patterns change, the incidence of sleep disorders increases. The years after 50 are the prime target for a condition called sleep apnea, a slumber if there ever was one. In sleep apnea, which affects about 4 percent of middle-aged men and 2 percent of middle-aged women, tissue in the esophagus momentarily obstructs the airway, causing breathing to stop--sometimes briefly, sometimes for 10 seconds or longer. When oxygen levels plummet, the person wakes up, but perhaps not sufficiently to realize what has happened. According to the National Institutes of Health, someone with sleep apnea may experience as many as 20 to 30 or more involuntary breathing pauses each hour.
Two additional disorders that can interfere with getting a good night’s sleep are restless leg syndrome (RLS) and periodic limb movement disorder (PLMD). In RLS, unpleasant creeping, crawling, and tingling sensations produce the irresistible urge to move the legs, especially at night when you're lying down waiting to fall asleep. PLMD involves involuntarily kicking several times a night that causes you to hover in lighter stages or wake up. “The majority of patients with RLS also have PLMD,” says Andrew L. Chesson, M.D., Jr., director of the Sleep Disorders Center and professor of neurobiology at Louisiana State University Health Sciences Center in Shreveport.
The exact causes of the two disorders are still unknown. Sometimes RLS is inherited, and some cases have been associated with nerve damage in the legs as the result of diabetes. A number of scientists believe that the mechanism underlying PLMD involves a problem in the nervous system. Both disorders can be treated with drugs. Other sleep robbers include pain from arthritis, heartburn, low back pain, and medications with side effects that interfere with sleep.
“You know you have a problem if you can't sleep when you want to or you're your bedmate tells you your sleep is disrupted,” says David N. Neubauer, M.D., associate director of the Johns Hopkins Sleep Disorders Center in Baltimore.
If any of these symptoms lasts more than a month and interferes with the way you feel and function during the day, seek help from your doctor. The solution may be as simple as switching to a medication that doesn't cause sleeplessness or treating a medical condition that does. For more complex problems, ask your doctor to recommend a sleep specialist. You don't have to put up with sleepless nights because that’s just the way it is. “By itself, getting older is not a cause of insomnia,” Monjan says.
Snooze News You Can Use. In addition to consulting your doctor, here are some other strategies that can help put you on the road to dreamland.
Darken your bedroom. Invest in room-darkening bedroom shades that block moonlight and early morning sun. “As much we need light during the day, we need darkness at night,” says Sonia Ancoli-Israel, Ph.D., director of the sleep disorders clinic at the Veterans Affairs San Diego Health Care System in California. If you get up during the night to go to the bathroom, she suggests using a nightlight to show the way rather than turning on a bright overhead light.
Reserve your bed for sleeping. Move the television set into another room and, if possible, limit bedtime reading to a chair next to your bed. Otherwise, you send your body the message that the bed is a place to stay awake. If you can't fall asleep after 15 minutes, leave the bedroom and do something boring until you feel tired.
Avoid caffeine and alcohol. Scientists believe that caffeine blocks the action of adenosine, the organic compound that promotes sleep, and stimulates brain cells to work overtime. If sleep is really a problem, Ancoli-Israel suggests avoiding any caffeine after lunchtime. Besides obvious sources, such as caffeinated coffee (103 mg caffeine in 6 ounces), tea (36 mg in 6 ounces) and cola beverages (49 mg in 12 ounces), try to steer clear of hidden caffeine in foods like coffee-flavored yogurt (44.5 mg in 8 ounces) and chocolate (6 mg in 1 ounce).
As for alcohol, you may be able to get away with having a glass of wine with dinner and still sleep well. But if you're having trouble, do without anything alcoholic for a few weeks to see if it makes a difference. As for nightcaps, forget them. Alcohol will make you drowsy initially, then cause you to wake hours later.
Grab a nap--maybe. For some people, a short mid-afternoon nap can make all the difference to the rest of the day, but for others, it’s the recipe for lost sleep at night. Certainly, people suffering from insomnia should avoid naps. If you're among those who take some time to doze off during the day, don't sleep too long; 15 to 20 minutes should be about enough.
Exercise. “Exercise helps you sleep longer and fall asleep faster,” says Abby King, Ph.D., of Stanford University School of Medicine in California. King is the lead researcher of a study on the relationship between exercise and sleep. The study randomly assigned 43 men and women over age 50 to exercise moderately (such as a brisk walk before dinner) for 30 to 40 minutes four days a week or to do nothing for four months. At the end of that time, she found that those who exercised generally slept an hour longer each night and also could fall asleep more quickly.
Get some afternoon light. If you don't want to hit the hay just as the dinner dishes have been cleared, spend time outdoors in the afternoon. If you're stuck in your office, take a break by going for a midafternoon walk. This can help turn back your circadian clock and counteract the natural aged-related tendency to fall asleep earlier in the evening and wake up earlier in the morning. If that doesn't work, you might consider a light box. For more information on light boxes, log on the Web site of the Circadian Lighting Association (www.claorg.org). Make a habit of sitting in front of it for a couple of hours in the evening while you read or watch television. Exposure to this kind of light also helps shift your internal clock.
Eat lightly at night. For reasons that are still unclear, a sizable meal an hour or two before bedtime can interfere with sound sleep. So if you eat dinner after 8 p.m., try to make it a light meal.
Drugs that Can Sap Your Sleep
If you take any of the following drugs and you have trouble sleeping, your medication may be to blame. Talk to your doctor about switching to another medication or changing the dose.
Beta blockers (to treat high blood pressure and relieve angina)
Thyroid medication (used when the thyroid gland doesn't produce enough hormone)
Bronchodilators (to prevent or treat symptoms of asthma, chronic bronchitis, and emphysema) and corticosteroids (to decrease the number and severity of asthma attacks)
To Sleep Like a Log, Log on to These Sites
For more information on getting a good night’s sleep:
--The National Sleep Foundation at www.sleepfoundation.org.
--American Academy of Sleep Medicine at www.aasmnet.org.
--National Center on Sleep Disorders Research, www.nhlbi.nih.gov/about/ncsdr.