How Did You Sleep Last Night? (cont.)

"Some people are very sleepy early in the evening, and by 8:30 p.m. or 9 p.m., they have a lot of trouble staying awake," says Kryger. "So they'll go to sleep and frequently wake up at 3 or 4 in the morning." In our culture, Kryger says, people may not think of these larks as having a sleep problem -- they often exercise at the crack of dawn and arrive at their office long before their co-workers to get a fast start on a productive workday.

By contrast, those who tend to stay up long past midnight have plenty of trouble getting up in the morning and typically arrive at the office late the next morning; they often call their doctor seeking help for staying alert through the day.

Although our sleep-wake cycles appear to be written into the genes, don't despair if your body clock is creating chaos in your life. Environment and personality also play important roles in influencing your sleep-wake schedules, says Herman, director of the Sleep Disorders Center at Children's Medical Center in Dallas.

"Light is the strongest cue that the body uses to determine when to go to sleep and when to get up," says Ancoli-Israel, director of the Sleep Disorders Clinic at the Veterans Affairs San Diego Healthcare System. So people whose natural tendency is to sleep late in the morning may benefit from bright light exposure at daybreak. And if sunlight isn't readily available, there are bright-light boxes that can be purchased.

Rude Awakenings With Apnea

If you're a woman, female hormones might provide some protection against obstructive sleep apnea, a condition in which obstruction of the airway occurs during sleep. Symptoms include loud snoring and repeated awakenings which are associated with excessive daytime sleepiness.

Apnea is increasingly being recognized as a common sleep disorder (affecting about 12 million Americans) it's about twice as common in men as it is in women. But in the postmenopausal years when levels of female hormones subside dramatically, says Kryger, new cases of sleep apnea are about equal in men and women.

If you have sleep apnea, it's not something you can afford to ignore. "Sleep apnea can lead to high blood pressure and other medical problems," says Kryger. "Some data show that people with sleep apnea may develop insulin resistance, which could be a precursor to the development of diabetes."

CPAP (continuous positive airway pressure) is an effective sleep apnea treatment, in which a device worn at night gently propels air through the nasal passages, keeping the airway open during the night. "It's very effective if people use it, but because it isn't very comfortable, compliance isn't as good as it should be," says Ascoli-Israel. Weight loss can relieve the severity of the disease in many patients and certain sleep positions can as well.

Optimal sleeping positions may be important in resolving problems associated with other health conditions as well. With gastroesophageal reflux disease (GERD), in which people experience heartburn and regurgitation at night, "we commonly suggest that people raise the head of their bed three to four inches using some wooden blocks, so they're sleeping on an incline," says Zammit.

People with allergies, particularly when accompanied by postnasal drip and congestion, may find that their symptoms worsen when they're sleeping on their back, and thus a change in position may be just what the doctor ordered.

I Could Have Walked All Night

Although it's a common belief that sleepwalkers are acting out their dreams, there's no evidence of that. Instead, the tendency toward middle-of-the-night marches through the house -- and sometimes through the neighborhood -- may be imprinted in the genes, and thus sleepwalking often runs in families. The medical literature is replete with cases of families of sleepwalkers who literally bump into each other during the night.

"Sleepwalkers can also carry out very complicated behaviors," says Ancoli-Israel. "Some have gotten into and driven their car, even though they're sleeping at the time."

During periods of stress -- when the pressures of work and family become crushing, or when the threat of job layoffs or tough economic times loom ominously in the back of their minds -- adult sleepwalkers may experience a worsening of their problem. Nocturnal sleep-related eating disorder (NSRED), a little understood problem in which sleepers stroll into the kitchen and gobble up sugar-rich and high-fat foods, may affect as many as 4 million Americans, and appears to be stress-related as well.

Even if you're not a sleepwalker, stress can make it more difficult for you to fall asleep and stay asleep. A survey by the Better Sleep Council found that 51% of Americans say that stress disrupts their snoozing.

When should you seek help for a sleep problem? "At the point where it starts interfering with your daytime functioning," advises Ancoli-Israel. "A good night's sleep is very important." And if your physician thinks that sleeping pills might be helpful, the newer medications (such as Ambien and Sonata) are safer than the sleeping aids of the past.

Published April 1, 2004.

Medically updated March 18, 2005.

SOURCES: Sonia Ancoli-Israel, PhD, professor of psychiatry, University of California San Diego School of Medicine, San Diego. John Herman, PhD, associate professor, psychiatry, University of Texas Southwestern Medical Center, Dallas. Meir Kryger, MD, director, Sleep Disorders Centre, St. Boniface Hospital Research Centre, Manitoba, Winnipeg, Canada. Gary Zammit, PhD, director, Sleep Disorders Institute, St. Luke's-Roosevelt Hospital, New York City.

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