When Sleep Leaves You Tired
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By MELINDA BECK
Ask readers of this newspaper if they're getting adequate sleep, and many would probably say "Ha!"
Twenty percent of Americans sleep less than six hours a night, and nearly one-third have lost sleep worrying about financial concerns, according to the National Sleep Foundation, which recommends that adults get seven to nine hours. "Our society thinks sleep is for slackers," says Darrel Drobnich, the organization's chief program officer.
But all that lost sleep is taking an insidious toll. Chronic, inadequate sleep raises the risk of cardiovascular disease, depression, diabetes and obesity. It impairs cognitive function, memory and the immune system and causes more than 100,000 motor-vehicle accidents a year. Sleep deprivation also changes the body's metabolism, making people eat more and feel less satisfied.
Studies presented at the American Association of Sleep Medicine's annual meeting in Seattle this week also found that inadequate sleep is associated with lower GPAs among college students and with elevated levels of visfatin, a hormone secreted by belly fat that is associated with insulin resistance.
What many people don't realize is that even if they log respectable time in bed (known as TIB among sleep researchers), they may be getting poor-quality sleep, with not enough of the restorative phases. REM, the Rapid Eye Movement phase in which dreaming occurs, is crucial for consolidating memories, learning, creativity, problem-solving and emotional balance. Deep, or slow-wave sleep, when the body secretes human growth hormone, is critical for development and physical repair. Both REM and deep sleep decline with age and are highly vulnerable to disruptions, from caffeine and alcohol to anxiety and a variety of sleep disorders.
One tip-off that you haven't gotten enough restorative sleep is trouble waking up and excessive daytime sleepiness (a condition known as EDS). "People say, 'Oh, I don't have a sleep problem. I can fall asleep anywhere, anytime' -- but that means you are excessively sleepy," says Charles Czeisler, a professor of sleep medicine at Harvard Medical School.
Other symptoms of sleep deprivation include mood changes, difficulty focusing or remembering and a chronic need for caffeine, which can then create a vicious circle of dependence and disruption. That would be me.
Finding out what's going on in your sleep generally requires spending the night in a professional sleep lab hooked up to lots of wires and monitors. But I've been testing a new home-sleep monitor called the Zeo Personal Sleep Coach that lets people track their sleep patterns nightly in their own bedrooms.
You sleep wearing a soft headband with sensors that monitor your brain waves and send signals wirelessly to a device that looks like a sleek clock radio. It displays whether you are awake or in light sleep, deep sleep, or REM sleep, in real time, all through the night.
"If you can measure it, you can manage it," says Stephan Fabregas, one of two recent Brown University graduates who invented the Zeo because they were looking for a way to wake up feeling less groggy after late nights.
Of course, not everyone needs a fancy gadget to tell them whether they are sleeping properly. But I was stunned by my results: The Zeo showed that I woke up numerous times and was awake for long stretches of the night, without having any recollection. (Perception of time is often distorted at night -- many people with insomnia actually sleep more than they think they do.) Even though I was in bed for six or seven hours each night, I was averaging only about four hours of real sleep and very little REM or deep sleep. No wonder I feel so tired!
The Zeo stores the information on a memory card you can upload to a Web site, which helps track your sleep patterns and sends daily coaching tips for getting better sleep. The $399 device comes with six months of daily email coaching, which can be extended at a cost of $99 for each additional six months. (Currently, it's available only online at www.myzeo.com.)
To help you keep track of your sleep, the Zeo also gives you a "ZQ" score every morning, based on the quantity and quality of your sleep the night before. There's no ideal ZQ -- you're comparing your own score from night to night. But the average for people in their 20s is 86; for those in their 40s, it is 74; and for those in their 50s, it is 67, since sleep quality declines with age.
My ZQs bounced from the 40s to a dismal 15 the first week. Switching to decaf after 3 p.m. and making an effort to get to bed earlier helped me bring my score into the 50s the second week. ("Having caffeine even first thing in the morning can induce changes in brain activity during sleep," says Kenneth Wright, director of the Sleep and Chronobiology Lab at the University of Colorado at Boulder and one of Zeo's scientific advisers.) I also noticed that the nights when I had the longest stretches of wakefulness were those when my column was due -- probably a sign that I was still thinking about it long after turning in.
Everybody's sleep and sleep disruptors are different. Todd Johnson, a 40-year-old border-patrol agent in Caribou, Maine, and one of ZEO's early testers, found that reading before he went to bed helped reduce his wake time and bring his ZQ from the 20s into the 60s. "You can try something that night and see the results in the morning," he says. Another early tester, Tim Guirl, who teaches at a community college in Seattle, found that he had more restorative sleep if he didn't exercise too close to bedtime and eliminated a large late-night snack.
Other recommendations from Zeo include reducing noise, light and disruptive influences like pets in the bedroom; having a "power-down" hour before bedtime with no email, no Internet use, no cellphones and no BlackBerrys; and keeping a consistent sleep schedule. And if you find yourself awake and worrying, Zeo recommends getting out of bed and writing down what you're thinking about in a "worry journal."
Zeo says its brain-wave results are similar to those from professional sleep labs -- but only about 140 people have tested it so far. And the Zeo isn't designed to diagnose actual sleep disorders, which plague an estimated 70 million Americans -- you need to see a doctor for that.
To see if something besides drinking coffee and thinking great thoughts was affecting my sleep, I underwent a sleep study at the Sleep Health Center connected with Brigham and Women's Hospital in Brighton, Mass. A polysomnography, as such tests are called, measures brain waves like the Zeo, but also heart rate, respiratory rate, oxygen saturation, body positions and movements. It took about 45 minutes to have all of the sensors and wires attached -- and then a little longer to get comfortable enough to sleep.
To my surprise, the study found that I had a fairly severe case of Periodic Limb Movements, episodes of involuntary muscle movements in the night. About 10% of adults have PLMs. Many don't even notice; sleep partners are often bothered more than the sleepers themselves. But PLMs can be very disruptive if they are accompanied by arousals from sleep. I was averaging 42 arousals per hour. According to David White, another Harvard sleep physician who prescribed the study for me, PLMs can be due to an iron deficiency or medication side effects, and they are often related to "restless-leg syndrome," which causes an irresistible urge to move the legs, day or night. Medications like Requip can minimize the movements; I'm going to give them a try.
The study also showed I had some obstructive sleep apnea, in which the airway narrows, especially when the muscles relax in sleep. People with OSA stop breathing momentarily until a lack of oxygen alerts the brain, which wakes them up with a gasp. These mini arousals can occur as often as 70 times an hour, leaving the sufferer exhausted and at risk for heart disease, stroke and atherosclerosis. An estimated 4% of men and 2% of women have OSA. One telltale sign is having a shirt-collar size larger than 17 inches. Another sign is loud snoring, although I certainly don't do that. ("Women never snore -- they all deny it," says Dr. White.)
The most effective treatment is a Continuous Positive Airway Pressure machine, which blows air through the nose to keep the airway open. My OSA isn't that bad -- yet. Other remedies include a dental appliance that helps prop the airway open and losing weight, which helps reduce the airway blockage.
Dr. White is also chief medical officer for Philips Home Healthcare, which makes a watch-like monitor, called an Actiwatch, that tracks whether the wearer is moving or still, roughly corresponding with sleep. The Actiwatch doesn't show sleep phases; it generally diagnoses problems with jet lag and body clocks. I wore one for a week, and although I'm still a night owl, it showed nothing amiss in that area.
All in all, "there are plenty of ways you can improve your sleep," Jason Donahue, another Zeo founder, tells me cheerily. This week, I'm starting in on Zeo's tips on keeping disturbances in the bedroom to a minimum. The dog may have to find a new place to sleep.
- Email HealthJournal@wsj.com
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