Doctors say it may not ruin your life but it can
make your life miserable,
For years now, Allan Rechtschaffen, a psychology
professor emeritus at the University of Chicago, has been watching
what happens when he totally deprives rats of sleep.
He takes a plastic disc with a divider in the middle
and puts one rat on each side. Both rats get plenty of food, and one
rat -- the lucky one -- also gets to sleep whenever it wants.
But every time the other rat dozes off, the disc
starts to spin slowly, forcing both rats to jump up and walk forward
to keep from falling into a shallow pool of water.
The result? After two or three weeks of total
sleep deprivation -- probably the equivalent of 8 to 12 weeks for
humans -- the sleepless rats all die.
During their downward spiral, their body
temperature goes up, they develop skin lesions and food intake
doubles. They show no changes in immune function.
``We don't know what the rats die of,'' says
Rechtschaffen, but ``sleep seems to be almost as important for an
organism as food.''
Intuitively, that seems obvious. And researchers
have documented some very real consequences of sleep loss, which
affects not only America's 30 to 60 million chronic insomniacs but
millions of others who are just too busy to sleep or have a medical
problem like sleep apnea or restless leg syndrome.
Sleep apnea, which affects at least 2 percent of
women and 4 percent of men and can trigger potentially serious
cardiovascular problems, causes a person to wake up repeatedly to
breathe. Restless leg syndrome and involuntary jerking of the legs
during sleep can also make it hard to fall and stay asleep.
Yet the surprising thing about all this research
is that while more than 1,000 studies show that a bad night's sleep
-- or a string of them -- can lead to decreased intellectual
function, mood and performance, there's little evidence so far that
sleep loss has direct health consequences.
Except, of course, if you count the 1,500 deaths
and 76,000 injuries a year from driver fatigue, accidents that
happen when the brain is vulnerable to ``intrusions of microsleep
episodes,'' says Dr. Charles Czeisler, chief of circadian and sleep
disorders medicine at Brigham and Women's Hospital.
Still, overall there is ``no solid evidence that
sleep loss leads to long-term medical problems,'' says Gregg Jacobs,
an insomnia specialist at Beth Israel Deaconess Medical Center.
It does cause ``psychological suffering,'' says
psychiatrist William C. Dement, director of the Stanford Sleep
Research Center and Sleep Disorders Clinic. ``But we can't say, yes,
if you don't treat your insomnia you are going to die.''
To be sure, insomniacs are ``more likely to report
poor health,'' notes Cynthia Dorsey, director of McLean Hospital's
sleep disorders center, but it's not clear which comes first.
Twenty years ago, researchers found that people
who slept more than nine hours or less than six a night had a higher
death rate than those whose sleep was closer to the seven or eight
hours that most people need. But this was a correlation, not
documented cause and effect.
Recently, there has been new evidence -- about a
dozen studies -- suggesting that immune function may change with
sleep loss, but whether this translates into a health risk is also
unknown.
Several years ago, Dr. Michael Irwin , a professor
of psychiatry at the University of California at San Diego,
published a study of 23 middle-aged male volunteers who were
awakened at 3 a.m., making them miss about four hours' sleep.
Irwin found that this modest sleep loss was
correlated with a a drop in the activity of natural killer cells, a
type of immune cell. But this bounced back fully after a good
night's sleep.
In another study this year, Irwin deprived 42
middle-aged men of sleep in the early part of the night and found
decreases in several immune measures, including a substance called
Il-2. It was not clear when these measures began to bounce back.
But other studies -- and there are still too few
for a definitive conclusions -- suggest a different picture.
In fact, some measurements of immune function
actually go up with sleep loss, says David Dinges , director of the
experimental psychiatry unit at the University of Pennsylvania
School of Medicine, a researcher who says he has ``sleep-deprived
more people than anyone else.''
In a 1994 study of 20 adults deprived of sleep for
64 hours, Dinges found an increase in white blood cells and natural
killer cell activity, a measure of immune response.
At least in the sleep lab, he says, where
researchers go to great pains to keep people in a good mood, sleep
deprivation seems to be linked to ``an increase in immunological
defense,'' though the overall picture of immune effects is far from
clear.
What is clear, researchers agree, is that
sleepless people are not happy campers -- or as good thinkers as
usual.
``Sleep deprivation has a clear impact on physical
performance, cognitive performance and mood,'' says Dr. David White,
director of the sleep disorders program at Brigham and Women's and
past president of the American Sleep Disorders Association, a
professional organization.
But lousy mood can be the cause as well as the
effect of lousy sleep. ``Nobody knows if depression causes insomnia
or vice versa -- it's very circular,'' says Dinges.
Anxiety, too, can be part of a vicious circle
because ``secondary anxiety'' can leave people ``freaked'' about
their loss of sleep, says Dr. John Winkelman, associate director of
the sleep disorders service at the Brigham.
Making mood worse after a bad night, or several,
is the all-too-keen awareness that you may be having more trouble
than usual remembering things or processing information, although
motivation -- such as trying to keep your job -- may offset this.
Still, there's no question that if you have a
bunch of bad nights in a row, you build up a significant ``sleep
debt,'' which means working memory may fail, reaction time slows and
it becomes harder to pay attention.
Yet this is the devil with which growing numbers
of us live -- whether we're insomniacs or just don't take the time
to rest. As a nation, we're getting 20 percent less sleep than our
forebears did a century ago, according to the National Commission on
Sleep Disorders Research.
And we're clearly paying the price. A Gallup
survey this year showed that a third of us have significant daytime
sleepiness, which can be dangerous as well as unpleasant. A Harris
survey, also done this year, found that 70 percent of people
acknowledge that their concentration is poor or fair when they're
sleep deprived.
So what should you do if you're stuck in
sleep-loss hell?
For openers, if you're sleeping only four or five
hours a night because you're too busy or working too hard or
socializing too late, put yourself to bed and get more sleep.
If you've got a stubborn case of insomnia, tell
your doctor. You may have an underlying problem with anxiety or
depression; treating these problems can lead to greatly improved
sleep.
That goes for sleep apnea, too. Many people deny
they have trouble breathing during sleep for the obvious reason that
they're too groggy to remember. But apnea is both serious and
treatable, so if your spouse says your snoring is terrible, take it
seriously.
Restless leg problems, too, are treatable, usually
with medications.
And if you've got chronic insomnia?
Despite their bad reputation, sleeping pills may
be an answer for some people. A relatively new short-acting one
called Ambien appears to cause less dependence than the older,
longer-acting benzodiazepines in vogue 10 years ago.
Many people also swear by nonprescription potions
like melatonin, which is sold as a dietary supplement, although the
scientific jury on that is still out.
But the best long-term solution for many people is
to change behavior and attitude, which means sticking to a regular
sleep-wake schedule and trying not to worry about sleep loss.
``The main problem with insomnia is people worry
about their sleep,'' says Peter Hauri, author of the bestseller,
``No More Sleepless Nights.'' If you worry that sleep loss will
wreck your health, ``you'll try even harder to sleep and sleep even
less.''
So there's another tidbit to remember as you toss
and turn.
``The most astonishing thing,'' says Dinges, is
that one or two good nights' sleep ``has a marked effect in
reversing nearly all of the physiological and brain and immune
function changes induced by sleep deprivation.''
SIDEBAR:
For a better night's sleep.
If you're struggling with sleep, tell your doctor. If
he or she can't help, you can probably find a sleep specialist to
diagnose and treat your problem at almost any major hospital.
You can also practice habits designed to help your
sleep:
- Don't try too hard to sleep. It can make
things worse.
- Don't drink alcohol or water, or smoke
cigarettes near bedtime; don't drink caffeinated beverages after
midafternoon.
- Exercise may help, although the data on this
are mixed. But don't exercise within three hours of bedtime.
- Schedule ``worry time'' in the early evening,
then wind down.
- Restrict time in bed to seven or eight hours.
Spending too much time in bed not sleeping can make it harder to
sleep.
- Get up at the same time every day, even on
weekends.
- Don't let bed become a negative emotional
cue. Stay in bed only when you're relaxed. If you can't sleep,
get up and do something relaxing until you feel drowsy.
Judy Foreman’s column runs every other week. Past
columns are available on
www.myhealthsense.com.
Listen to her live
call-in webcast radio show every Wednesday night
from 8:30 to 9:30 EST on
http://www.healthtalk.com.