SleepQuest - Dr. Dement

TOWARD HEALTHY SLEEP:

DR. DEMENT WILL DISCUSS THE FOLLOWING TOPICS IN HIS UPCOMING WEEKLY COLUMNS.

Sleep Need and Sleep Debt.

Each individual has a specific daily sleep requirement. This is the amount of sleep that must be obtained each day on the average to avoid becoming sleep deprived. If the needed amount is not obtained, the lost sleep accumulates progressively as a larger and larger sleep indebtedness.

The True Nature of Sleep.

Sleep is not rest for the brain. If you think we sleep to rest the brain, then it would be appropriate to say the brain never sleeps. The one absolutely defining difference between wakefulness and sleep is this. When awake, we are conscious of the real world and navigate ourselves through it's many challenges primarily in the service of survival. At the moment of sleep, our consciousness of the real world is completely shut down and we are conscious only of the inner world.

What is the Biological Clock?

The biological clock is a term applied to the brain process which causes us to have 24-hour fluctuations in body temperature, hormone secretion, and a host of other bodily activities. Its most important function is to foster the daily alternation of sleep and wakefulness. The biological clock is housed in a pair of tiny bilateral brain areas called the suprachiasmatic nuclei.

Clock-Dependent Alerting (CDA).

The major role of the biological clock in the regulation of sleep and wakefulness is to provide an internal and very powerful wake-up signal to the rest of the brain. We call this signal clock-dependent alerting. CDA fosters consolidated periods of peak alertness, high energy, and optimal mental performance at specific times during the day. When CDA subsides at the end of the day, we are "given permission" to fall asleep.

Sleep is regulated homeostatically.

This means that if you get less sleep than you need, the tendency to fall asleep in the daytime will become progressively stronger; if you get more sleep than you need, the tendency to fall asleep in the daytime will become progressively weaker.

Factors Which "Unmask" the Sleep Debt.

Most people think that a heavy meal, a warm room, a comfortable bed, a boring lecture, an alcoholic beverage will cause sleepiness. None of these things cause sleepiness. Rather, they unmask sleepiness. If you do not have a sizable sleep debt, you will never get sleepy in the daytime.

Drowsiness.

The onset of drowsiness is the moment when staying awake requires a conscious effort, usually an effort to keep the eyes open. This moment is the last step in falling asleep, not the first. In any hazardous or potentially hazardous situation such as driving, the onset of drowsiness should be regarded as a red alert- a powerful signal to get out of harm's way instantly. Strong external and internal stimulation during wakefulness can mask a large sleep debt and a strong underlying tendency to fall asleep. If drowsiness occurs soon after a transition from being active and moving about to a sedentary situation such as driving, your sleep debt is very likely huge and dangerous.

Drowsiness is Red Alert!

If we are paying attention, most of us know when we are about to fall asleep. We know because we feel "drowsy." Most of us associate "drowsiness" with heavy eyelids, difficulty keeping the eyes open, and difficulty concentrating. It is obviously terribly dangerous if we are having difficulty keeping our eyes open while we are driving. If, at this moment, we try to fight off the drowsiness by turning up the radio, opening the window, or slapping our face, we are playing Russian Roulette with three or more bullets in a six chambered revolver.

The feeling of drowsiness is Red Alert! If we don't respond immediately, we will die. Drowsiness means a large sleep debt is winning the battle for our mind and brain. There is only one appropriate response. Get out of harm's way immediately! It is irresponsible and unacceptable to drive drowsy. Driving drowsy is the same thing as driving drunk! Even if we choose to risk our own life and health, we have absolutely no right whatsoever to risk the lives of others.

Can We Build Up a Sleep Debt Indefinitely?

The longest laboratory study of restricted sleep (to 4 hours per day) is 14 consecutive days. In this study, the impairment and fatigue of the subjects was continuing to increase. There was no evidence of a plateau. Until proven otherwise, it must be assumed that we can build up a sleep debt indefinitely.

We Are Not Healthy Unless Our Sleep Is Healthy.

We have learned that we can have a health problem during our sleep which may not be apparent to us when we are awake. Therefore, unless we know our sleep is healthy, we cannot be sure we have total good health.

Sleep disorders: General definitions and classifications.

Sleep disorders are illnesses and disturbances of sleep and wakefulness that are caused by abnormalities existing only during sleep or abnormalities of specific sleep mechanisms. These abnormalities typically produce symptoms during wakefulness that are easily recognized if the person is aware of their significance, but the fundamental pathology exists during sleep.

America is a Sleepy Society.

How many Americans are seriously or dangerously sleep deprived? There is no doubt whatsoever that vast numbers of us in school, in the workplace, in the transportation industry, in a variety of service industries, and particularly, in shift work situations, are carrying a dangerously large sleep debt.

All Wakefulness is Sleep Deprivation.

Regardless of how we feel when we are awake -- tired, elated, energetic, apathetic, interested, bored, all wakefulness is sleep deprivation. Some people think that the ordinary waking day is not sleep deprivation. They are wrong.

Sleep Debt Makes a Sedative a Sedative.

Under laboratory conditions, when the sleep debt of laboratory animals is lowered to zero, or very close to zero, such animals can be given enormous doses of conventional sleep medications with no sleep-inducing effect at all. These doses will strongly sedate, and induce sleep in normal animals. In humans, the amount of prior sleep determines the sedative potency of a low dose of alcohol in the morning.

Can We Get Too Much Sleep?

There is a fairly common experience of feeling lousy or groggy after an unusually long sleep. To conclude that this is due to "too much sleep" is wrong. Sleep is not the culprit. We believe the occasional feeling of grogginess after one night of extended sleep as being the result of a combination of several factors: (1) The extended sleep which leaves people groggy usually follows a period of severe sleep deprivation. Extra sleep on only one night does not substantially reduce the huge debt that has been accumulated. (2) When the sleep deprivation has been associated with a high level of stress, anxiety, and pressure, the long sleep is associated with a general "let down" because the stress is over. (3) The extra sleep usually results in waking up not when clock-dependent alerting is strong, but rather in the midday dip of clock-dependent alerting. (4) If a person has been awake and active for several days, lying in bed for 14, 16, or 20 or more hours usually results in considerable stiffness of the muscles and joints, and may even, through inappropriate positioning, also include a crick in the neck, etc. (5) Finally, when we expect to wake up feeling tremendously restored and energized, and we do not, there has to be a reason. Therefore, we wrongly conclude that we must have "too much sleep."

We Can Be Asleep Without Knowing It.

It is absolutely clear that individuals all fall asleep, wake up, and deny having been asleep. In sleep deprivation situations, there can be microsleeps which subjects deny.

How Many Different Sleep Disorders are there?

Sleep specialists currently diagnose 88 specific disorders, all of which (with two exceptions) were discovered and characterized since 1970 when the world's first sleep disorders clinic opened at Stanford. Some are both very common and very serious. Altogether, at least three quarters of all adults have one or more diagnosable sleep disorder. This makes the continuing failure of the health professions to address this clinical area effectively all the more amazing and sad.

Breathing during Sleep.

Quite possibly the single, biggest problem in the entire health arena is impaired breathing during sleep. Obstructive sleep apnea is the most common chronic illness that human beings suffer. Untreated, it usually progresses to disability, overwhelming fatigue, and cardiovascular disease.

What are the most serious sleep disorders?

My list includes obstructive sleep apnea, restless legs syndrome, chronic insomnia, and the violent parasomnias. Though less common, I also include sudden infant death syndrome (SIDS), narcolepsy, and Fatal Familial Insomnia. SIDS manifests as a single catastrophic event and narcolepsy often reaches its full severity in a relatively short time. Fatal Familial insomnia, a genetically transmitted disease, inevitable causes death about one year after its onset, but is extremely rare.

How Common are Sleep Disorders?

Very much more common than most people realize is the best answer to this question. The national prevalence has been established for only one specific disorder, obstructive sleep apnea, at 24 percent of adult males and 9 percent of adult females. Restless legs syndrome has been estimated to afflict at least 12 million Americans. A recent Gallup Poll has established a national prevalence of 14 percent for chronic insomnia.

Is Snoring a Legitimate Medical Concern?

Very much so. It is likely that every reader will know someone who snores very loudly. This is the cardinal symptom of the obstructive sleep apnea. While not everyone that snores has obstructive sleep apnea, all snorers do have disordered breathing during sleep, an impairment that has the potential of becoming a serious medical concern.

Are Physicians Familiar with Sleep Disorders?

In 1991, the answer to this question was a resounding no. In 2000, the answer is only slightly better. Our conclusion is that primary care physicians, for a variety of reasons, probably the most important of which are cost constraints, lack of awareness, and fear of generating additional expenses, are only occasionally recognizing obstructive sleep apnea, and then, only its most flagrantly, obviously ill victims.

What is America's Largest, Deadliest, and Most Costly Health Problem?

I firmly believe the answer is unhealthy sleep. In my lexicon, unhealthy sleep includes chronic sleep deprivation as well as sleep disorders. Therefore, my answer to the question is pervasive sleep deprivation and undiagnosed and untreated or misdiagnosed and mistreated sleep disorders collectively are American's largest, deadliest and most costly health problem.