by Sheri B. Doniger, DDS
Here are some myths about sleep as adapted from from a quiz posted by the Sleep Foundation (www.sleep foundation.org). Do you think any of them are more fact than fiction?
• During sleep, your brain rests.
• You can function on with fewer than normal hours of sleep.
• Boredom makes you feel sleepy, even if you have had enough sleep.
• Resting in bed with your eyes closed can satisfy your body's need for sleep.
• Snoring is not harmful as long as it doesn't disturb others or wake you up.
• The older you get, the fewer hours of sleep you need.
• Most people do not know when they are sleepy.
• Raising the volume of your radio will help you stay awake while driving.
• Sleep disorders are mainly due to worry or psychological problems.
• The human body adjusts to shift work.
• Most sleep disorders go away without treatment.
If you agreed with any of the statements about myths associated with sleeping, you were incorrect. Please read on.
Sleep! Remember when we were younger, and we could sleep until noon or beyond? Now, with more responsibilities of work and family, we have shortened our recommended eight to nine hours of rest down to less than five. There are many reasons why sleep is elusive.
Our nation is in a sleep "debt," according to the American Academy of Sleep Medicine. We have increased our work time, our drive time, our family time, and our play time, resulting in a decrease of sleep time. Yes, there are still only 24 hours in a day. There are only so many waking hours. But, Americans today are burning the candle at both ends and trying to make the most of their 24 hours. This is creating several health issues.
Lack of sleep has been shown to be the cause of a decrease in work productivity, difficulty concentrating, increase in work errors, and car accidents. According to the National Highway Traffic Safety Administra-tion, accidents are frequently caused due to a driver who falls asleep at the wheel. An estimated 100,000 police-reported crashes occur due to sleepy drivers where fatigue was identified as a cause (and more than 1,500 of those crashes involve a fatality). One million auto accidents are attributed to driver inattention or lapses, which are more likely to occur due to sleep deprivation or fatigue. This is a national crisis. Billions of dollars are spent each year on sleep related issues.
How much sleep is enough? The recommended eight hours of sleep may be perfect for many. Some can get along with a little less; some need a little more. A suggested way to find out how much sleep is necessary is to sleep until you feel rested. On vacation, go to sleep at a normal time, and wake up unrestricted. We can judge how we feel in the morning after a good night's sleep. We have all had the urge to roll back over and take a few extra minutes. The need to sleep does not decrease with age, as we may have thought. We need the same amount of sleep; it is just that we may not be able to achieve the necessary hours. Due to illnesses, medications, or other factors, the duration and quality of sleep may be altered.
Our body clock works on circadian rhythm, or the "regular changes in mental and physical characteristics that occur in the course of a day (circadian is Latin for "around the clock"). This body clock is governed by the suprachiasmatic nucleus (SCN), which is a group of neurons (approximately 20,000) that are situated in the hypothalamus. The signals from the SCN travel to the pineal gland, which affects the production of melatonin. With darkness, melatonin levels increase, causing sleepiness. Circadian rhythms can also be affected by external time cues, such as alarm clocks or meal times.
When we sleep, our body repairs. The term "beauty rest" is not far from the truth. Our body makes reparative proteins while we sleep. Growth hormones are secreted during the night in children and young adults. Sleep appears necessary for survival, as we are more alert and able to concentrate more efficiently after a good night's rest. Recent evidence may point to the increase in the severity of age-related chronic disorders, such as diabetes and high blood pressure in those with sleep disorders.
The sleep cycle is composed of five stages. The entire process occurs over the course of two hours, and can occur several times during the night. There are alternating patterns of REM and non-REM sleep. REM (rapid eye movement) or dream sleep usually occurs two hours each night. Contrary to popular belief, there is a great deal of mental and physical activity during REM sleep — breathing and heart rates are increased, and our muscles become temporarily paralyzed. Non-REM sleep, or stages 1, 2, 3 and 4, occur in a cycle, preceding the REM state. Fifty percent of our total sleep time is spent in the second stage, 20 percent in REM sleep, and 30 percent in the remaining stages. Deeper sleep consists of stages 3 and 4. (See Table 1)
Reasons for sleep loss are many, with stress being the number one reason. Jet lag, alcohol, caffeine, diet, external noises, pain, medications, anxiety, and depression are all causes for loss of sleep. Schedule changes or irregular sleep times may also affect the amount of sleep. Poor sleep habits are also engrained. We may just "like" to stay up late, no matter if our bodies tell us we need to get to sleep. Additional reasons that keep us awake at night include:
Exercise or intense activities late in the day
Environmental conditions in the bedroom, such as too hot, too cold or too bright
Physical conditions such as illness
Unique females issues, such as pregnancy and menopause
Insomnia affects nearly 60 million Americans. Normally, it should only take about 10 to 20 minutes to fall asleep at night. Insomnia sufferers have difficulty falling asleep, or staying asleep all night. Females are most affected. Additionally, insomnia is a symptom of a sleep disorder and may be a sign of an underlying medical disorder. Insomnia can be transient, short or long term. Transient insomnia can occur due to stress, emotional excitement, or change in sleeping environment. Short-term insomnia, which spans a few weeks, is usually caused by stress, emotional or medical conditions. Long-term insomnia is the most serious, as it may be related to depression, or to other psychological or medical issues. The first two are treated by removing the source of the problem; the latter may require further medical intervention.
More than 70 sleep disorders exist. Some of these problems are short term, others are long term, and many are treatable. Several sleep disorders, some recommended therapies, and what you can do to solve your own sleep debt are discussed below.
Excessive daytime sleepiness will occur due to many sleep disorders. The feeling of drowsiness occurs, and there is an overwhelming desire to fall asleep, sometimes at inappropriate times, even after adequate night-time sleep. Lack of concentration, decreased performance and frustration due to misinterpretation of "tired-ness" is evident. (See Table 2)
Sleep apnea is more than just snoring loudly. It is literally "lack of breath." Over 18 million adults snore. Normal snoring is harmless. When snoring becomes oxygen stealing, it becomes a problem.
Three types of sleep apnea exist. Obstructive apnea is the most common. It occurs when the muscles of the pharyngeal area become flaccid, blocking the ability of oxygen to flow from the oral/nasal cavity to the lungs. The apnea period can occur for 10 seconds or more, causing the sufferer to be awakened, often unnoticed, due to oxygen deprivation. These awakenings, along with loud snoring, can occur several times during the night. Central apnea occurs when the airway is patent but the diaphragm and chest muscles fail to function. Snoring may not be a symptom of this type of apnea, but the awakenings are common, as gasping for breath occurs. Mixed apnea is a combination of both, with a long period of obstructive apnea followed by a period of central apnea.
Sleep apnea occurs more in middle to older aged men; most are overweight. It affects approximately six million Americans. They exhibit excessive daytime sleepiness due to the frequent awakenings during the night. Dentistry can aid in mild to moderate cases of sleep apnea, with jaw and tongue positioning devices. Chronic obstructive apnea is treated with a device called CPAP (continuous positive airway pressure). This device is fitted over the patient's nose and mouth, and supplies continuous airflow during the night. Weight loss or change of sleeping position may also be suggested for some of these patients. Additionally, surgical alteration of the tonsilar or uvular area has been recommended.
Narcolepsy is a neurological disorder that results in sudden "sleep attacks," affecting 250,000 Americans. The person goes from wakefulness into REM sleep, sometimes with no apparent predictors, even after an adequate night's sleep. Cataplexy is common with narcolepsy, especially after emotional situations. The body loses its muscular control, rendering a person so weak they sometimes fall to the ground. Additionally, vivid dreams are recalled and some experience hallucination-like symptoms. Although falling asleep occurs in less than five minutes, night-time sleep is usually disrupted and excessive daytime sleepiness is experienced. Narcolepsy appears to be a hereditary disorder of sleep regulation, affecting adolescents through adults. The treatment is usually pharmacologic.
Restless leg syndrome (RLS) and periodic leg movement syndrome (PLMS) are both disorders that occur in older adults, usually in patients over the age of 65. RLS is a hereditary condition that affects more than 12 million Americans. It causes a sensation of crawling, prickling, or tingling in the legs and feet, even when the body is at rest. There is an urge to move them for relief. Constant leg movement occurs during the day and night, leading to insomnia, fatigue and excessive daytime sleepiness. PLMS exhibits a repetitive jerking of the legs, feet and toes, especially while asleep, leading to recurrent awakenings as well. These symptoms may go unnoticed, except that insomnia and excessive daytime sleepiness occur.
Many people with RLS also have PLMS. There is no cure for either of these disorders, but they are usually managed with medications.
Circadian rhythm disorder occurs when we work in different shifts. Our body clocks are based on the "awake during daylight, asleep during dark" premise. When we alter that by working a non-traditional schedule, our body pays for it. We try to stay up during the day to utilize our light hours, when we should be sleeping to refresh our minds and our bodies. Jet lag may also be considered a circadian rhythm disorder. Transcontinental and transoceanic travel affects our personal clocks. When we go from west to east, we "lose" several hours of our day. It takes a few days to adapt. Additionally, long-distance drivers or those driving through the night can be susceptible to alterations in the circadian rhythm.
Issues that affect older individuals can also impact on sleep. We do not lose the need for eight hours of sleep; we just lose the ability to sleep for longer periods of time. The primary reason for loss of sleep in older individuals is pain. Night-time pain can be from the back, headache, sinus, or a myriad of other manifestations. Medical conditions, such as arthritis, osteoporosis, heartburn, Parkinson's disease, Alzheimer's disease, gastrointestinal reflux and incontinence, can affect the individual's efforts to sleep through the night. Medications used to treat some of these disorders also may keep people awake, such as antidepressants or antihypertensives. In addition, multiple medications from multiple doctors treating the same patient may have potentiating effects. Menopause and hot flashes are additional reasons for awakenings. Bereavement and other stressful or psychological events can cause a change in sleep pattern. Before treatment can be instituted, the cause should be addressed, as different therapies exist for different etiologies.
Parasomnias are other issues that will interrupt our night's sleep and the sleep of others in our environment. Sleep walking, sleep talking, and sleep tremors are all usually childhood issues. They appear hereditary in nature and children grow out of them as they reach adulthood. Occurring more often in males than females, REM disorder occurs when one "acts out" dreams. Normally, in REM sleep, the body is in a state of paralysis. In this disorder, the paralysis does not occur and sometimes violent behavior may result. Vivid dreams are recalled. Parasomnia is treated with medication.
Therapies utilized to assist patients who have sleeplessness are varied. As we discussed, sleep apnea treatment may involve either something as benign as weight loss or as major as surgery. Behavioral changes are also indicated. Weight loss, change in sleep/wake schedule, regular exercise, eliminating caffeine, smoking cessation, or psychotherapy may be suggested. Pharmacological means are also prescribed, in cases of severe depression or possibly alcohol abuse. Light therapies are sometimes utilized. The American Academy of Sleep Medicine offers some practices that are conducive to a good night's sleep. (See Table 3)
Remember, naps aren't all that bad! Personally, I can't function without my nap on the afternoons I am off. Naps can be restorative. A short 15 to 20 minute nap can increase alertness, reduce fatigue and sharpen memory. However, naps should not be used to make up for a bad night's sleep or if you are having problems getting to sleep at night.
True sleep disorders are diagnosed by a physician in a sleep clinic. If you suspect a patient, a partner, or yourself of having a sleep disorder, help is a phone call away. The Academy of Sleep Medicine recommends seeking medical help if you have symptoms of sleep deprivation for longer than a month.
Driving remains a key concern. As mentioned, one-sixth of all accidents are due to driver inattention or lapses in focus. Frequent stops should be made during a trip. Driving with a companion, and avoiding performance-impairment medications also help prevent accidents. Drivers should be concerned with signs of fatigue, such as not remembering the last miles driven, missing familiar landmarks, or difficulty keeping their head up.
It is important to sleep the proper amount of time you need to feel rested and alert the next day. We have trained our bodies to adapt to less than the normal amount of sleep. To quote Benjamin Franklin, "Early to bed, early to rise makes a man healthy, wealthy, and wise." Going to sleep relaxed, setting a schedule for a proper bedtime, and sleeping until sunlight can assist our physical and emotional well-being. Did you have your proper ZZZs last night?
Sheri B. Doniger, DDS, practices in Lincolnwood, Ill. She graduated from the University of Illinois College of Dentistry in 1983 and obtained her bachelor's degree in dental hygiene from Loyola University of Chicago in 1976. She can be reached at (847) 677-1101 or [email protected].
Table 1Sleep Stages
Stage 1 Light sleep. We drift in and out and can be awakened easily. Our eyes move slowly and muscle activity slows.
Stage 2 Our eye movements stop and our brain waves become slower with occasional bursts of rapid waves called sleep spindles.
Stage 3 Deep sleep. Extremely slow brain waves called delta waves appear, interspersed with smaller, faster waves.
Stage 4 Deep sleep. The brain produces mostly delta waves. There are no eye movements and no muscle activity.
Stage 5 REM sleep. Breathing becomes more rapid, irregular, and shallow. Eyes jerk rapidly, limb muscles become temporarily paralyzed. Dreams almost always happen in this stage, but may occur in other sleep stages as well.
It takes about two hours to go through all five stages of sleep, and then they repeat. Rapid eye movement (REM) sleep usually occurs about 90 minutes after we fall asleep. Adults spend half of their sleep time in stage 2, 20 percent of the time in REM sleep, and 30 percent in the other stages. Infants start out spending about half of their sleep time in REM sleep. Older people spend relatively little time in stages 3 and 4.
(Source: National Institutes of Health, http://www.fda.gov/fdac/features/2002/602_sleep.html)
Table 2Causes of Excessive Daytime Sleepiness
• Sleep apnea
• Narcolepsy
• Periodic leg movements (PLMS)
• Restless leg syndrome (RLS)
• Circadian rhythm disorder
A good night's sleep
• Try to sleep only when you are drowsy.
• If you are unable to fall asleep or stay asleep, leave your bedroom and engage in a quiet activity elsewhere. Do not permit yourself to fall asleep outside the bedroom. Return to bed when — and only when — you are sleepy. Repeat this process as often as necessary throughout the night.
• Maintain a regular rising time, even on days off work and on weekends.
• Use your bedroom only for sleep and sex.
• Avoid napping during the daytime. If daytime sleepiness becomes overwhelming, limit nap time to a single nap of less than one hour, no later than 3 p.m.
• Distract your mind. Lying in bed unable to sleep and frustrated needs to be avoided. Try reading or watching a videotape or listening to books on tape. It may be necessary to go into another room to do these.
• Avoid caffeine within four to six hours of bedtime.
• Avoid the use of nicotine close to bedtime or during the night.
• Do not drink alcoholic beverages within four to six hours of bedtime.
• While a light snack before bedtime can help promote sound sleep, avoid large meals.
• Avoid strenuous exercise within six hours of bedtime.
• Minimize light, noise, and extremes in temperature in the bedroom.
Source: American Academy of Sleep Medicine, www.aasmnet.org