Volume 9, Issue 4: Medicus
Sleep-Blessing or Curse
Sleep makes an auspicious debut on the human scene. Our Lord used sleep as an anesthetic in order to remove Adam's rib to make woman (Gen. 2:21). From the approximately two dozen references to sleep in the rest of the Bible, representing a half-dozen or so different categories, we can conclude that sleep is very important and the subject of sleep very complex. As I read through the texts, they seemed to fall into categories of sleep as death, separation, reward, laziness, and limited references to brevity and dreams. A summary might be if God gives sleep it is sweet, but if man takes sleep it is laziness, separation, and death. At the very least sleep can provide a window into spiritual life. If you or someone you love is having problems with sleep, the first area to examine is spiritual. However, if this pursuit in non-productive, the cause may be biological, and there may be a solution.
The following recent findings can start to help us understand this part of our lives under the sun. In the early part of this century, scientists began to examine sleep from a physiological perspective. In 1953 the landmark discovery of rapid eye movements (REM) during sleep was made. In 1958 it was noted that sleep in animals also had a cyclic organization, creating an explosion of fundamental research that pulled together researchers from many different fields - electro-physiology, biochemistry, pharmacology - and led to the identification of REM sleep as an independent state of alertness. This type of research, as well as discoveries of the presence of apnea during sleep in a subgroup of "Pickwickian" patients (1965), led to a flurry of investigations of the control exercised by the "sleeping brain" on the body's vital functions. This type of work eventually led to the new discipline of "sleep medicine."
About forty million Americans suffer from sleep disorders such as narcolepsy, sleep apnea, restless leg syndrome and the insomnias. Many of them are unaware. Each year sleep disorders, sleep deprivation, and sleepiness add about 15.9 billion to America's health bill and result in reduced productivity, lowered cognitive performance, increased likelihood of accidents, higher morbidity and mortality risk, and decreased quality of life. In a recent large population-based survey, researchers found that 24 percent of men and 9 percent of women had sleep-disordered breathing. The prevalence of the sleep apnea syndrome, characterized by sleep-disordered breath and daytime hypersomnolence, was 4 percent in men and 2 percent in women.
In addition, obesity was strongly associated with sleep-disordered breathing. Age was not. A history of habitual snoring was associated with severe sleep apnea. It has been found that 40 percent of obese men and 3 percent of obese women had sleep apnea that required intervention. A recent study looking at sleep apnea in women showed that most of the women were not obese, many had menstrual abnormalities which improved with treatment of their sleep disorder, and many had certain cranio-facial features.
The word, "apnea," comes from the Greek meaning "want of breath." The standard definition of a sleep apnea episode is a cessation of air flow at the nose and mouth lasting ten seconds or longer, always occurring in sleep, and terminated by waking. Apnea episodes can be documented by polysomnography, a standard method of measuring the activity of the brain, the eyes and the muscles from a sleeping subject. Obstructive sleep apnea is the most common serious sleep disorder and is defined by cessation of air flow despite persistent and increasing attempts to breathe. Central sleep apnea is characterized by cessation of air flow resulting from termination of respiratory effort. Mixed sleep apnea is simply a combination of the two, in which a brief central apnea gives way to an obstructive phase.
Sleep apnea is almost always associated with a decrease of oxygen and an increase of carbon dioxide in the blood. In a single night, a patient with sleep apnea may have hundreds of apneas. Patients who snore loudly and are unambiguously sleepy in the daytime are almost always afflicted with this type of apnea.
Studies done linking sleep apnea with heart attacks have concluded that the presence of more than five apnea episodes per hour is an independent association with a heart attack. Sleep apnea syndrome may be associated with higher rates of heart attack, stroke, hypertension, and cardiovascular mortality, and can lead to impairments in daily function due to hypersomnolence like falling asleep while driving.
There is treatment for obstructive sleep apnea in the form of continuous positive airway pressure (CPAP). Nasal CPAP acts predominantly by providing a physical "pressure" splint to the upper airway. This prevents the inspiratory suction from collapsing the airway. Although the apparatus seems imposing at first, most patients tolerate it in trade for a good night's sleep.
Insomnia is more common. The most recent survey, carried out in May 1991, found that 36 percent of the entire adult population of the U.S. had a problem with insomnia. Of these, 75 percent reported intermittent episodes and 25 percent had chronic insomnia. Transient insomnia extends from one or two nights to one or two weeks, with persistent insomnia more likely to be associated with a psychological or medical problem.
Other sleep disorders include circadian rhythm sleep disorders, narcolepsy, REM behavior disorder, restless leg syndrome and periodic leg movements. All of these represent specific medical problems and have good treatment methods available once the diagnosis is established.