Sleep Disorders
Klein-Levin syndrome causes people to sleep for days; during this time they may walk to the bathroom or refrigerator without ever remembering leaving bed. Those who suffer sleep-wake cycle disorders may fall asleep later each night because their bodies run on a 26- or 27-hour cycle. Others regularly wake up with excruciating headaches or muscle spasms that jerk their legs out of bed. Hypnophobics fear going to sleep; still others feel hypnalgia, or dream pain.
1. Narcolepsy, or “Sleep Attacks.” Sleepy all the time, people with narcolepsy sometimes fall asleep without realizing it. The disorder afflicts 1 in 2000. Typically, its victims do not realize their sleepiness as a sign of disease and thus do not consult a physician. They may be diagnosed a full 10 to 15 years after their symptoms first appear. William Dement reports the case of a woman with narcolepsy who once fell asleep 20 feet under water while scuba diving, and another of a fireman who had an attack while climbing a ladder to a burning building. Falling asleep in the middle of lovemaking is not unusual for people with narcolepsy. The most dramatic component of the syndrome is cataplexy—attacks of muscle weakness or near-total paralysis. The sleep attack is often triggered by the intense emotion associated with stress, laughter, anger, or surprise. CBS’s 60 Minutes once broadcast an episode in which a man made a superb pool shot and suffered an attack. Later in an argument with his son he suffered another attack. Sleep attacks generally last less than 5 minutes but may last up to 20 minutes.
Research indicates that people with narcolepsy enter REM sleep within a few minutes of dozing off, a pattern called sleep onset rapid eye movement (SOREM).The extended periods that victims spend in REM sleep may deprive them of deep sleep, the phase that is important to physical recovery and feeling alert in the morning. In short, the daytime drowsiness of people with narcolepsy may result from a failure in the mechanism that governs REM sleep. More recent research suggests that the biochemical cause of this abnormal sleep pattern may be the neuropeptide hypocretin, a tiny brain molecule produced at the back of the hypothalamus. When first discovered, it was thought to be an appetite regulator. New evidence has connected the lack of hypocretin to narcolepsy.
At present, there is no cure for narcolepsy. Many of those suffering from the disorder take amphetamines to combat the daytime sleepiness. Some require antidepressants to treat cataplexy and dreamlike hallucinations. Physicians may also prescribe behavioral interventions such as scheduling naps during the patient’s sleepiest times. Some researchers suggest that the best approach will likely be the replacement of missing hypocretin.
2. Sleep Apnea. Apnea literally means “cessation of respiration.” It is a serious disorder, potentially life threatening. In apnea, the change from wakefulness to sleep causes the central nervous system to cease functioning. There are two forms of apnea: In central sleep apnea, after the individual falls asleep, the diaphragm stops moving because the brain no longer sends impulses to control it; in upper-airway sleep apnea, breathing is blocked by loss of muscle tone in the tongue, throat, and larynx. Intermittent loud snoring frequently accompanies the disorder as the individual struggles to fill the lungs with air. In addition, elevated blood pressure may occur, placing additional strain on the heart. After about 60 to 100 seconds of sleep, the person awakens and takes a series of choking breaths. As a rule, the arousal lasts a few seconds as the blood gases quickly normalize and the person returns to sleep. The cycle repeats itself throughout the night. Some patients may awaken as many as 500 times but may be so habituated to their disorder they are unaware of having awakened at all. They are oblivious to the fact that they cannot breathe and sleep at the same time. Others, however, do not return to sleep immediately after the apnea and complain of insomnia. Nasal CPAP (continuous positive airway pressure) has proven successful with some victims.
A fan provides a stream of air through a small plastic mask worn over the nose during sleep. Patients must sleep with the mouth closed, aided by a chinstrap. The forced air opens the constriction and allows a normal flow of oxygen into the lungs.
3. Sleepwalking and Night Terrors. These disorders occur primarily in children and typically disappear by adolescence. However, they can continue into adulthood. Parents who worry about the psychological significance of the episodes probably suffer more than their children, who typically wake up the next morning unaware that anything unusual has happened. Laboratory studies indicate that these episodes occur in the first deep stage 4 sleep of the night and are generally associated with body movements and intense autonomic activation. Brain-wave recordings indicate that both sleepwalkers and night terror victims are passing back and forth rapidly between sleep and wakefulness.
Sleepwalking often occurs when people are very sleep deprived. The night terror is typically accompanied by a blood-curdling scream that brings parents rushing to the child’s bed. The dazed and groggy child cannot report what is wrong. Typically, the child falls back to sleep more quickly than the parents and is normal the next day. These non-REM sleep disorders tend to run in families. One of Dement’s patients claimed that everyone in his family was a sleepwalker. He recounted the story of a family reunion at Christmas in which he found himself surrounded by all his sleeping relatives in his grandfather’s dining room.
4. Insomnia. In the U.S. National Sleep Foundation “2008 Sleep in America” poll, 65 percent of respondents reported that, within the past year, they had experienced a “sleep problem” at least a few nights a week, and 44 percent said they had experienced at least one symptom every night or almost every night. The more common symptoms of insomnia include waking up feeling unrefreshed (49 percent) and being awake a lot during the night (42 percent). Less frequently reported symptoms are difficulty falling asleep (26 percent) and waking up too early and not being able to get back to sleep (29 percent). Thomas Roth, chief of the division of sleep medicine at Henry Ford hospital in Detroit, Michigan, attributes the increasing problem with insomnia to the aging of the U.S. population and to the growing demands placed on people. As the large baby boom generation gets older, sleeping problems will likely rise. As for stress and work, 25 percent of adults believe they cannot be successful and get enough sleep. About 70 percent of those with insomnia never tell their doctors. When insomnia occurs most nights for three to four weeks, it is considered chronic. Chronic anxiety, depression, situational stress, and stimulus overload are among the important psychological causes of insomnia that account for about 50 percent of all cases. Drugs, including caffeine, alcohol, and nicotine, account for another 10 percent of all cases. Decongestants as well as drugs prescribed for asthma and emphysema may keep one awake. Medical problems lie behind another 10 percent of all cases. For example, patients with congestive heart failure or emphysema may have breathing problems that keep them awake. Restless leg syndrome and related neuromuscular disorders may produce restlessness and muscle spasms that interfere with sleep. About 30 percent of insomnia cases occur for no apparent reason. Referred to as primary insomnia, it is treated with behavioral techniques and, when necessary, medication.
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