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2002 First Paper
For centuries, man has relied on alcohol as a relaxant, often employing its sedative qualities to induce sleep. However, while a stiff drink before bed may initially help one fall asleep, recent research shows that alcohol adversely affects sleep patterns. Not only do recreationally drinkers experience disruptions in their nightly sleep, but alcoholics also damage their ability to obtain quality sleep, perhaps irreparably. Also, sleep problems such as insomnia may cause a person to abuse alcohol, leading into a vicious cycle which corrupts their ability to sleep peacefully. In addition, sleep problems may pave the way for an alcoholic's relapse, as they seek out a familiar form of relaxation. The harmful effects of alcohol outweigh the initial sleep inducing benefits, as an overindulgence in alcohol may result in permanent difficulties with sleep.
Sleep takes place in two distinct stages. The first, called slow wave state (SWS), is a deep, restful sleep characterized by slowed brain waves. The second is known as rapid eye movement (REM) sleep, a less restful state associated with dreaming. Alcohol affects sleep patterns by interfering with the monoamine neurotransmitters which control the body's ability to sleep peacefully (1). In those individuals who drink alcohol but do not abuse the substance, a drink or two before bed helps lessen the amount of time needed to fall asleep. However, contrary to popular opinion, alcohol will not promote a good night's sleep. Even a trace presence of alcohol in the bloodstream disrupts the second half of a person's sleep cycle, leading to wakefulness in the middle of the night and an inability to fall back to sleep. Such disturbances lead to daytime fatigue, which can affect a person's ability to undertake such everyday tasks as driving a car. Alcohol consumed up to six hours before bedtime can still disturb one's sleep cycle that evening. Unfortunately, the majority of alcohol consumption takes place from dinner on, leaving many susceptible to a fitful night (4).
Alcohol also has the tendency to exaggerate existing sleep problems, such as insomnia and sleep apnea. An insomniac, a person who has difficulty sleeping, may seek the aid of alcohol in order to fall asleep, but a reliance on alcohol leads to wakefulness later in the night and a compounded inability to fall back to sleep. Sleep apnea, a breathing disorder in which the pharynx, or the upper air passage, constricts during sleep, affects the body's ability to get enough oxygen. Usually, the shock of not being able to breathe wakes the person, but if she or he has been drinking, the body may not react to the situation as quickly as is necessary. As a result, those with sleep apnea run a significant risk when they consume too much alcohol. Even by ingesting as few as two alcoholic drinks a night, those suffering from sleep apnea place themselves at a much higher likelihood for heart attack, stroke, or death by suffocation (2).
The effects of alcohol on sleep increase among those who abuse the substance on a regular basis, otherwise known as alcoholics. Insomnia affects 18% of the alcoholic population, a higher percentage than found in the population at large (1) . As a person consumes an excess amount of alcohol, the sedative properties of the substance lower significantly, and the alcohol no longer enables one to fall asleep quicker. In fact, consuming too much alcohol makes it increasingly difficult to fall asleep. Once sleep finally sets in for an alcoholic, the time spent in both SWS and REM modes is reduced, resulting in an overall reduction of sleep time. While studying recovering alcoholics during their periods of withdrawal, researchers observed an increase in the amount of time spent in SWS and REM sleep with a corresponding increase in the amount of time needed to fall asleep (5). However, although SWS and REM times were increased, they were not restored to their optimal levels. Research indicates that the damage an alcoholic does to his or her system while abusing the substance may be irreparable (1). In any case, sleep patterns are significantly affected for at least two years, if not for life.
The reverse side of alcohol and sleep problems is the effect an inability to sleep may have on one's reliance on alcohol. Insomniacs may at first employ a drink before bed as a sleep aid, noticing its relaxing properties. However, as alcohol in fact worsens a person's ability to sleep, this initial benefit will wear off as time progresses, leading the insomniac to drink more and more in order to produce the desired effect. Unfortunately, as discussed earlier, an over-consumption of alcohol actually reduces its sedative qualities and increases the difficulty of being able to fall asleep, a dangerous side effect for a person who already has problems falling asleep. If the insomniac becomes too reliant on alcohol for sleep purposes, he or she may develop a dependence on alcohol which could progress into alcoholism, permanently disrupting their sleep patterns and causing an interference in their ability to perform simple tasks. Also, an inability to sleep may cause a recovering alcoholic to seek the familiar comforts of alcohol, triggering a relapse (4).
Alcohol related sleep problems affect more than just adults. Drinking while pregnant or nursing has been shown, besides other damaging effects, to alter the sleep patterns of a newborn baby. The baby absorbs the alcohol into its bloodstream just as an adult would, leading to wakefulness throughout the night, frightening dreams, and a decrease in the restful quality of the baby's sleep. Adequate rest is essential for a developing child. In turn, interruptions to a healthy sleep cycle can cause serious detriments to the baby, including such dangers as fetal alcohol syndrome (3) .
Alcohol affects the ways humans sleep. Even a small drink six hours before bed interferes with the resting process. The dangers and side effects of disrupted sleep increase with alcohol abuse, and some sleep problems may lead to alcoholism, or serve as an excuse for a recovering alcoholic's relapse. These negative effects of alcohol on sleep can extend even to small children by way of their mother. It's best to be aware of these risks before overindulging in alcohol, especially if one has a condition such as sleep apnea, which may be aggravated by alcohol, sometimes with fatal results.
1)Alcohol's Effects on Sleep in Alcoholics,
3)No Thanks, I'm Sleeping,
4)Drinking the Night Away,
5)Kentucky Sleep Society,
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