Everyone is aware of the importance of sleep for their well-being, even if they do not know the specifics of how sleep functions. Lack of sleep results in a number of problems including daytime sleepiness, short term memory problems, difficulty with attention and concentration and low energy. Extended sleep deprivation can result in confusion, perceptual alterations and even psychotic symptoms. Sleep also has an important role in physical health. Sleep bolster the immune system and inadequate sleep across a period can result in your body’s inability to repair itself in an efficient manner. It’s not an accident that the most common advice given to people who are ill or injured is to get as much rest as possible. Sleep deprivation can increase risk of having a heart attack or stroke and developing kidney disease, high blood pressure and diabetes. Sleep plays a critical role in puberty and fertility and triggers the release of growth hormone which is important in childhood growth and adulthood development of muscle mass (Centers for Disease Control and Prevention, 2009).
Those who keep irregular schedules, eat late at night or go to bed much later on their days off than on work nights often have difficulty getting to sleep, staying asleep or sleeping late enough in the mornings. Sleep problems are also associated with using the bed and bedroom for work, watching T.V. or movies or activities other than sleep. Anxiety and other mental health concerns or the tendency to ruminate about the events of the day can also interfere with sleep. These problems are relatively common and can be fixed fairly easily (Harvard Health Publications, 2006). This ability to eliminate difficulties is contrary to sleep disorders in that sleep disorders usually require professional intervention to eliminate (DSM V, 2013).
When Sleep Problems Become a Sleep Disorder
According to the University of Maryland Medical Center (2014), the definition of a sleep disorder is, “Sleep disorders are problems with sleeping, including trouble falling or staying asleep, falling asleep at the wrong times, too much sleep, or abnormal behaviors during sleep”. Sleep disorders are diagnosed when the sleep problem causes distress to the individual or others (e.g. in the case of sleep-walking), or when it interferes with the individual’s ability to function normally in day to day activities. A disorder also refers to a problem that repeats as opposed to one that occurs on a single occasion (DSM-5, 2013). According to the International Classification of Sleep Disorders (ICSD 3) (2014), more than 80 different diagnosis exist for sleep disorders. However, a more useful approach is presented by the DSM 5 which puts similar disorders together under a single categorical heading. Additionally, sleep disorders are classified as primary or secondary. Primary means they are the main problem and he sleep disorder is not due to another cause such as drugs or a disease process. When sleep disorders occur as the result of another condition they are referred to as secondary sleep disorders. This paper will utilize the types as listed in the DSM 5 discussing only primary sleep disorders.
Sleep Disorders, now termed Sleep-Wake Disorders according to the DSM 5 classifies 10 separate categories of disorders. These disorders include:
- Hypersomnolence Disorder
- Breathing Related Sleep Disorders
- Circadian Rhythm Sleep Wake Disorders
- Non-Rapid Eye Movement Sleep Arousal Disorders (NREM)
- Rapid Eye Movement Sleep Behavior Disorder
- Restless Leg Syndrome
- Substance/Medication Induced Sleep Disorder
Substance/Medication Induced Sleep Disorder will not be discussed here as it is a secondary sleep disorder due to the effects of a substance or medication which is the primary cause.
It is important to note that sleep-wake disorders often occur with anxiety, depression and problems in the thought process which must also be categorized and treated for complete relief to occur. Additionally, sleep disturbances place an individual at risk for the development of other mental health disorders or substance abuse disorders (DSM 5, p. 361). Some of the more common sleep disorders are described below.
The primary complaint in someone with insomnia is not enough sleep or poor quality sleep accompanied by daytime sleepiness. This problems may involve the inability to fall asleep or to maintain sleep throughout the night. Different forms of insomnia can occur at different points in the sleep wake cycle. Initial insomnia and maintenance or middle insomnia involves trouble sleeping at bed time and trouble remaining asleep due to extended time awake between cycles during the night, respectively. Late insomnia or early morning awakenings involves awakening earlier than desired with the inability to fall back asleep. Six to ten percent of the population in this country suffer from insomnia at any one time. Insomnia can occur at any age but is more frequent in older adults and the elderly. The disorder is often episodic and related to stressful life events (Ferrie, Kumari, Salo, Singh-Manoux, & Kivimäki, 2011).
Hypersomnolence includes a wide range of difficulties including excessive amount of sleep, loss of quality of wakefulness or limited involuntary daytime sleep (the individual knows they are falling asleep differentiating it from narcolepsy), and sleep inertia (the inability to remain alert after waking up from sleep). During this time behavior may be inappropriate, the person may seem almost like they are sleep walking, and there is a decline in motor activity. Sometimes the individual performs automatic behavior with little or no memory of the behavior. The individual may sleep for as long as 9-10 hours but the sleep is non-restorative and the person has problems getting up in the morning. Excessive sleepiness results in napping throughout the day but again the sleep in non-restorative. Prevalence of this disorder is approximately 1 percent in the U.S. and the disorder occurs equally in men and women.
Narcolepsy can be a very disturbing disorder for individuals who suffer from it. This involves frequent, recurrent episodes irrepressible and sudden sleep episodes where the person drops off to sleep without warning. Narcolepsy often includes catoplexy or sudden episodes of loss of muscle tone which is triggered by strong emotions. Cataplexy episodes are generally brief and can include the any of the major muscle groups resulting in sudden head bobbing or falling. In children cataplexy is often atypical including facial muscles and resulting in grimacing, twisting of the mouth, tongue thrusting of mouth opening. These are referred to as cataplectic faces. Narcolepsy-catoplexy affects .02 percent to 04 percent of the population.
Breathing Related Sleep Disorders
This category of disorders includes sleep apnea which involves upper airway obstruction causing the total absence of oxygen intake lasting at least 10 seconds in duration. Sleep apnea is often accompanied by snoring, snorting, gasping and breathing pauses during sleep whereby the person may begin snoring stop suddenly then after 10 seconds start breathing again with a huge intake of air. Snoring and daytime sleepiness are the two most recognized symptoms of the disorder. Often obesity can lead to this as this disorder. This is a common disorder and it occurs in 1 percent to 2 percent of children and, 2 percent to 15 percent of middle age adults and over 20 percent of older adults.
Circadian Rhythm Sleep-Wake Disorders
The Delayed Sleep Phase Type of this disorder involves a delayed sleep phase of at least two hours with resulting in insomnia, difficulty waking in the morning and daytime sleepiness. Early morning confusion is also common. This disorder is usually due to altered schedules which cause delayed sleep. When people with this disorder are allowed to set their own sleep schedules they report getting enough sleep with good quality. While the prevalence rate in the general population is only .17 percent, prevalence rates in excess of 7 percent have been reported in adolescents.
The Advanced Sleep Phase Type of this disorder involves sleep wake times which are several hours ahead of when desired. Advanced time of sleep is of at least two hours. Even when they are able to delay their sleep time, people with this disorder will still wake earlier than usual. When allowed to set their own schedules people with this type of the disorder will sleep a normal amount of time and exhibit good sleep quality.
Irregular Sleep Wake Type involves a lack of a regular easily determinable sleep wake circadian rhythm. Individuals with this type of disorder have no regular sleep period and instead break their sleep up into at least three different periods during the day. This is a result of insomnia at night and daytime sleepiness. The longest sleep period usually occurs between 2:00am and 6:00am This schedule limits the type of work they can do and sometimes prevents them from working anything other than shift positions. The ability to attend school may also be affected.
Parasomnias involve abnormal behavior, experiences or physiology in association with different sleep phases or transitions. The most common type of parasomnia is Non-Rapid Eye Movement Sleep Arousal Disorder. This disorder is an unusual disorder in that it involves mixing states of wakefulness with sleep, both wakefulness mixed with NREM Sleep and wakefulness mixed with REM sleep. This may manifest in sleep walking or sleep terrors.
Sleep walking involves rising from bed during sleep and moving around. While sleep walking the person as their eyes open but has a glazed unseeing look in their eyes and a blank face. Although sleeping, it is rare that someone hurts themselves during sleepwalking as they can avoid obstacles as if seeing them in a waking state. Attempts to communicate with them may result in a response but if so it is nonsensical. Awakening a sleepwalker is very difficult. They do not remember the event the next day.
Sleep terrors involve being aroused from sleep in a state of terror. Usually relegated to childhood, the person awakens usually screaming and they possess autonomic signs of fear. These individuals are relatively unresponsive to efforts to wake them. When they awaken they do not report remembering anything that had frightened them or the occurrence of nightmares. They experience amnesia for the event similar to sleepwalkers.
Nighmare Disorder involves the repeated experience of extended dreams that are frightening, vivid and well-remembered, the worst sometimes remembered over a lifetime. When the person awakens from a nightmare the are quickly alert, aware of their surroundings and fully oriented. Nightmares tend to be more elaborate, story like or sequential and more easily understood than other dreams. Content usually involves attempts to avoid threats, danger or attempts to survive. Nightmares occur during the second half of the life. These types of dreams occur exclusively during REM sleep. The negative emotions that result may cause the individual enough distress that they are not able to go back to sleep and the distress may even continue into the daytime. Sometimes nightmare occur during sleep onset REM periods (a rare occurrence) in which case the person may experience hallucinations (hypnagogic hallucinations) characterized by a sense of being awake and unable to more (isolated sleep paralysis).
American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) (2013), American Psychiatric Association, Arlington, VA.
Centers for Disease Control and Prevention. (2009). Perceived insufficient rest or sleep among adults, Epidemiology Program Office. Morbidity and Mortality Weekly Report, 58(42), 1175-9.
Ferrie, J. E., Kumari, M., Salo, P., Singh-Manoux, A. and Kivimäki, M. (2011). Sleep epidemiology—a rapidly growing field. International Journal of Epidemiology, 40 (6), 1431-1437.
Harvard Health Publications. (2006). Importance of Sleep: Six reasons not to scrimp on sleep. Harvard Medical School. Retrieved from http://www.health.harvard.edu/press_releases/importance_of_sleep_and_health
International Classification of Sleep Disorders, 3rd ed, American Academy of Sleep Medicine, Darien, IL 2014.