Sleep medicine
Encyclopedia
Sleep medicine is a medical specialty or subspecialty
devoted to the diagnosis and therapy
of sleep
disturbances and disorders
. From the middle of the 20th century, research has provided increasing knowledge and answered many questions about sleep-wake functioning. The rapidly evolving field has become a recognized medical subspecialty in some countries. Dental sleep medicine also qualifies for board certification
in some countries. Properly organized, minimum 12-month, postgraduate training programs are still being defined in the United States. In some countries, the sleep researchers and the doctors who treat patients may be the same people.
The first sleep clinic
s in the United States were established in the 1970s by interested doctor
s and technician
s; the study, diagnosis
and treatment of obstructive sleep apnea
were their first tasks. As late as 1999, virtually any American doctor, with no specific training in sleep medicine, could open a sleep laboratory
.
Disorders and disturbances of sleep are widespread and can have significant consequences for affected individuals as well as economic and other consequences for society. The US National Transportation Safety Board has, according to Dr. Charles Czeisler
, member of the Institute of Medicine and Director of the Harvard University Medical School Division of Sleep Medicine at Brigham and Women's Hospital
, discovered that the leading cause of fatal-to-the-driver heavy truck crashes is fatigue-related (fatigue – 31%, alcohol and other drug use – 29%), and sleep deprivation
has been a significant factor in dramatic accidents, such as the Exxon Valdez oil spill
, the nuclear incidents at Chernobyl
and Three Mile Island
and the explosion of the space shuttle Challenger
.
s such as excessive daytime sleepiness
, which, in the absence of volitional sleep deprivation
, "is almost inevitably caused by an identifiable and treatable sleep disorder," such as sleep apnea, narcolepsy
, idiopathic central nervous system (CNS) hypersomnia
, Kleine-Levin syndrome
, menstrual-related hypersomnia, idiopathic
recurrent stupor, or circadian rhythm disturbances. Another common complaint is insomnia
, a set of symptoms that can have many causes, physical and mental. Management in the varying situations differs greatly and cannot be undertaken without a correct diagnosis.
ICSD, The International Classification of Sleep Disorders
, was restructured in 1990, in relation to its predecessor, to include only one code for each diagnostic entry and to classify disorders by pathophysiologic mechanism, as far as possible, rather than by primary complaint. Training in sleep medicine is multidisciplinary, and the present structure was chosen to encourage a multidisciplinary approach to diagnosis. Sleep disorders often do not fit neatly into traditional classification; differential diagnoses cross medical systems. Minor revisions and updates to the ICSD were made in 1997 and in following years. The present classification system in fact follows the groupings suggested by Nathaniel Kleitman
, the "father of sleep research," in his seminal 1939 book Sleep and Wakefulness.
The revised ICSD, ICSD-R, placed the primary sleep disorders in the subgroups (1) dyssomnias, which include those that produce complaints of insomnia or excessive sleepiness, and (2) the parasomnias, which do not produce those primary complaints but intrude into or occur during sleep. A further subdivision of the dyssomnias preserves the integrity of circadian rhythm sleep disorders, as was mandated by about 200 doctors and researchers from all over the world who participated in the process between 1985–1990. The last two subgroups were (3) the medical or psychiatric sleep disorder section and (4) the proposed new disorders section. The authors found the heading "medical or psychiatric" less than ideal but better than the alternative "organic or non-organic," which seemed more likely to change in the future. Detailed reporting schemes aimed to provide data for further research. A second edition, called ICSD-2, was published in 2005.
MeSH, Medical Subject Headings
, a service of the US National Library of Medicine and the National Institutes of Health, uses similar broad categories: (1) dyssomnias, including narcolepsy, apnea, and the circadian rhythm sleep disorders, (2) parasomnias, which include, among others, bruxism
(tooth-grinding), sleepwalking
and bedwetting
, and (3) sleep disorders caused by medical or psychiatric conditions. The system used produces "trees," approaching each diagnosis from up to several angles such that each disorder may be known by several codes.
DSM-IV-TR, the Diagnostic and Statistical Manual of Mental Disorders
, Fourth Edition, Text Revision, using the same diagnostic codes as the International Statistical Classification of Diseases and Related Health Problems (ICD), divides sleep disorders into three groups: (1) primary sleep disorders, both the dyssomnias and the parasomnias, presumed to result from an endogenous disturbance in sleep-wake generating or timing mechanisms, (2) those secondary to mental disorders and (3) those related to a general medical condition or substance abuse.
Recent thinking opens for a common cause for mood
and sleep disorders occurring in the same patient; a 2010 review states that, in humans, "single nucleotide polymorphisms in Clock and other clock genes have been associated with depression" and that the "evidence that mood disorders are associated with disrupted or at least inappropriately timed circadian rhythms suggests that treatment strategies or drugs aimed at restoring 'normal' circadian rhythmicity may be clinically useful."
sleep in a variety of patterns; seldom do they resemble our modern habit of sleeping in one single eight-hour bout. Much has been written about dream interpretation
, from biblical times to Freud
, but sleep itself was historically seen as a passive state of not-awake.
The concept of sleep medicine belongs to the second half of the 20th century. Due to the rapidly increasing knowledge about sleep, including the growth of the research field chronobiology
from about 1960 and the discoveries of REM sleep (1952–53) and sleep apnea (first described in the medical literature in 1965), the medical importance of sleep was recognized. The medical community began paying more attention than previously to primary sleep disorders, such as sleep apnea, as well as the role and quality of sleep in other conditions. By the 1970s in the US, and in many western nations within the two following decades, clinics and laboratories devoted to the study of sleep and the treatment of its disorders had been founded. Most sleep doctors were primarily concerned with apnea; some were experts in narcolepsy. There was as yet nothing to restrict the use of the title "sleep doctor," and a need for standards arose.
Basic medical training has paid little attention to sleep problems; according to Benca in her review
Diagnosis and Treatment of Chronic Insomnia (2005), most doctors are "not well trained with respect to sleep and sleep disorders," and a survey in 1990–91 of 37 American medical school
s showed that sleep and sleep disorders were "covered" in less than two (2) hours of total teaching time, on average. Benca's review cites a 2002 survey by Papp et al. of more than 500 primary care physician
s who self-reported their knowledge of sleep disorders as follows: Excellent – 0%; Good – 10%, Fair – 60%; and Poor – 30%. The review of more than 50 studies indicates that both doctors and patient
s appear reluctant to discuss sleep complaints, in part because of perceptions that treatments for insomnia are ineffective or associated with risks, and:
Also, an editorial in the American College of Chest Physicians' (pulmonologists') journal CHEST in 1999 was quite concerned about the Conundrums in Sleep Medicine. The author, then chair of her organization's Sleep Section, asked "What is required to set up a sleep laboratory? Money and a building! Anyone can open a sleep laboratory, and it seems that just about everyone is." On the accreditation
process for sleep laboratories, she continues: "This accreditation, however, is currently not required by most states, or more importantly, by most insurance
carriers for reimbursements... There is also an American Board of Sleep Medicine (ABSM) that certifies individuals as sleep specialists. This certification presumably makes those individuals more qualified to run a sleep laboratory; however, the certification is not required to run a laboratory or to read sleep studies." Her concern at the turn of the century was:
In the UK, knowledge of sleep medicine and possibilities for diagnosis and treatment seem to lag. Guardian.co.uk quotes the director of the Imperial College Healthcare
Sleep Centre: "One problem is that there has been relatively little training in sleep medicine in this country – certainly there is no structured training for sleep physicians." The Imperial College Healthcare site shows attention to obstructive sleep apnea syndrome (OSA) and very few other disorders, specifically not including insomnia.
(AASM), the Sleep Research Society
of the United States (SRS), the Canadian Sleep Society
(CSS) and the Federation of Latin American Sleep Societies (FLASS). WFSRSMS publishes the Journal of Sleep Research, the Journal of Clinical Sleep Medicine, SLEEP and Sleep and Biological Rhythms and promotes both sleep research and physician training and education.
surgeons, pulmonologists, cardiologists, endocrinologists and psychiatrists.
The American Academy of Sleep Medicine
(AASM), founded in 1978, administered the certification process and sleep medicine examination for doctors until 1990. Its independent daughter entity the American Board of Sleep Medicine
(ABSM) was incorporated in 1991 and took over the aforementioned responsibilities. As of 2007, the ABSM ceased administering its examination, as it conceded that an examination process recognized by the American Board of Medical Specialties
(ABMS) was advantageous to the field. Candidates who passed the ABSM exam in 1978–2006 retain lifetime certification as Diplomates of that organization.
The American Board of Psychiatry and Neurology
(ABPN), and the corresponding boards of Internal Medicine, of Pediatrics, and of Otolaryngology (ear, nose and throat, ENT) now administer collectively the Sleep Medicine Certification exam for their members. Each board supervises the required 12 months of formal training for its candidates, while the exam is administered to all of them at the same time in the same place. For the first five years, 2007–2011, during "grandfathering," there is a "practice pathway" for ABSM certified specialists. Additional, coordinated requirements are to be added after 2011. The ABPN provides information about the pathways, requirements and the exam on its website.
Sleep medicine is now a recognized subspecialty within anesthesiology, internal medicine
, family medicine
, pediatrics
, otolaryngology
, psychiatry
and neurology
in the US. Certification in Sleep Medicine by the several "Member Boards" of the ABMS shows that the specialist:
Pulmonologists, already subspecialists within internal medicine, may be accepted to sit for the board and be certified in Sleep Medicine after just a six-month fellowship
, building on their knowledge of sleep-related breathing problems, rather than the usual twelve-month fellowship required of other specialists.
Sleep dentistry (bruxism
, snoring and sleep apnea), while not recognized as one of the nine dental specialties
, qualifies for board-certification by the American Board of Dental Sleep Medicine (ABDSM). The resulting Diplomate status is recognized by the AASM, and these dentists are organized in the Academy of Dental Sleep Medicine (USA). The qualified dentists collaborate with sleep doctors at accredited sleep centers and can provide several types of oral appliances
or upper airway surgery to treat or manage sleep-related breathing disorders as well as tooth-grinding and clenching.
Laboratories for sleep-related breathing disorders are accredited by the AASM, and are required to follow the Code of Medical Ethics of the American Medical Association. The new and very detailed Standards for Accreditation are available online. Sleep disorder centers, or clinics, are accredited by the same body, whether hospital-based, university-based or "freestanding"; they are required to provide testing and treatment for all sleep disorders and to have on staff a sleep specialist who has been certified by the American Board of Sleep Medicine and otherwise meet similar standards.
The taking of a thorough medical history
while keeping in mind alternative diagnoses
and the possibility of more than one ailment in the same patient is the first step. Symptoms for very different sleep disorders may be similar and it must be determined whether any psychiatric problems are primary or secondary.
The patient history includes previous attempts at treatment and coping and a careful medication review. Differentiation of transient from chronic disorders and primary from secondary ones influences the direction of evaluation and treatment plans.
The Epworth Sleepiness Scale
(ESS), designed to give an indication of sleepiness and correlated with sleep apnea, or other questionnaires designed to measure excessive daytime sleepiness
, are diagnostic tools that can be used repeatedly to measure results of treatment.
A sleep diary
, also called sleep log or sleep journal, kept by a patient at home for at least two weeks, while subjective, may help determine the extent and nature of sleep disturbance and the level of alertness in the normal environment. A parallel journal kept by a parent or bed partner, if any, can also be helpful. Sleep logs also can be used for self-monitoring and in connection with behavioral and other treatment. The image at the top of this page, with nighttime in the middle and the weekend in the middle, shows a layout that can aid in noticing trends
An actigraph unit is a motion-sensing device worn on the wrist, generally for one week. It gives a gross picture of sleep-wake cycles and is often used to verify the sleep diary. It is cost-efficient when full polysomnography is not required.
Polysomnography
is performed in a sleep laboratory while the patient sleeps, preferably at his or her usual sleeping time. The polysomnogram (PSG) objectively records sleep stages and respiratory events. It shows multiple channels of electroencephalogram (EEG), electrooculogram (EOG), electrocardiogram
(ECG), nasal and oral airflow, abdominal, chest and leg movements and blood oxygen levels. A single part of a polysomnogram is sometimes measured at home with portable equipment, for example oximetry, which records blood oxygen levels throughout the night. Polysomnography is not routinely used in the evaluation of patients with insomnia or circadian rhythm disorders, except as needed to rule out other disorders. It will usually be a definitive test for sleep apnea.
A Multiple Sleep Latency Test
(MSLT) is often performed during the entire day after polysomnography while the electrodes and other equipment are still in place. The patient is given nap opportunities every second hour; the test measures the number of minutes it takes from the start of a daytime nap period to the first signs of sleep. It is a measure of daytime sleepiness; it also shows whether REM sleep is achieved in a short nap, a typical indication of narcolepsy
.
Imaging studies
may be performed if a patient is to be evaluated for neurodegenerative disease or to determine the obstruction in obstructive sleep apnea.
When sleep complaints are secondary to pain, other medical or psychiatric diagnoses, or substance abuse, it may be necessary to treat both the underlying cause and the sleep problems.
When the underlying cause of sleep problems is not immediately obvious, behavioral treatments are usually the first suggested. These range from patient education
about sleep hygiene
to cognitive behavioral therapy (CBT). Studies of both younger and older adults have compared CBT to medication and found that CBT should be considered a first-line and cost-effective intervention for chronic insomnia, not least because gains may be maintained at long-term follow-up. Sleep physicians and psychologists, at least in the US, are not in agreement about who should perform CBT nor whether sleep centers should be required to have psychologists on staff. Behavioral therapies include progressive relaxation, stimulus control (to reassociate the bed with sleepiness), limiting time-in-bed to increase sleep efficiency and debunking misconceptions about sleep.
Pharmacology
is necessary for some conditions. Medication may be useful for acute insomnia and for some of the parasomnias. It is almost always needed, along with scheduled short naps and close follow-up, in the treatment of narcolepsy and idiopathic hypersomnia.
Chronic circadian rhythm disorders, the most common of which is delayed sleep phase disorder, may be managed by specifically timed bright light therapy
, timed oral administration of the hormone melatonin
, and/or chronotherapy
. Stimulants may also be prescribed. When these therapies are unsuccessful, counseling may be indicated to help a person adapt to and live with the condition. People with these disorders who have chosen a lifestyle in conformity with their sleeping schedules have no need of treatment, though they may need the diagnosis in order to avoid having to meet for appointments or meetings during their sleep time.
Continuous positive airway pressure
(CPAP) machines and oral appliances are used nightly at home to manage sleep-related breathing disorders such as apnea. In some cases, upper airway surgery generally performed by an otolaryngologist/head & neck surgeon or occasionally an oral and maxillofacial surgeon
is indicated. In mild cases in obese people, weight reduction may be sufficient. The treatments prevent airway collapse, which interrupts breathing during sleep.
Subspecialty
A subspecialty is narrow field within a specialty such as forensic pathology, which is a subspecialty of anatomical pathology. A subspecialist is a specialist of a subspecialty....
devoted to the diagnosis and therapy
Therapy
This is a list of types of therapy .* Adventure therapy* Animal-assisted therapy* Aquatic therapy* Aromatherapy* Art and dementia* Art therapy* Authentic Movement* Behavioral therapy* Bibliotherapy* Buteyko Method* Chemotherapy...
of sleep
Sleep
Sleep is a naturally recurring state characterized by reduced or absent consciousness, relatively suspended sensory activity, and inactivity of nearly all voluntary muscles. It is distinguished from quiet wakefulness by a decreased ability to react to stimuli, and is more easily reversible than...
disturbances and disorders
Sleep disorder
A sleep disorder, or somnipathy, is a medical disorder of the sleep patterns of a person or animal. Some sleep disorders are serious enough to interfere with normal physical, mental and emotional functioning...
. From the middle of the 20th century, research has provided increasing knowledge and answered many questions about sleep-wake functioning. The rapidly evolving field has become a recognized medical subspecialty in some countries. Dental sleep medicine also qualifies for board certification
Board certification
Board certification is the process by which a physician , dentist , or podiatrist in the United States demonstrates through either written, practical, and/or simulator based testing, a mastery of the basic knowledge and skills that define an area of medical specialization...
in some countries. Properly organized, minimum 12-month, postgraduate training programs are still being defined in the United States. In some countries, the sleep researchers and the doctors who treat patients may be the same people.
The first sleep clinic
Clinic
A clinic is a health care facility that is primarily devoted to the care of outpatients...
s in the United States were established in the 1970s by interested doctor
Physician
A physician is a health care provider who practices the profession of medicine, which is concerned with promoting, maintaining or restoring human health through the study, diagnosis, and treatment of disease, injury and other physical and mental impairments...
s and technician
Allied health professions
Allied health professions are clinical health care professions distinct from dentistry, nursing and medicine. One estimate reported allied health professionals make up 60 percent of the total health workforce...
s; the study, diagnosis
Diagnosis
Diagnosis is the identification of the nature and cause of anything. Diagnosis is used in many different disciplines with variations in the use of logics, analytics, and experience to determine the cause and effect relationships...
and treatment of obstructive sleep apnea
Sleep apnea
Sleep apnea is a sleep disorder characterized by abnormal pauses in breathing or instances of abnormally low breathing, during sleep. Each pause in breathing, called an apnea, can last from a few seconds to minutes, and may occur 5 to 30 times or more an hour. Similarly, each abnormally low...
were their first tasks. As late as 1999, virtually any American doctor, with no specific training in sleep medicine, could open a sleep laboratory
Laboratory
A laboratory is a facility that provides controlled conditions in which scientific research, experiments, and measurement may be performed. The title of laboratory is also used for certain other facilities where the processes or equipment used are similar to those in scientific laboratories...
.
Disorders and disturbances of sleep are widespread and can have significant consequences for affected individuals as well as economic and other consequences for society. The US National Transportation Safety Board has, according to Dr. Charles Czeisler
Charles Czeisler
Charles A. Czeisler is a researcher and author in the field of circadian rhythms and sleep medicine. He holds both an M.D. and a Ph.D. and is currently the Chief and Director of the Division of Sleep Medicine at Harvard Medical School and Brigham and Women's Hospital in Boston, MA, USA...
, member of the Institute of Medicine and Director of the Harvard University Medical School Division of Sleep Medicine at Brigham and Women's Hospital
Brigham and Women's Hospital
Brigham and Women's Hospital is the largest hospital of the Longwood Medical and Academic Area in Boston, Massachusetts. It is directly adjacent to Harvard Medical School of which it is the second largest teaching affiliate with 793 beds...
, discovered that the leading cause of fatal-to-the-driver heavy truck crashes is fatigue-related (fatigue – 31%, alcohol and other drug use – 29%), and sleep deprivation
Sleep deprivation
Sleep deprivation is the condition of not having enough sleep; it can be either chronic or acute. A chronic sleep-restricted state can cause fatigue, daytime sleepiness, clumsiness and weight loss or weight gain. It adversely affects the brain and cognitive function. Few studies have compared the...
has been a significant factor in dramatic accidents, such as the Exxon Valdez oil spill
Exxon Valdez oil spill
The Exxon Valdez oil spill occurred in Prince William Sound, Alaska, on March 24, 1989, when the Exxon Valdez, an oil tanker bound for Long Beach, California, struck Prince William Sound's Bligh Reef and spilled of crude oil. It is considered to be one of the most devastating human-caused...
, the nuclear incidents at Chernobyl
Chernobyl disaster
The Chernobyl disaster was a nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in Ukraine , which was under the direct jurisdiction of the central authorities in Moscow...
and Three Mile Island
Three Mile Island accident
The Three Mile Island accident was a core meltdown in Unit 2 of the Three Mile Island Nuclear Generating Station in Dauphin County, Pennsylvania near Harrisburg, United States in 1979....
and the explosion of the space shuttle Challenger
Space Shuttle Challenger
Space Shuttle Challenger was NASA's second Space Shuttle orbiter to be put into service, Columbia having been the first. The shuttle was built by Rockwell International's Space Transportation Systems Division in Downey, California...
.
Scope and classification
Competence in sleep medicine requires an understanding of a plethora of very diverse disorders, many of which present with similar symptomSymptom
A symptom is a departure from normal function or feeling which is noticed by a patient, indicating the presence of disease or abnormality...
s such as excessive daytime sleepiness
Excessive daytime sleepiness
Excessive daytime sleepiness is characterized by persistent sleepiness, and often a general lack of energy, even after apparently adequate night time sleep...
, which, in the absence of volitional sleep deprivation
Sleep deprivation
Sleep deprivation is the condition of not having enough sleep; it can be either chronic or acute. A chronic sleep-restricted state can cause fatigue, daytime sleepiness, clumsiness and weight loss or weight gain. It adversely affects the brain and cognitive function. Few studies have compared the...
, "is almost inevitably caused by an identifiable and treatable sleep disorder," such as sleep apnea, narcolepsy
Narcolepsy
Narcolepsy is a chronic sleep disorder, or dyssomnia, characterized by excessive sleepiness and sleep attacks at inappropriate times, such as while at work. People with narcolepsy often experience disturbed nocturnal sleep and an abnormal daytime sleep pattern, which often is confused with insomnia...
, idiopathic central nervous system (CNS) hypersomnia
Hypersomnia
Hypersomnia is a disorder characterized by excessive amounts of sleepiness.There are two main categories of hypersomnia: primary hypersomnia and recurrent hypersomnia...
, Kleine-Levin syndrome
Kleine-Levin syndrome
Kleine-Levin Syndrome or KLS is aneurological disorder characterized by recurring periods of excessive amounts of sleeping and eating. At the onset of an episode the patient becomes drowsy and sleeps for most of the day and night , waking only to eat or go to the bathroom...
, menstrual-related hypersomnia, idiopathic
Idiopathic
Idiopathic is an adjective used primarily in medicine meaning arising spontaneously or from an obscure or unknown cause. From Greek ἴδιος, idios + πάθος, pathos , it means approximately "a disease of its own kind". It is technically a term from nosology, the classification of disease...
recurrent stupor, or circadian rhythm disturbances. Another common complaint is insomnia
Insomnia
Insomnia is most often defined by an individual's report of sleeping difficulties. While the term is sometimes used in sleep literature to describe a disorder demonstrated by polysomnographic evidence of disturbed sleep, insomnia is often defined as a positive response to either of two questions:...
, a set of symptoms that can have many causes, physical and mental. Management in the varying situations differs greatly and cannot be undertaken without a correct diagnosis.
ICSD, The International Classification of Sleep Disorders
International Classification of Sleep Disorders
The International Classification of Sleep Disorders is "a primary diagnostic, epidemiological and coding resource for clinicians and researchers in the field of sleep and sleep medicine."...
, was restructured in 1990, in relation to its predecessor, to include only one code for each diagnostic entry and to classify disorders by pathophysiologic mechanism, as far as possible, rather than by primary complaint. Training in sleep medicine is multidisciplinary, and the present structure was chosen to encourage a multidisciplinary approach to diagnosis. Sleep disorders often do not fit neatly into traditional classification; differential diagnoses cross medical systems. Minor revisions and updates to the ICSD were made in 1997 and in following years. The present classification system in fact follows the groupings suggested by Nathaniel Kleitman
Nathaniel Kleitman
Nathaniel Kleitman was Professor Emeritus in Physiology at the University of Chicago. Author of the seminal 1939 book Sleep and Wakefulness, he is recognized as the father of American sleep research...
, the "father of sleep research," in his seminal 1939 book Sleep and Wakefulness.
The revised ICSD, ICSD-R, placed the primary sleep disorders in the subgroups (1) dyssomnias, which include those that produce complaints of insomnia or excessive sleepiness, and (2) the parasomnias, which do not produce those primary complaints but intrude into or occur during sleep. A further subdivision of the dyssomnias preserves the integrity of circadian rhythm sleep disorders, as was mandated by about 200 doctors and researchers from all over the world who participated in the process between 1985–1990. The last two subgroups were (3) the medical or psychiatric sleep disorder section and (4) the proposed new disorders section. The authors found the heading "medical or psychiatric" less than ideal but better than the alternative "organic or non-organic," which seemed more likely to change in the future. Detailed reporting schemes aimed to provide data for further research. A second edition, called ICSD-2, was published in 2005.
MeSH, Medical Subject Headings
Medical Subject Headings
Medical Subject Headings is a comprehensive controlled vocabulary for the purpose of indexing journal articles and books in the life sciences; it can also serve as a thesaurus that facilitates searching...
, a service of the US National Library of Medicine and the National Institutes of Health, uses similar broad categories: (1) dyssomnias, including narcolepsy, apnea, and the circadian rhythm sleep disorders, (2) parasomnias, which include, among others, bruxism
Bruxism
Bruxism is characterized by the grinding of the teeth and typically includes the clenching of the jaw. It is an oral parafunctional activity that occurs in most humans at some time in their lives. In most people, bruxism is mild enough not to be a health problem...
(tooth-grinding), sleepwalking
Sleepwalking
Sleepwalking, also known as somnambulism, is a sleep disorder belonging to the parasomnia family. Sleepwalkers arise from the slow wave sleep stage in a state of low consciousness and perform activities that are usually performed during a state of full consciousness...
and bedwetting
Bedwetting
Nocturnal enuresis, commonly called bedwetting, is involuntary urination while asleep after the age at which bladder control usually occurs. Nocturnal enuresis is considered primary when a child has not yet had a prolonged period of being dry...
, and (3) sleep disorders caused by medical or psychiatric conditions. The system used produces "trees," approaching each diagnosis from up to several angles such that each disorder may be known by several codes.
DSM-IV-TR, the Diagnostic and Statistical Manual of Mental Disorders
Diagnostic and Statistical Manual of Mental Disorders
The Diagnostic and Statistical Manual of Mental Disorders is published by the American Psychiatric Association and provides a common language and standard criteria for the classification of mental disorders...
, Fourth Edition, Text Revision, using the same diagnostic codes as the International Statistical Classification of Diseases and Related Health Problems (ICD), divides sleep disorders into three groups: (1) primary sleep disorders, both the dyssomnias and the parasomnias, presumed to result from an endogenous disturbance in sleep-wake generating or timing mechanisms, (2) those secondary to mental disorders and (3) those related to a general medical condition or substance abuse.
Recent thinking opens for a common cause for mood
Depression (mood)
Depression is a state of low mood and aversion to activity that can affect a person's thoughts, behaviour, feelings and physical well-being. Depressed people may feel sad, anxious, empty, hopeless, helpless, worthless, guilty, irritable, or restless...
and sleep disorders occurring in the same patient; a 2010 review states that, in humans, "single nucleotide polymorphisms in Clock and other clock genes have been associated with depression" and that the "evidence that mood disorders are associated with disrupted or at least inappropriately timed circadian rhythms suggests that treatment strategies or drugs aimed at restoring 'normal' circadian rhythmicity may be clinically useful."
History
A 16th-century physician wrote that many laborers dozed off exhausted at the start of each night; sexual intercourse with their wives typically occurring in the watching period, after a recuperative first sleep. Anthropologists find that isolated societies without electric lightElectric light
Electric lights are a convenient and economic form of artificial lighting which provide increased comfort, safety and efficiency. Most electric lighting is powered by centrally-generated electric power, but lighting may also be powered by mobile or standby electric generators or battery systems...
sleep in a variety of patterns; seldom do they resemble our modern habit of sleeping in one single eight-hour bout. Much has been written about dream interpretation
Dream interpretation
Dream interpretation is the process of assigning meaning to dreams. In many ancient societies, such as those of Egypt and Greece, dreaming was considered a supernatural communication or a means of divine intervention, whose message could be unravelled by people with certain powers...
, from biblical times to Freud
Sigmund Freud
Sigmund Freud , born Sigismund Schlomo Freud , was an Austrian neurologist who founded the discipline of psychoanalysis...
, but sleep itself was historically seen as a passive state of not-awake.
The concept of sleep medicine belongs to the second half of the 20th century. Due to the rapidly increasing knowledge about sleep, including the growth of the research field chronobiology
Chronobiology
Chronobiology is a field of biology that examines periodic phenomena in living organisms and their adaptation to solar- and lunar-related rhythms. These cycles are known as biological rhythms. Chronobiology comes from the ancient Greek χρόνος , and biology, which pertains to the study, or science,...
from about 1960 and the discoveries of REM sleep (1952–53) and sleep apnea (first described in the medical literature in 1965), the medical importance of sleep was recognized. The medical community began paying more attention than previously to primary sleep disorders, such as sleep apnea, as well as the role and quality of sleep in other conditions. By the 1970s in the US, and in many western nations within the two following decades, clinics and laboratories devoted to the study of sleep and the treatment of its disorders had been founded. Most sleep doctors were primarily concerned with apnea; some were experts in narcolepsy. There was as yet nothing to restrict the use of the title "sleep doctor," and a need for standards arose.
Basic medical training has paid little attention to sleep problems; according to Benca in her review
Review
A review is an evaluation of a publication, a product or a service, such as a movie , video game, musical composition , book ; a piece of hardware like a car, home appliance, or computer; or an event or performance, such as a live music concert, a play, musical theater show or dance show...
Diagnosis and Treatment of Chronic Insomnia (2005), most doctors are "not well trained with respect to sleep and sleep disorders," and a survey in 1990–91 of 37 American medical school
Medical school
A medical school is a tertiary educational institution—or part of such an institution—that teaches medicine. Degree programs offered at medical schools often include Doctor of Osteopathic Medicine, Bachelor/Doctor of Medicine, Doctor of Philosophy, master's degree, or other post-secondary...
s showed that sleep and sleep disorders were "covered" in less than two (2) hours of total teaching time, on average. Benca's review cites a 2002 survey by Papp et al. of more than 500 primary care physician
Primary care physician
A primary care physician, or PCP, is a physician/medical doctor who provides both the first contact for a person with an undiagnosed health concern as well as continuing care of varied medical conditions, not limited by cause, organ system, or diagnosis....
s who self-reported their knowledge of sleep disorders as follows: Excellent – 0%; Good – 10%, Fair – 60%; and Poor – 30%. The review of more than 50 studies indicates that both doctors and patient
Patient
A patient is any recipient of healthcare services. The patient is most often ill or injured and in need of treatment by a physician, advanced practice registered nurse, veterinarian, or other health care provider....
s appear reluctant to discuss sleep complaints, in part because of perceptions that treatments for insomnia are ineffective or associated with risks, and:
Also, an editorial in the American College of Chest Physicians' (pulmonologists') journal CHEST in 1999 was quite concerned about the Conundrums in Sleep Medicine. The author, then chair of her organization's Sleep Section, asked "What is required to set up a sleep laboratory? Money and a building! Anyone can open a sleep laboratory, and it seems that just about everyone is." On the accreditation
Accreditation
Accreditation is a process in which certification of competency, authority, or credibility is presented.Organizations that issue credentials or certify third parties against official standards are themselves formally accredited by accreditation bodies ; hence they are sometimes known as "accredited...
process for sleep laboratories, she continues: "This accreditation, however, is currently not required by most states, or more importantly, by most insurance
Insurance
In law and economics, insurance is a form of risk management primarily used to hedge against the risk of a contingent, uncertain loss. Insurance is defined as the equitable transfer of the risk of a loss, from one entity to another, in exchange for payment. An insurer is a company selling the...
carriers for reimbursements... There is also an American Board of Sleep Medicine (ABSM) that certifies individuals as sleep specialists. This certification presumably makes those individuals more qualified to run a sleep laboratory; however, the certification is not required to run a laboratory or to read sleep studies." Her concern at the turn of the century was:
In the UK, knowledge of sleep medicine and possibilities for diagnosis and treatment seem to lag. Guardian.co.uk quotes the director of the Imperial College Healthcare
Imperial College Healthcare NHS Trust
Imperial College Healthcare NHS Trust is an NHS trust based in London, United Kingdom. It is the largest NHS trust in England and together with Imperial College London forms an academic health science centre....
Sleep Centre: "One problem is that there has been relatively little training in sleep medicine in this country – certainly there is no structured training for sleep physicians." The Imperial College Healthcare site shows attention to obstructive sleep apnea syndrome (OSA) and very few other disorders, specifically not including insomnia.
Worldwide
The World Federation of Sleep Research & Sleep Medicine Societies (WFSRSMS) was founded in 1987. As its name implies, members are concerned with basic and clinical research as well as medicine. Member societies in the Americas are the American Academy of Sleep MedicineAmerican Academy of Sleep Medicine
The American Academy of Sleep Medicine is a United States professional society for the medical subspecialty of sleep medicine. It was established in 1975. The AASM is the only professional society that is dedicated exclusively to the medical subspecialty of sleep medicine...
(AASM), the Sleep Research Society
Sleep Research Society
The Sleep Research Society is an organization that promotes the science of sleep and related disorders. Additionally, the SRS is dedicated to the training and education of future sleep researchers.-Organization:...
of the United States (SRS), the Canadian Sleep Society
Canadian Sleep Society
The Canadian Sleep Society / Société Canadienne du Sommeil is a professional organization who's membership is made up primarily of sleep medicine practitioners, sleep researchers, polysomnographic technicians and students.-Description:...
(CSS) and the Federation of Latin American Sleep Societies (FLASS). WFSRSMS publishes the Journal of Sleep Research, the Journal of Clinical Sleep Medicine, SLEEP and Sleep and Biological Rhythms and promotes both sleep research and physician training and education.
Africa
The Colleges of Medicine of South Africa (CMSA) provide the well-defined specialty Diploma in Sleep Medicine of the College of Neurologists of South Africa: DSM(SA), which was first promulgated by the Health Professions Council in 2007. The newly formed South African Society of Sleep Medicine (SASSM) was launched at its inaugural congress in February 2010. The society's membership is diverse; it includes general practitioners, ENTOtolaryngology
Otolaryngology or ENT is the branch of medicine and surgery that specializes in the diagnosis and treatment of ear, nose, throat, and head and neck disorders....
surgeons, pulmonologists, cardiologists, endocrinologists and psychiatrists.
Asia
WFSRSMS members in Asia include the Australasian Sleep Association (ASA) of New Zealand and Australia and the Asian Sleep Research Society (ASRS), an umbrella organization for the societies of several Asian nations.Europe
The European Sleep Research Society (ESRS) is a member of the WFSRSMS. The Assembly of National Sleep Societies (ANSS), which includes both medical and scientific organizations from 26 countries as of 2007, is a formal body of the ESRS. The ESRS has published European Accreditation Guidelines for SMCs (Sleep Medicine Centres), the first of several proposed guidelines to coordinate and promote sleep science and medicine in Europe.United States
American Academy of Sleep Medicine
The American Academy of Sleep Medicine is a United States professional society for the medical subspecialty of sleep medicine. It was established in 1975. The AASM is the only professional society that is dedicated exclusively to the medical subspecialty of sleep medicine...
(AASM), founded in 1978, administered the certification process and sleep medicine examination for doctors until 1990. Its independent daughter entity the American Board of Sleep Medicine
American Board of Sleep Medicine
The American Board of Sleep Medicine says in its website, "The [ABSM] is an independent, nonprofit organization whose certifications are recognized throughout the world as a credential signifying a high level of competence for sleep medicine physicians, PhDs, behavioral sleep medicine specialists...
(ABSM) was incorporated in 1991 and took over the aforementioned responsibilities. As of 2007, the ABSM ceased administering its examination, as it conceded that an examination process recognized by the American Board of Medical Specialties
American Board of Medical Specialties
The American Board of Medical Specialties is a non-profit physician-led umbrella organization for 24 of the 26 approved medical specialty boards in the United States...
(ABMS) was advantageous to the field. Candidates who passed the ABSM exam in 1978–2006 retain lifetime certification as Diplomates of that organization.
The American Board of Psychiatry and Neurology
American Board of Psychiatry and Neurology
The American Board of Psychiatry and Neurology, Inc. is a nonprofit corporation that was founded in 1934 following conferences of committees appointed by the American Psychiatric Association, the American Neurological Association, and the then Section on Nervous and Mental Diseases of the American...
(ABPN), and the corresponding boards of Internal Medicine, of Pediatrics, and of Otolaryngology (ear, nose and throat, ENT) now administer collectively the Sleep Medicine Certification exam for their members. Each board supervises the required 12 months of formal training for its candidates, while the exam is administered to all of them at the same time in the same place. For the first five years, 2007–2011, during "grandfathering," there is a "practice pathway" for ABSM certified specialists. Additional, coordinated requirements are to be added after 2011. The ABPN provides information about the pathways, requirements and the exam on its website.
Sleep medicine is now a recognized subspecialty within anesthesiology, internal medicine
Internal medicine
Internal medicine is the medical specialty dealing with the prevention, diagnosis, and treatment of adult diseases. Physicians specializing in internal medicine are called internists. They are especially skilled in the management of patients who have undifferentiated or multi-system disease processes...
, family medicine
Family medicine
Family medicine is a medical specialty devoted to comprehensive health care for people of all ages. It is a division of primary care that provides continuing and comprehensive health care for the individual and family across all ages, sexes, diseases, and parts of the body...
, pediatrics
Pediatrics
Pediatrics or paediatrics is the branch of medicine that deals with the medical care of infants, children, and adolescents. A medical practitioner who specializes in this area is known as a pediatrician or paediatrician...
, otolaryngology
Otolaryngology
Otolaryngology or ENT is the branch of medicine and surgery that specializes in the diagnosis and treatment of ear, nose, throat, and head and neck disorders....
, psychiatry
Psychiatry
Psychiatry is the medical specialty devoted to the study and treatment of mental disorders. These mental disorders include various affective, behavioural, cognitive and perceptual abnormalities...
and neurology
Neurology
Neurology is a medical specialty dealing with disorders of the nervous system. Specifically, it deals with the diagnosis and treatment of all categories of disease involving the central, peripheral, and autonomic nervous systems, including their coverings, blood vessels, and all effector tissue,...
in the US. Certification in Sleep Medicine by the several "Member Boards" of the ABMS shows that the specialist:
Pulmonologists, already subspecialists within internal medicine, may be accepted to sit for the board and be certified in Sleep Medicine after just a six-month fellowship
Fellowship (medicine)
A fellowship is the period of medical training in the United States and Canada that a physician may undertake after completing a specialty training program . During this time , the physician is known as a fellow...
, building on their knowledge of sleep-related breathing problems, rather than the usual twelve-month fellowship required of other specialists.
Sleep dentistry (bruxism
Bruxism
Bruxism is characterized by the grinding of the teeth and typically includes the clenching of the jaw. It is an oral parafunctional activity that occurs in most humans at some time in their lives. In most people, bruxism is mild enough not to be a health problem...
, snoring and sleep apnea), while not recognized as one of the nine dental specialties
Dentistry
Dentistry is the branch of medicine that is involved in the study, diagnosis, prevention, and treatment of diseases, disorders and conditions of the oral cavity, maxillofacial area and the adjacent and associated structures and their impact on the human body. Dentistry is widely considered...
, qualifies for board-certification by the American Board of Dental Sleep Medicine (ABDSM). The resulting Diplomate status is recognized by the AASM, and these dentists are organized in the Academy of Dental Sleep Medicine (USA). The qualified dentists collaborate with sleep doctors at accredited sleep centers and can provide several types of oral appliances
Mandibular advancement splint
A mandibular splint or mandibular advancement splint is a device worn in the mouth that is used to treat obstructive sleep apnea and snoring...
or upper airway surgery to treat or manage sleep-related breathing disorders as well as tooth-grinding and clenching.
Laboratories for sleep-related breathing disorders are accredited by the AASM, and are required to follow the Code of Medical Ethics of the American Medical Association. The new and very detailed Standards for Accreditation are available online. Sleep disorder centers, or clinics, are accredited by the same body, whether hospital-based, university-based or "freestanding"; they are required to provide testing and treatment for all sleep disorders and to have on staff a sleep specialist who has been certified by the American Board of Sleep Medicine and otherwise meet similar standards.
Diagnostic methods
Medical history
The medical history or anamnesis of a patient is information gained by a physician by asking specific questions, either of the patient or of other people who know the person and can give suitable information , with the aim of obtaining information useful in formulating a diagnosis and providing...
while keeping in mind alternative diagnoses
Medical diagnosis
Medical diagnosis refers both to the process of attempting to determine or identify a possible disease or disorder , and to the opinion reached by this process...
and the possibility of more than one ailment in the same patient is the first step. Symptoms for very different sleep disorders may be similar and it must be determined whether any psychiatric problems are primary or secondary.
The patient history includes previous attempts at treatment and coping and a careful medication review. Differentiation of transient from chronic disorders and primary from secondary ones influences the direction of evaluation and treatment plans.
The Epworth Sleepiness Scale
Epworth Sleepiness Scale
The Epworth Sleepiness Scale is a scale intended to measure daytime sleepiness that is measured by use of a very short questionnaire. This can be helpful in diagnosing sleep disorders...
(ESS), designed to give an indication of sleepiness and correlated with sleep apnea, or other questionnaires designed to measure excessive daytime sleepiness
Excessive daytime sleepiness
Excessive daytime sleepiness is characterized by persistent sleepiness, and often a general lack of energy, even after apparently adequate night time sleep...
, are diagnostic tools that can be used repeatedly to measure results of treatment.
A sleep diary
Sleep diary
A sleep diary is a record of an individual's sleeping and waking times with related information, usually over a period of several weeks. It is self-reported or can be recorded by a care-giver....
, also called sleep log or sleep journal, kept by a patient at home for at least two weeks, while subjective, may help determine the extent and nature of sleep disturbance and the level of alertness in the normal environment. A parallel journal kept by a parent or bed partner, if any, can also be helpful. Sleep logs also can be used for self-monitoring and in connection with behavioral and other treatment. The image at the top of this page, with nighttime in the middle and the weekend in the middle, shows a layout that can aid in noticing trends
An actigraph unit is a motion-sensing device worn on the wrist, generally for one week. It gives a gross picture of sleep-wake cycles and is often used to verify the sleep diary. It is cost-efficient when full polysomnography is not required.
Polysomnography
Polysomnography
Polysomnography , also known as a sleep study, is a multi-parametric test used in the study of sleep and as a diagnostic tool in sleep medicine. The test result is called a polysomnogram, also abbreviated PSG...
is performed in a sleep laboratory while the patient sleeps, preferably at his or her usual sleeping time. The polysomnogram (PSG) objectively records sleep stages and respiratory events. It shows multiple channels of electroencephalogram (EEG), electrooculogram (EOG), electrocardiogram
Electrocardiogram
Electrocardiography is a transthoracic interpretation of the electrical activity of the heart over a period of time, as detected by electrodes attached to the outer surface of the skin and recorded by a device external to the body...
(ECG), nasal and oral airflow, abdominal, chest and leg movements and blood oxygen levels. A single part of a polysomnogram is sometimes measured at home with portable equipment, for example oximetry, which records blood oxygen levels throughout the night. Polysomnography is not routinely used in the evaluation of patients with insomnia or circadian rhythm disorders, except as needed to rule out other disorders. It will usually be a definitive test for sleep apnea.
A Multiple Sleep Latency Test
Multiple Sleep Latency Test
The Multiple Sleep Latency Test is a sleep disorder diagnostic tool. It is used to measure the time elapsed from the start of a daytime nap period to the first signs of sleep, called sleep latency...
(MSLT) is often performed during the entire day after polysomnography while the electrodes and other equipment are still in place. The patient is given nap opportunities every second hour; the test measures the number of minutes it takes from the start of a daytime nap period to the first signs of sleep. It is a measure of daytime sleepiness; it also shows whether REM sleep is achieved in a short nap, a typical indication of narcolepsy
Narcolepsy
Narcolepsy is a chronic sleep disorder, or dyssomnia, characterized by excessive sleepiness and sleep attacks at inappropriate times, such as while at work. People with narcolepsy often experience disturbed nocturnal sleep and an abnormal daytime sleep pattern, which often is confused with insomnia...
.
Imaging studies
Medical imaging
Medical imaging is the technique and process used to create images of the human body for clinical purposes or medical science...
may be performed if a patient is to be evaluated for neurodegenerative disease or to determine the obstruction in obstructive sleep apnea.
Treatments
When the underlying cause of sleep problems is not immediately obvious, behavioral treatments are usually the first suggested. These range from patient education
Patient education
Patient education is the process by which health professionals and others impart information to patients that will alter their health behaviors or improve their health status...
about sleep hygiene
Sleep hygiene
Sleep hygiene can be defined as the controlling of "all behavioural and environmental factors that precede sleep and may interfere with sleep." It is the practice of following guidelines in an attempt to ensure more restful, effective sleep which can promote daytime alertness and help treat or...
to cognitive behavioral therapy (CBT). Studies of both younger and older adults have compared CBT to medication and found that CBT should be considered a first-line and cost-effective intervention for chronic insomnia, not least because gains may be maintained at long-term follow-up. Sleep physicians and psychologists, at least in the US, are not in agreement about who should perform CBT nor whether sleep centers should be required to have psychologists on staff. Behavioral therapies include progressive relaxation, stimulus control (to reassociate the bed with sleepiness), limiting time-in-bed to increase sleep efficiency and debunking misconceptions about sleep.
Pharmacology
Pharmacology
Pharmacology is the branch of medicine and biology concerned with the study of drug action. More specifically, it is the study of the interactions that occur between a living organism and chemicals that affect normal or abnormal biochemical function...
is necessary for some conditions. Medication may be useful for acute insomnia and for some of the parasomnias. It is almost always needed, along with scheduled short naps and close follow-up, in the treatment of narcolepsy and idiopathic hypersomnia.
Chronic circadian rhythm disorders, the most common of which is delayed sleep phase disorder, may be managed by specifically timed bright light therapy
Light therapy
Light therapy or phototherapy consists of exposure to daylight or to specific wavelengths of light using lasers, light-emitting diodes, fluorescent lamps, dichroic lamps or very bright, full-spectrum light, usually controlled with various devices...
, timed oral administration of the hormone melatonin
Melatonin
Melatonin , also known chemically as N-acetyl-5-methoxytryptamine, is a naturally occurring compound found in animals, plants, and microbes...
, and/or chronotherapy
Chronotherapy
People who suffer from delayed sleep phase syndrome are generally unable to reset their circadian rhythm by moving their bedtime and rising time earlier...
. Stimulants may also be prescribed. When these therapies are unsuccessful, counseling may be indicated to help a person adapt to and live with the condition. People with these disorders who have chosen a lifestyle in conformity with their sleeping schedules have no need of treatment, though they may need the diagnosis in order to avoid having to meet for appointments or meetings during their sleep time.
Continuous positive airway pressure
Continuous positive airway pressure
Positive airway pressure is a mode of respiratory ventilation used primarily in the treatment of sleep apnea, for which it was first developed. PAP ventilation is also commonly used for those who are critically ill in hospital with respiratory failure, and in newborn infants...
(CPAP) machines and oral appliances are used nightly at home to manage sleep-related breathing disorders such as apnea. In some cases, upper airway surgery generally performed by an otolaryngologist/head & neck surgeon or occasionally an oral and maxillofacial surgeon
Oral and maxillofacial surgery
Oral and maxillofacial surgery is surgery to correct a wide spectrum of diseases, injuries and defects in the head, neck, face, jaws and the hard and soft tissues of the oral and maxillofacial region. It is an internationally recognized surgical specialty...
is indicated. In mild cases in obese people, weight reduction may be sufficient. The treatments prevent airway collapse, which interrupts breathing during sleep.
Further reading
- American Academy of Sleep Medicine. The International Classification of Sleep Disorders: Diagnostic and Coding Manual. 2nd ed. American Academy of Sleep MedicineAmerican Academy of Sleep MedicineThe American Academy of Sleep Medicine is a United States professional society for the medical subspecialty of sleep medicine. It was established in 1975. The AASM is the only professional society that is dedicated exclusively to the medical subspecialty of sleep medicine...
, 2005.
External links
- The Sleep Centre, Imperial College Healthcare NHS A five-minute video following a patient with obstructive sleep apnoea through diagnosis and treatment
- Directory of AASM-accredited sleep centers in the United States