Related Research Articles
Sleep is a state of reduced mental and physical activity in which consciousness is altered and sensory activity is inhibited to a certain extent. During sleep, there is a decrease in muscle activity, and interactions with the surrounding environment. While sleep differs from wakefulness in terms of the ability to react to stimuli, it still involves active brain patterns, making it more reactive than a coma or disorders of consciousness.
A sleep disorder, or somnipathy, is a medical disorder of an individual's sleep patterns. Some sleep disorders are severe enough to interfere with normal physical, mental, social and emotional functioning. Polysomnography and actigraphy are tests commonly ordered for diagnosing sleep disorders.
Jet lag is a physiological condition that results from alterations to the body's circadian rhythms caused by rapid long-distance trans-meridian travel. For example, someone flying from New York to London, i.e. from west to east, feels as if the time were five hours earlier than local time, and someone travelling from London to New York, i.e. from east to west, feels as if the time were five hours later than local time. The phase shift when traveling from east to west is referred to as phase-delay of the circadian circle, whereas going west to east is phase-advance of the circadian circle. Most travelers find that it is harder to timezone adjust when traveling to the east. Jet lag was previously classified as one of the circadian rhythm sleep disorders.
African trypanosomiasis, also known as African sleeping sickness or simply sleeping sickness, is an insect-borne parasitic infection of humans and other animals. It is caused by the species Trypanosoma brucei. Humans are infected by two types, Trypanosoma brucei gambiense (TbG) and Trypanosoma brucei rhodesiense (TbR). TbG causes over 92% of reported cases. Both are usually transmitted by the bite of an infected tsetse fly and are most common in rural areas.
Delayed sleep phase disorder (DSPD), more often known as delayed sleep phase syndrome and also as delayed sleep–wake phase disorder, is the delaying of a person's circadian rhythm compared to those of societal norms. The disorder affects the timing of biological rhythms including sleep, peak period of alertness, core body temperature, and hormonal cycles.
Advanced Sleep Phase Disorder (ASPD), also known as the advanced sleep-phase type (ASPT) of circadian rhythm sleep disorder, is a condition that is characterized by a recurrent pattern of early evening sleepiness and very early morning awakening. This sleep phase advancement can interfere with daily social and work schedules, and results in shortened sleep duration and excessive daytime sleepiness. The timing of sleep and melatonin levels are regulated by the body's central circadian clock, which is located in the suprachiasmatic nucleus in the hypothalamus.
Encephalopathy means any disorder or disease of the brain, especially chronic degenerative conditions. In modern usage, encephalopathy does not refer to a single disease, but rather to a syndrome of overall brain dysfunction; this syndrome has many possible organic and inorganic causes.
Somnolence is a state of strong desire for sleep, or sleeping for unusually long periods. It has distinct meanings and causes. It can refer to the usual state preceding falling asleep, the condition of being in a drowsy state due to circadian rhythm disorders, or a symptom of other health problems. It can be accompanied by lethargy, weakness and lack of mental agility.
Hepatic encephalopathy (HE) is an altered level of consciousness as a result of liver failure. Its onset may be gradual or sudden. Other symptoms may include movement problems, changes in mood, or changes in personality. In the advanced stages it can result in a coma.
Non-24-hour sleep–wake disorder is one of several chronic circadian rhythm sleep disorders (CRSDs). It is defined as a "chronic steady pattern comprising [...] daily delays in sleep onset and wake times in an individual living in a society". Symptoms result when the non-entrained (free-running) endogenous circadian rhythm drifts out of alignment with the light–dark cycle in nature. Although this sleep disorder is more common in blind people, affecting up to 70% of the totally blind, it can also affect sighted people. Non-24 may also be comorbid with bipolar disorder, depression, and traumatic brain injury. The American Academy of Sleep Medicine (AASM) has provided CRSD guidelines since 2007 with the latest update released in 2015.
Circadian rhythm sleep disorders (CRSD), also known as circadian rhythm sleep-wake disorders (CRSWD), are a family of sleep disorders which affect the timing of sleep. CRSDs arise from a persistent pattern of sleep/wake disturbances that can be caused either by dysfunction in one's biological clock system, or by misalignment between one's endogenous oscillator and externally imposed cues. As a result of this mismatch, those affected by circadian rhythm sleep disorders have a tendency to fall asleep at unconventional time points in the day. These occurrences often lead to recurring instances of disturbed rest, where individuals affected by the disorder are unable to go to sleep and awaken at "normal" times for work, school, and other social obligations. Delayed sleep phase disorder, advanced sleep phase disorder, non-24-hour sleep–wake disorder and irregular sleep–wake rhythm disorder represents the four main types of CRSD.
Shift work sleep disorder (SWSD) is a circadian rhythm sleep disorder characterized by insomnia, excessive sleepiness, or both affecting people whose work hours overlap with the typical sleep period. Insomnia can be the difficulty to fall asleep or to wake up before the individual has slept enough. About 20% of the working population participates in shift work. SWSD commonly goes undiagnosed, so it's estimated that 10–40% of shift workers have SWSD. The excessive sleepiness appears when the individual has to be productive, awake and alert. Both symptoms are predominant in SWSD. There are numerous shift work schedules, and they may be permanent, intermittent, or rotating; consequently, the manifestations of SWSD are quite variable. Most people with different schedules than the ordinary one might have these symptoms but the difference is that SWSD is continual, long-term, and starts to interfere with the individual's life.
The International Classification of Sleep Disorders (ICSD) is "a primary diagnostic, epidemiological and coding resource for clinicians and researchers in the field of sleep and sleep medicine". The ICSD was produced by the American Academy of Sleep Medicine (AASM) in association with the European Sleep Research Society, the Japanese Society of Sleep Research, and the Latin American Sleep Society. The classification was developed as a revision and update of the Diagnostic Classification of Sleep and Arousal Disorders (DCSAD) that was produced by both the Association of Sleep Disorders Centers (ASDC) and the Association for the Psychophysiological Study of Sleep and was published in the journal Sleep in 1979. A second edition, called ICSD-2, was published by the AASM in 2005. The third edition, ICSD-3, was released by the AASM in 2014. A text revision of the third edition (ICSD-3-TR) was published in 2023 by the AASM.
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 of, 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 physicians who treat patients may be the same people.
Sleep deprivation, also known as sleep insufficiency or sleeplessness, is the condition of not having adequate duration and/or quality of sleep to support decent alertness, performance, and health. It can be either chronic or acute and may vary widely in severity.
Sundowning, or sundown syndrome, is a neurological phenomenon associated with increased confusion and restlessness in people with delirium or some form of dementia. It is most commonly associated with Alzheimer's disease but also found in those with other forms of dementia. The term "sundowning" was coined by nurse Lois K. Evans in 1987 due to the timing of the person's increased confusion beginning in the late afternoon and early evening. For people with sundown syndrome, a multitude of behavioral problems begin to occur and are associated with long term adverse outcomes. Sundowning seems to occur more frequently during the middle stages of Alzheimer's disease and mixed dementia and seems to subside with the progression of the person's dementia. People are generally able to understand that this behavioral pattern is abnormal. Research shows that 20–45% of people with Alzheimer's will experience some variation of sundowning confusion. However, despite lack of an official diagnosis of sundown syndrome in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), there is currently a wide range of reported prevalence.
Irregular sleep–wake rhythm disorder (ISWRD) is a rare form of circadian rhythm sleep disorder. It is characterized by numerous naps throughout the 24-hour period, no main nighttime sleep episode, and irregularity from day to day. Affected individuals have no pattern of when they are awake or asleep, may have poor quality sleep, and often may be very sleepy while they are awake. The total time asleep per 24 hours is normal for the person's age. The disorder is serious—an invisible disability. It can create social, familial, and work problems, making it hard for a person to maintain relationships and responsibilities, and may make a person home-bound and isolated.
Classification of sleep disorders comprises systems for classifying medical disorders associated with sleep. Systems have changed, increasingly using technological discoveries to advance the understanding of sleep and recognition of sleep disorders.
Sleep is known to play an important role in the etiology and maintenance of bipolar disorder. Patients with bipolar disorder often have a less stable and more variable circadian activity. Circadian activity disruption can be apparent even if the person concerned is not currently ill.
Behavioral sleep medicine (BSM) is a field within sleep medicine that encompasses scientific inquiry and clinical treatment of sleep-related disorders, with a focus on the psychological, physiological, behavioral, cognitive, social, and cultural factors that affect sleep, as well as the impact of sleep on those factors. The clinical practice of BSM is an evidence-based behavioral health discipline that uses primarily non-pharmacological treatments. BSM interventions are typically problem-focused and oriented towards specific sleep complaints, but can be integrated with other medical or mental health treatments. The primary techniques used in BSM interventions involve education and systematic changes to the behaviors, thoughts, and environmental factors that initiate and maintain sleep-related difficulties.
References
- ↑ Morgan, M. Y. (2010). Alteration in Circadian Rhythms in patients with liver disease. London: University College.
- ↑ Bosoi, Cristina R.; Rose, Christopher F. (March 2009). "Identifying the direct effects of ammonia on the brain". Metabolic Brain Disease. 24 (1): 95–102. doi:10.1007/s11011-008-9112-7. hdl: 1866/9593 . ISSN 0885-7490. PMID 19104924. S2CID 3330087.
- ↑ Mandiga, Pujyitha; Foris, Lisa A.; Kassim, Gassan; Bollu, Pradeep C. (2020), "Hepatic Encephalopathy", StatPearls, StatPearls Publishing, PMID 28613619 , retrieved 2020-05-17
- ↑ "CDC - African Trypanosomiasis - Disease". www.cdc.gov. 2020-04-28. Retrieved 2020-08-11.
- ↑ Maxfield, Luke; Bermudez, Rene (2020), "Trypanosomiasis (Trypansomiasis)", StatPearls, Treasure Island (FL): StatPearls Publishing, PMID 30571034 , retrieved 2020-08-11