Narcolepsy is a chronic In medicine, a chronic disease is a disease that is long-lasting or recurrent. The term chronic describes the course of the disease, or its rate of onset and development. A chronic course is distinguished from a recurrent course; recurrent diseases relapse repeatedly, with periods of remission in between. As an adjective, chronic can refer to a sleep disorder A sleep disorder 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. A test commonly ordered for some sleep disorders is the polysomnography, or dyssomnia Patients may complain of difficulty getting to sleep or staying asleep, intermittent wakefulness during the night, early morning awakening, or combinations of any of these. Transient episodes are usually of little significance. Stress, caffeine, physical discomfort, daytime napping, and early bedtimes are common factors, characterized by 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. Sudden involuntary sleep onset, and microsleeps are common complications.[citation needed] EDS is a symptom of one of the two forms of the sleep disorder hypersomnia, the other being prolonged (EDS) in which a person experiences extreme fatigue Fatigue is a state of awareness. It can describe a range of afflictions, varying from a general state of lethargy to a specific work-induced burning sensation within one's muscles. It can be both physical and mental. Physical fatigue is the inability to continue functioning at the level of one's normal abilities. It is ubiquitous in everyday life, and possibly falls asleep at inappropriate times, such as while at work or at school. Narcoleptics usually experience disturbed nocturnal sleep and an abnormal daytime sleep pattern, which is often confused with insomnia Insomnia is a symptom that can accompany several sleep, medical and psychiatric disorders, characterized by persistent difficulty falling asleep and/or difficulty staying asleep. Insomnia is typically followed by functional impairment while awake. When a narcoleptic falls asleep they generally experience the REM Rapid Eye Movement sleep is a normal stage of sleep characterized by the rapid movement of the eyes. REM sleep is classified into two categories: tonic and phasic. It was identified and defined by Nathaniel Kleitman and Eugene Aserinsky in the early 1950s stage of sleep within 10 minutes; whereas most people do not experience REM sleep until after 90 minutes. There is little evidence to suggest that narcoleptics tend to have a shorter life span.

Another problem that some narcoleptics experience is cataplexy Cataplexy is a sudden and transient episode of loss of muscle tone, often triggered by emotions. It is a rare disease , but frequently affects people who have narcolepsy, a disorder whose principal signs are EDS (Excessive Daytime Sleepiness), sleep attacks, sleep paralysis, hypnagogic hallucinations and disturbed night-time sleep. Cataplexy is, a sudden muscular weakness brought on by strong emotions (though many people experience cataplexy without having an emotional trigger^{[citation needed]}). It often manifests as muscular weaknesses ranging from a barely perceptible slackening of the facial muscles to the dropping of the jaw or head, weakness at the knees, or a total collapse. Usually only speech is slurred, vision is impaired (double vision, inability to focus), but hearing and awareness remain normal. In some rare cases, an individual's body becomes paralyzed Paralysis is most often caused by damage to the nervous system, especially the spinal cord. Major causes are stroke, trauma, poliomyelitis, amyotrophic lateral sclerosis , botulism, spina bifida, multiple sclerosis, and Guillain-Barré syndrome. Temporary paralysis occurs during REM sleep, and dysregulation of this system can lead to episodes of and muscles become stiff.

Narcolepsy is a neurological sleep disorder. It is not caused by mental illness or psychological problems. It is most likely affected by a number of genetic abnormalities that affect specific biologic factors in the brain, combined with a set off from environment, such as a virus.^[1]

The term narcolepsy derives from the French word narcolepsie created by the French physician Jean-Baptiste-Édouard Gélineau by combining the Greek Greek , an independent branch of the Indo-European family of languages, is the language of the Greeks. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. In its ancient form, it is the language of classical ancient Greek literature and the New Testament of νάρκη (narkē, "numbness" or "stupor"),^[2][3] and λῆψις (lepsis), "attack" or "seizure".^[4]

Signs and symptoms

The main characteristic of narcolepsy is 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. Sudden involuntary sleep onset, and microsleeps are common complications.[citation needed] EDS is a symptom of one of the two forms of the sleep disorder hypersomnia, the other being prolonged (EDS), even after adequate nighttime sleep. A person with narcolepsy is likely to become drowsy or fall asleep or just be very tired throughout the day, often at inappropriate times and places. Daytime naps may occur with little warning and may be physically irresistible. These naps can occur several times a day. They are typically refreshing, but only for a few hours. Drowsiness may persist for prolonged periods of time. In addition, nighttime sleep may be fragmented with frequent awakenings.

Four of the other classic symptoms of the disorder, often referred to as the "tetrad of narcolepsy," are cataplexy Cataplexy is a sudden and transient episode of loss of muscle tone, often triggered by emotions. It is a rare disease , but frequently affects people who have narcolepsy, a disorder whose principal signs are EDS (Excessive Daytime Sleepiness), sleep attacks, sleep paralysis, hypnagogic hallucinations and disturbed night-time sleep. Cataplexy is, sleep paralysis Sleep paralysis is paralysis associated with sleep that may occur in normal subjects or be associated with narcolepsy, cataplexy, and hypnagogic hallucinations. The pathophysiology of this condition is closely related to the normal hypotonia that occur during REM sleep. When considered to be a disease, isolated sleep paralysis is classified as, hypnagogic hallucinations Hypnagogia , often misspelled hypnogogia, is a term coined by Alfred Maury for the transitional state between wakefulness and sleep, and automatic behavior Automatic behavior, from the Greek automatos or self-acting, is the spontaneous production of often purposeless verbal or motor behavior without conscious self-control or self-censorship. This condition can be observed in a variety of contexts, including schizophrenia, psychogenic fugue, epilepsy , narcolepsy or in response to a traumatic event.^[5] These symptoms may not occur in all patients. Cataplexy is an episodic condition featuring loss of muscle function, ranging from slight weakness (such as limpness at the neck or knees, sagging facial muscles, or inability to speak clearly) to complete body collapse. Episodes may be triggered by sudden emotional reactions such as laughter Laughter is an audible expression or the appearance of happiness, or an inward feeling of joy . It may ensue (as a physiological reaction) from jokes, tickling or other stimuli. It is in most cases a very pleasant sensation, anger Anger is an emotion. The physical effects of anger include increased heart rate, blood pressure, and levels of adrenaline and noradrenaline. Some view anger as part of the fight or flight brain response to the perceived threat of harm. Anger becomes the predominant feeling behaviorally, cognitively, and physiologically when a person makes the, surprise, or fear Fear is an emotional response to a perceived threat. It is a basic survival mechanism occurring in response to a specific stimulus, such as pain or the threat of danger. Some psychologists such as John B. Watson, Robert Plutchik, and Paul Ekman have suggested that fear is one of a small set of basic or innate emotions. This set also includes such, and may last from a few seconds to several minutes. The person remains conscious throughout the episode. In some cases, cataplexy may resemble epileptic seizures.^[6] Sleep paralysis is the temporary inability to talk or move when waking (or less often, when falling asleep). It may last a few seconds to minutes. This is often frightening but is not dangerous. Hypnagogic hallucinations are vivid, often frightening, dreamlike experiences that occur while dozing, falling asleep and/or while awakening.

Automatic behavior means that a person continues to function (talking, putting things away, etc.) during sleep episodes, but awakens with no memory of performing such activities. It is estimated that up to 40 percent of people with narcolepsy experience automatic behavior during sleep episodes. Sleep paralysis and hypnagogic hallucinations also occur in people who do not have narcolepsy, but more frequently in people who are suffering from extreme lack of sleep. Cataplexy is generally considered to be unique to narcolepsy and is analogous to sleep paralysis in that the usually protective paralysis mechanism occurring during sleep is inappropriately activated. The opposite of this situation (failure to activate this protective paralysis) occurs in rapid eye movement behavior disorder Rapid eye movement sleep behavior disorder is a sleep disorder (more specifically a parasomnia) that involves abnormal behavior during the sleep phase with rapid eye movement (REM sleep). It was first described in 1986.

In most cases, the first symptom of narcolepsy to appear is excessive and overwhelming daytime sleepiness. The other symptoms may begin alone or in combination months or years after the onset of the daytime naps. There are wide variations in the development, severity, and order of appearance of cataplexy, sleep paralysis, and hypnagogic hallucinations in individuals. Only about 20 to 25 percent of people with narcolepsy experience all four symptoms. The excessive daytime sleepiness generally persists throughout life, but sleep paralysis and hypnagogic hallucinations may not.

Although these are the common symptoms of narcolepsy, many people with narcolepsy also suffer from insomnia Insomnia is a symptom that can accompany several sleep, medical and psychiatric disorders, characterized by persistent difficulty falling asleep and/or difficulty staying asleep. Insomnia is typically followed by functional impairment while awake for extended periods of time. The symptoms of narcolepsy, especially the excessive daytime sleepiness and cataplexy, often become severe enough to cause serious problems in a person's social, personal, and professional life. Normally, when an individual is awake, brain waves Electroencephalography is the recording of electrical activity along the scalp produced by the firing of neurons within the brain. In clinical contexts, EEG refers to the recording of the brain's spontaneous electrical activity over a short period of time, usually 20–40 minutes, as recorded from multiple electrodes placed on the scalp. In show a regular rhythm. When a person first falls asleep, the brain waves become slower and less regular. This sleep state is called non-rapid eye movement (NREM The sleep stages 1 through 3, previously known as stages 1 through 4, are collectively referred to as non-rapid eye movement, NREM, sleep. Rapid eye movement is not included. There are distinct electroencephalographic and other characteristics seen in each stage. Unlike REM sleep, there is usually little or no eye movement during this stage) sleep. After about an hour and a half of NREM sleep, the brain waves begin to show a more active pattern again. This sleep state, called REM sleep Rapid Eye Movement sleep is a normal stage of sleep characterized by the rapid movement of the eyes. REM sleep is classified into two categories: tonic and phasic. It was identified and defined by Nathaniel Kleitman and Eugene Aserinsky in the early 1950s (rapid eye movement sleep), is when most remembered dreaming A dream is a succession of images, sounds or emotions which the mind experiences during sleep. The content and purpose of dreams are not fully understood, though they have been a topic of speculation and interest throughout recorded history. The scientific study of dreams is known as oneirology occurs. Associated with the EEG-observed waves during REM sleep, muscle atonia is present (called REM atonia Rapid eye movement sleep is a normal stage of sleep characterised by the rapid movement of the eyes. REM sleep is classified into two categories: tonic and phasic. It was identified and defined by Kleitman and Aserinsky in the early 1950s).

In narcolepsy, the order and length of NREM and REM sleep periods are disturbed, with REM sleep occurring at sleep onset instead of after a period of NREM sleep. Thus, narcolepsy is a disorder in which REM sleep appears at an abnormal time. Also, some of the aspects of REM sleep that normally occur only during sleep—lack of muscular control, sleep paralysis, and vivid dreams—occur at other times in people with narcolepsy. For example, the lack of muscular control can occur during wakefulness in a cataplexy episode; it is said that there is intrusion of REM atonia during wakefulness. Sleep paralysis and vivid dreams can occur while falling asleep or waking up. Simply put, the brain does not pass through the normal stages of dozing and deep sleep but goes directly into (and out of) rapid eye movement (REM) sleep.

This has several consequences. Night time sleep does not include as much deep sleep, so the brain tries to "catch up" during the day, hence EDS. People with narcolepsy may visibly fall asleep at unpredicted moments (such motions as head bobbing are common). People with narcolepsy fall quickly into what appears to be very deep sleep, and they wake up suddenly and can be disoriented when they do (dizziness is a common occurrence). They have very vivid dreams, which they often remember in great detail. People with narcolepsy may dream even when they only fall asleep for a few seconds.

Causes

Although the cause of narcolepsy was not determined for many years after its discovery, scientists had discovered conditions that seemed to be associated with an increase in an individual's risk of having the disorder. Specifically, there appeared to be a strong link between narcoleptic individuals and certain genetic conditions. One factor that seemed to predispose an individual to narcolepsy involved an area of Chromosome 6 known as the HLA The human leukocyte antigen system is the name of the major histocompatibility complex (MHC) in humans. The superlocus contains a large number of genes related to immune system function in humans. This group of genes resides on chromosome 6, and encodes cell-surface antigen-presenting proteins and many other genes. The HLA genes are the human complex.^[7] There appeared to be a correlation between narcoleptic individuals and certain variations in HLA genes, although it was not required for the condition to occur. Certain variations in the HLA complex were thought to increase the risk of an auto-immune Autoimmunity is the failure of an organism to recognize its own constituent parts as self, which allows an immune response against its own cells and tissues. Any disease that results from such an aberrant immune response is termed an autoimmune disease. Prominent examples include Coeliac disease, diabetes mellitus type 1 , systemic lupus response to protein Proteins are organic compounds made of amino acids arranged in a linear chain and folded into a globular form. The amino acids in a polymer are joined together by the peptide bonds between the carboxyl and amino groups of adjacent amino acid residues. The sequence of amino acids in a protein is defined by the sequence of a gene, which is encoded-producing neurons in the brain. The protein produced, called hypocretin Orexins, also called hypocretins, are the common names given to a pair of excitatory neuropeptide hormones that were simultaneously discovered by two groups of researchers in rat brains or orexin Orexins, also called hypocretins, are the common names given to a pair of excitatory neuropeptide hormones that were simultaneously discovered by two groups of researchers in rat brains, is responsible for controlling appetite and sleep patterns.^[8] Individuals with narcolepsy often have reduced numbers of these protein-producing neurons in their brains.^[8] In 2009 the autoimmune hypothesis was supported by research carried out at Stanford University School of Medicine.^[9][10]

The neural control of normal sleep states and the relationship to narcolepsy are only partially understood. In humans, narcoleptic sleep is characterized by a tendency to go abruptly from a waking state to REM sleep with little or no intervening non-REM sleep. The changes in the motor and proprioceptive systems during REM sleep have been studied in both human and animal models. During normal REM sleep, spinal and brainstem alpha motor neuron Alpha motor neurons are large lower motor neurons of the brainstem and spinal cord. They innervate extrafusal muscle fibers of skeletal muscle and are directly responsible for initiating their contraction. Alpha motor neurons are distinct from gamma motor neurons, which innervate intrafusal muscle fibers of muscle spindles depolarization In biology, depolarization is a change in a cell's membrane potential, making it more positive, or less negative. In neurons and some other cells, a large enough depolarization may result in an action potential. Hyperpolarization is the opposite of depolarization, and inhibits the rise of an action potential produces almost complete atonia In medicine, atony refers to a muscle that has lost its strength. It is frequently associated with the conditions Atonic seizure, atonic colon, uterine atony, gastrointestinal atony (occurs postoperatively) and choreatic atonia of skeletal muscles Skeletal muscle is a form of striated muscle tissue existing under control of the somatic nervous system. It is one of three major muscle types, the others being cardiac and smooth muscle. As its name suggests, most skeletal muscle is attached to bones by bundles of collagen fibers known as tendons via an inhibitory descending reticulospinal pathway. Acetylcholine The chemical compound acetylcholine is a neurotransmitter in both the peripheral nervous system (PNS) and central nervous system (CNS) in many organisms including humans. Acetylcholine is one of many neurotransmitters in the autonomic nervous system (ANS) and the only neurotransmitter used in the motor division of the somatic nervous system. ( may be one of the neurotransmitters Neurotransmitters are endogenous chemicals which transmit signals from a neuron to a target cell across the synapse. Neurotransmitters are packaged into synaptic vesicles that cluster beneath the membrane on the presynaptic side of a synapse, and are released into the synaptic cleft, where they bind to receptors in the membrane on the postsynaptic involved in this pathway. In narcolepsy, the reflex inhibition of the motor system seen in cataplexy is believed to be identical to that seen in normal REM sleep.^{[citation needed]}

In 2004 researchers in Australia induced narcolepsy-like symptoms in mice by injecting them with antibodies from narcoleptic humans. The research has been published in the Lancet providing strong evidence suggesting that some cases of narcolepsy might be caused by autoimmune disease.^[11] Narcolepsy is strongly associated with HLA-DQB1 Major histocompatibility complex, class II, DQ beta 1, also known as HLA-DQB1, is a human gene and also denotes the genetic locus which contains this gene. The protein encoded by this gene is one of two proteins that are required to form the DQ heterodimer, a cell surface receptor essential to the function of the immune system*0602 genotype The genotype is the genetic constitution of a cell, an organism, or an individual usually with reference to a specific character under consideration. For instance, the human albino gene has two recessive alleles, recessive a and recessive a. It is a generally accepted theory that inherited genotype, transmitted epigenetic factors, and non-.^[12] There is also an association with HLA-DR2 and HLA-DQ1. This may represent linkage disequilibrium In population genetics, linkage disequilibrium is the non-random association of alleles at two or more loci, not necessarily on the same chromosome. It is not the same as linkage, which describes the association of two or more loci on a chromosome with limited recombination between them. Linkage disequilibrium describes a situation in which some. Despite the experimental evidence in human narcolepsy that there may be an inherited basis for at least some forms of narcolepsy, the mode of inheritance remains unknown. Some cases are associated with genetic diseases such as Niemann-Pick disease Niemann–Pick disease refers to a group of fatal inherited metabolic disorders that are included in the larger family of lysosomal storage diseases (LSDs).:536^[13] or Prader-Willi syndrome Prader-Willi syndrome is a very rare genetic disorder in which seven genes (or some subset thereof) on chromosome 15 (q 11-13) are deleted or unexpressed (chromosome 15q partial deletion) on the paternal chromosome. It was first described in 1956 by Andrea Prader, Heinrich Willi, Alexis Labhart, Andrew Ziegler, and Guido Fanconi of Switzerland.^[14]

Diagnosis

Diagnosis is relatively easy when all the symptoms of narcolepsy are present, but if the sleep attacks are isolated and cataplexy is mild or absent, diagnosis is more difficult. It is also possible for cataplexy to occur in isolation. Two tests that are commonly used in diagnosing narcolepsy are the polysomnogram 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. The name is derived from Greek and Latin roots: the Greek πολύς (polus for "many, much", indicating many channels), the and the multiple sleep latency test The Multiple Sleep Latency Test is a sleep disorder diagnostic tool. It is used to measure the time it takes from the start of a daytime nap period to the first signs of sleep, called sleep latency. The test is based on the idea that the sleepier people are, the faster they will fall asleep (MSLT). These tests are usually performed by a sleep specialist 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. The polysomnogram involves continuous recording of sleep brain waves and a number of nerve and muscle functions during nighttime sleep. When tested, people with narcolepsy fall asleep rapidly, enter REM sleep early, and may awaken often during the night. The polysomnogram also helps to detect other possible sleep disorders that could cause daytime sleepiness.

For the multiple sleep latency test, a person is given a chance to sleep every 2 hours during normal wake times. Observations are made of the time taken to reach various stages of sleep (sleep onset latency). This test measures the degree of daytime sleepiness and also detects how soon REM sleep begins. Again, people with narcolepsy fall asleep rapidly and enter REM sleep early.

Treatment

Treatment is tailored to the individual, based on symptoms and therapeutic response. The time required to achieve optimal control of symptoms is highly variable, and may take several months or longer. Medication adjustments are also frequently necessary, and complete control of symptoms is seldom possible. While oral medications are the mainstay of formal narcolepsy treatment, lifestyle changes are also important.

The main treatment of excessive daytime sleepiness in narcolepsy is with central nervous system The central nervous system is the part of the nervous system that coordinates the activity of all parts of the bodies of bilaterian animals—that is, all multicellular animals except sponges and radially symmetric animals such as jellyfish. It contains the majority of the nervous system and consists of the brain and the spinal cord, as well as stimulant drugs such as methylphenidate Methylphenidate is a psychostimulant drug approved for treatment of attention-deficit hyperactivity disorder, Postural Orthostatic Tachycardia Syndrome, and narcolepsy. It may also be prescribed for off-label use in treatment-resistant cases of lethargy, depression, neural insult, obesity, and rarely other psychiatric disorders such as Obsessive-, racemic In chemistry, a racemic mixture, or racemate, is one that has equal amounts of left- and right-handed enantiomers of a chiral molecule. The first known racemic mixture was "racemic acid," which Louis Pasteur found to be a mixture of the two enantiomeric isomers of tartaric acid - amphetamine Amphetamine or amfetamine (INN) is a psychostimulant drug that is known to produce increased wakefulness and focus in association with decreased fatigue and appetite. Amphetamine is chemically related to methamphetamine and lisdexamfetamine, a class of potent drugs that act by increasing levels of dopamine and norepinephrine in the brain, inducing, dextroamphetamine Dextroamphetamine is a psychostimulant drug which is known to produce increased wakefulness and focus in association with decreased fatigue and decreased appetite. Drugs with similar psychoactive properties can be referred to or described as "amphetamine analogues", "amphetamine-like", or having "amphetaminergic", and methamphetamine Methamphetamine , also known as metamfetamine (INN), dextromethamphetamine, methylamphetamine, N-methylamphetamine, desoxyephedrine, and colloquially as meth (not to be confused with methadone, sometimes referred to as "meth" by opioid users) or crystal meth, is a psychoactive stimulant (psychostimulant or psychoanaleptic) drug. It, or modafinil (Provigil), a new stimulant with a different pharmacologic mechanism, and more recently, armodafinil (Nuvigil). In Fall 2007 an alert for severe adverse skin reactions to modafinil was issued by the FDA.^[15] Other medications used are codeine^[16] and selegiline.^[17] Another drug that is used is atomoxetine^[18] (Strattera), a non-stimulant and norepinephrine reuptake inhibitor (NRI), that has little or no abuse potential.^[19] In many cases, planned regular short naps can reduce the need for pharmacological treatment of the EDS to a low or non-existent level.

Cataplexy and other REM-sleep symptoms are frequently treated with tricyclic antidepressants such as clomipramine, imipramine, or protriptyline, as well as other drugs that suppress REM sleep. Venlafaxine (branded as Effexor XR by Wyeth Pharmaceuticals), an antidepressant which blocks the reuptake of serotonin and norepinephrine, has shown usefulness in managing symptoms of cataplexy,^[20] however, it has notable side-effects including sleep disruption.

Gamma-hydroxybutyrate (GHB), more commonly known on the pharmaceutical market as Sodium Oxybate, or Xyrem (branded by Jazz Pharmaceuticals), is the only medication specifically indicated and approved for narcolepsy and cataplexy. Gamma-hydroxybutyrate has been shown to reduce symptoms of EDS associated with narcolepsy. While the exact mechanism of action is unknown, GHB is thought to improve the quality of nocturnal sleep by increasing the prevalence of slow wave (delta) sleep (as this is the time when the brain is least active and therefore most at rest and able to rebuild and repair itself physiologically). GHB appears to help sufferers much more effectively than the hypnotic class of medications typically used for insomnia (hypnotics tend to obstruct delta wave sleep), so it can be vital to be properly diagnosed as narcoleptic rather than insomniac. GHB was previously available on the open market as a dietary supplement but was reclassified a controlled substance in the United States due to pressure associated with the abuse of the chemical (it is infamously known as the date rape drug). It can currently only be legally acquired through prescription, after very specific diagnoses (typically for narcolepsy itself). Many healthcare providers, such as Welfare prescription plans in the US, are unwilling to pay for the expensive drug and will instead present patients with stimulants.

Using stimulants to mask daytime sleepiness does not address the actual cause of the problem. Stimulants may provide some assistance with daytime activity, but the underlying cause will remain and potentially worsen over time due to the stimulant itself becoming an obstruction to delta wave sleep periods. Lifestyle changes involving reduced stress, more exercise (especially for overweight persons experiencing narcolepsy caused by sleep apnea and snoring) and less stimulant intake (such as coffee and nicotine) are likely to be ideal forms of assistive treatment. Some people with narcolepsy have a nocturnal body clock and are helped by selecting an occupation that properly coincides with their body's natural sleep cycle (such as sleeping in the day and working at night). This allows sufferers to avoid the need to force themselves into the more common 9 to 5 schedule that their body is unable to maintain, and avoids the need to take stimulants to remain active during the times when their bodies are inclined to rest.

In addition to drug therapy, an important part of treatment is scheduling short naps (10 to 15 minutes) two to three times per day to help control excessive daytime sleepiness and help the person stay as alert as possible. Daytime naps are not a replacement for nighttime sleep, especially if a person's body is natively inclined towards a nocturnal life cycle. Ongoing communication between the health care provider, patient, and the patient's family members is important for optimal management of narcolepsy.

Finally, a recent study reported that transplantation of hypocretin neurons into the pontine reticular formation in rats is feasible, indicating the development of alternative therapeutic strategies in addition to pharmacological interventions.^[21]

Epidemiology

It is estimated that as many as 3 million people worldwide are affected by narcolepsy. In the United States, it is estimated that this condition afflicts as many as 200,000 Americans,^[22] but fewer than 50,000 are diagnosed. It is as widespread as Parkinson's disease or multiple sclerosis and more prevalent than cystic fibrosis, but it is less well known. Narcolepsy is often mistaken for depression, epilepsy, or the side effects of medications. It can also be mistaken for poor sleeping habits, recreational drug use, or laziness. Narcolepsy can occur in both men and women at any age, although its symptoms are usually first noticed in teenagers or young adults. There is strong evidence that narcolepsy may run in families; 8 to 12 percent of people with narcolepsy have a close relative with this neurologic disorder.^{[citation needed]}

Narcolepsy has its typical onset in adolescence and young adulthood. There is an average 15-year delay between onset and correct diagnosis which may contribute substantially to the disabling features of the disorder. Cognitive, educational, occupational, and psychosocial problems associated with the excessive daytime sleepiness of narcolepsy have been documented. For these to occur in the crucial teen years when education, development of self-image, and development of occupational choice are taking place is especially damaging. While cognitive impairment does occur, it may only be a reflection of the excessive daytime somnolence.

The prevalence of narcolepsy is about 1 per 2,000 persons.^[22] It is a reason for patient visits to sleep disorder centers, and with its onset in adolescence, it is also a major cause of learning difficulty and absenteeism from school. Normal teenagers often already experience excessive daytime sleepiness because of a maturational increase in physiological sleep tendency accentuated by multiple educational and social pressures; this may be disabling with the addition of narcolepsy symptoms in susceptible teenagers. In clinical practice, the differentiation between narcolepsy and other conditions characterized by excessive somnolence may be difficult. Treatment options are currently limited. There is a paucity in the literature of controlled double-blind studies of possible effective drugs or other forms of therapy. Mechanisms of action of some of the few available therapeutic agents have been explored but detailed studies of mechanisms of action are needed before new classes of therapeutic agents can be developed. Narcolepsy is an underdiagnosed condition in the general population. This is partly because its severity varies from obvious to barely noticeable. Some people with narcolepsy do not suffer from loss of muscle control. Others may only feel sleepy in the evenings.

Famous people with narcolepsy

• Sergio Kindle, football player^[23]
• Harriet Tubman, abolitionist (1830–1913)
• Aaron Flahavan, footballer (1975–2001)
• Jimmy Kimmel, TV host^[24]
• Hank Aaron, baseball player^[25]

Society and culture

Depictions of the disorder in fiction and pop culture can range greatly in the accuracy of how they depict the symptoms. Narcolepsy is often depicted in an exaggerated fashion in comedy films or TV shows. In the movie Rat Race, one of the main characters (Enrico Pollini, played by Rowan Atkinson) has narcolepsy and is very eccentric. This portrayal has been criticized for its inaccuracy and insensitivity to the disorder.^{[citation needed]}

The Little Sleep, a detective novel by Paul Tremblay, portrayed the main character, Mark G. as having narcolepsy. In relating Mark's thoughts and experiences the author captures many esoteric nuances of the experience of narcolepsy. As narcolepsy is an "invisible" disease, most people don't really understand how pervasive the symptoms are—how the symptoms alter your perception of events, and may at times blur the boundaries between what is experienced when awake, and what was experienced in sleep. The character deals with daily, even hourly frustrations due to the general cognitive fog, not being able to trust his own memory and even not being able to drive. Many of these situations are presented as humorous, but the reader is always laughing with Mark, rather than at him. Mark shares the frustration felt by many with narcolepsy, that his disease is not taken seriously and that he is "the punch line in a joke".

In Gus Van Sant's independent, art house drama My Own Private Idaho (1991) the lead character, Mike Waters (played by River Phoenix) has narcolepsy. In the opening scene, a dictionary definition of the condition is presented on screen. Phoenix's characters narcolepic episodes are used as a transition tool; transporting the characters from place to place throughout the course of the film and are interpreted with dream-like sequences of time lapsed skies, barns falling from the air and salmon swimming upstream. The characters seizures are brought on by stressful situations, which come about quite frequently as he is a male hustler by profession. Although the characters narcolepic blackouts are used to link the film together; Phoenix presents the seizures true to life as opposed to adding a comedy element and narcolepsy is portrayed as just another facet of the character- not the character by definition.

See also

• Cataplexy
• Dyssomnia
• Orexin
• Microsleep
• List of people with narcolepsy
• Sleep medicine
• Sleep Inertia

References

1. ^ Entry Narcolepsy-Causes in the University of Maryland Medical Center Harvey Simon, Associate Prof of Medicine, Harvard University & David Zieve, Medical Director of A.D.A.M, Inc.
2. ^ http://en.wiktionary.org/wiki/νάρκη
3. ^ Entry Narcolepsy. in the Online Etymology Dictionary. Douglas Harper, Historian. 18 Sep 2007.
4. ^ http://en.wiktionary.org/wiki/-lepsy
5. ^ Kandel, Eric R.; James H. Schwartz, Thomas M. Jessell. Principles of Neural Science (4th ed.). McGraw-Hill. p. 949. ISBN 0-8385-7701-6.
6. ^ http://www.taumed.com/content/adam/browse.jsp?pid=10&cid=000098
7. ^ Klein J, Sato A (September 2000). "The HLA system. Second of two parts". N. Engl. J. Med. 343 (11): 782–6. doi:10.1056/NEJM200009143431106. PMID 10984567.
8. ^ ^{a b} Mignot, E (2001). "A commentary on the neurobiology of the hypocretin/orexin system". Neuropsychopharmacology 25 (5 Suppl): S5-13. doi:10.1016/S0893-133X(01)00316-5. PMID 11682267.
9. ^ Hallmayer J, Faraco J, Lin L, et al. (June 2009). "Narcolepsy is strongly associated with the T-cell receptor alpha locus". Nat. Genet. 41 (6): 708–11. doi:10.1038/ng.372. PMID 19412176.
10. ^ "Narcolepsy is an autoimmune disorder, Stanford researcher says". EurekAlert. American Association for the Advancement of Science. 2009-05-03. http://www.eurekalert.org/pub_releases/2009-05/sumc-nia042809.php. Retrieved 2009-05-31.
11. ^ "BBC News article". 2004-12-13. http://news.bbc.co.uk/1/hi/health/4081225.stm. Retrieved 2010-01-06.
12. ^ Maret, S; Tafti M (November 2005). "Genetics of narcolepsy and other major sleep disorders" (PDF). Swiss Medical Weekly (EMH Swiss Medical Publishers Ltd.) 135 (45-46): 662–5. PMID 16453205. http://www.smw.ch/docs/pdf200x/2005/45/smw-11162.pdf. Retrieved 2008-03-07.
13. ^ Vankova J, Stepanova I, Jech R, et al. (June 2003). "Sleep disturbances and hypocretin deficiency in Niemann-Pick disease type C". Sleep 26 (4): 427–30. PMID 12841368.
14. ^ Manni R, Politini L, Nobili L, et al. (May 2001). "Hypersomnia in the Prader Willi syndrome: clinical-electrophysiological features and underlying factors". Clin Neurophysiol 112 (5): 800–5. doi:10.1016/S1388-2457(01)00483-7. PMID 11336895. http://linkinghub.elsevier.com/retrieve/pii/S1388-2457(01)00483-7.
15. ^ Modafinil (marketed as Provigil): Serious Skin Reactions; FDA Drug Safety Newsletter
16. ^ Fry, JM; Pressman, MR; Diphillipo, MA; Forst-Paulus, M (1986). "Treatment of narcolepsy with codeine". Sleep 9 (1 Pt 2): 269–74. PMID 3518019.
17. ^ Mayer, G; Ewert Meier, K; Hephata, K (1995). "Selegeline hydrochloride treatment in narcolepsy. A double-blind, placebo-controlled study". Clin Neuropharmacol 18 (4): 306–19. doi:10.1097/00002826-199508000-00002. PMID 8665543.
18. ^ "Stanford Center for Narcolepsy article". http://med.stanford.edu/school/Psychiatry/narcolepsy/medications.html.
19. ^ "Curtin University of Technology Article" (PDF). http://adhdproject.curtin.edu.au/forms/STRATTERA%20PI%20(marketed%20products).pdf.
20. ^ Caputo, F; Zoli, G; Provini, Federica; Albani, Fiorenzo; Riva, Roberto (March 2007). "Treatment of narcolepsy with cataplexy". Lancet 369 (9567): 1080–1081. doi:10.1016/S0140-6736(07)60523-6. PMID 17398302.
21. ^ Arias-Carrión O, Murillo-Rodriguez E, Xu M, Blanco-Centurion C, Drucker-Colín R, Shiromani PJ (December 2004). "Transplantation of hypocretin neurons into the pontine reticular formation: preliminary results". Sleep 27 (8): 1465–70. PMID 15683135.
22. ^ ^{a b} "Who Is At Risk for Narcolepsy?". http://www.nhlbi.nih.gov/health/dci/Diseases/nar/nar_who.html.
23. ^ Texas coach Mack Brown says Narcolepsy may have caused Sergio Kindle's fall down stairs[1]
24. ^ Carter, Bill (November 3, 2003). "In The Land Of The Insomniac The Narcoleptic Wants To Be King". New York Times. http://www.nytimes.com/2002/11/03/magazine/in-the-land-of-the-insomniac-the-narcoleptic-wants-to-be-king.html. Retrieved 2009-12-11.
25. ^ Entry [2]Narcolepsy

Sources

• Mitler, M.M.; Hajdukovic, R (June 1991). "Relative Efficacy of Drugs for the treatment of Sleepiness in Narcolepsy". Sleep 14 (3): 218. PMID 1680245.
• Chabas, D; Taheri, S; Renier, C; Mignot, E (October 2003). "The Genetics of Narcolepsy". Annual Review of Genomics & Human Genetics 4: 459. doi:10.1146/annurev.genom.4.070802.110432. PMID 14527309.
• Smith AJ, Jackson MW, Neufing P, McEvoy RD, Gordon TP (2004). "A functional autoantibody in narcolepsy". Lancet 364 (9451): 2122–4. doi:10.1016/S0140-6736(04)17553-3. PMID 15589310. http://linkinghub.elsevier.com/retrieve/pii/S0140673604175533.

External links

• Stanford University: Center for Narcolepsy
• Narcolepsy Network Organization
• Narcolepsy Fact Sheet: National Institute of Neurological Disorders and Stroke
• http://www.narcolepsy.org.uk/index_html
• Read about Narcolepsy in the Sleeptionary
• What is Narcolepsy
• Narcolepsy: Symptoms, Causes, Diagnosis and Treatment
• Narcolepsy & Cataplexy videos and case study
• Transplantation of hypocretin neurons into the pontine reticular formation: preliminary results
• Living With Narcolepsy
• Narcolepsy Linked to Immune System Problem
• Video explaining that narcolepsy is an autoimmune disorder.

Categories: Sleep | Sleep disorders

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• Narcolepsy: Encyclopedia
• Health: Conditions and Diseases: Sleep Disorders: Narcolepsy: Directory

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