Histamine plays a role in wakefulness in the brain. An allergic reaction over produces histamine causing wakefulness and inhibiting sleep[37] Sleep problems are common in people with allergic rhinitis. A study from the N.I.H. found that sleep is dramatically impaired by allergic symptoms and that the degree of impairment is related to the severity of those symptoms [2]s[38] Treatment of allergies has also been shown to help sleep apnea.[39]

On the other hand, it is during sleep that beta-amyloid residues are degraded to prevent plaque formation.[29][30][32] It is the glymphatic system that is responsible for this and this phenomenon is called glymphatic clearance.[29][30][32] Thus, during wakefulness, the AB burden is greater because the metabolic activity and oxidative stress are higher and there is no degradation of the protein by the glymphatic clearance whereas during sleep, the burden will be smaller as there will be less metabolic activity and oxidative stress in addition to the glymphatic clearance that occurs at this time.[30][29]
The neurodegenerative conditions are commonly related to brain structures impairment, which might disrupt the states of sleep and wakefulness, circadian rhythm, motor or non motor functioning.[22][24] On the other hand, sleep disturbances are also frequently related to worsening patient's cognitive functioning, emotional state and quality of life.[24][27][28] Furthermore, these abnormal behavioural symptoms negatively contribute to overwhelming their relatives and caregivers.[24][27][28] Therefore, a deeper understanding of the relationship between sleep disorders and neurodegenerative diseases seems to be extremely important, mainly considering the limited research related to it and the increasing expectancy of life.[22][28]
Sort of a milder cousin of sleep apnea, UARS occurs when some type of resistance slows or blocks air in the nasal passages. The most common causes are mild nasal congestion or a tongue position during sleep that blocks breathing. Because the resistance makes it harder work simply to breathe, your body is half-waking up over and over again during the night, so you don't feel refreshed in the morning.
Restless legs syndrome (RLS) is a sleep disorder that causes an almost irresistible urge to move your legs (or arms) at night. The urge to move occurs when you’re resting or lying down and is usually due to uncomfortable, tingly, aching, or creeping sensations. There are plenty of ways to help manage and relieve symptoms, though, including self-help remedies you can use at home.
Narcolepsy is a brain disorder that causes excessive daytime sleepiness. There is sometimes a genetic component, but most patients have no family history of the problem. Though dramatic and uncontrolled "sleep attacks" have been the best-known feature of narcolepsy, in reality many patients do not have sleep attacks. Instead, they experience constant sleepiness during the day.
A study that was resulted from a collaboration between Massachusetts General Hospital and Merck describes the development of an algorithm to identify patients will sleep disorders using electronic medical records. The algorithm that incorporated a combination of structured and unstructured variables identified more than 36,000 individuals with physician-documented insomnia.[62]
A review of the evidence in 2012 concluded that current research is not rigorous enough to make recommendations around the use of acupuncture for insomnia.[40] The pooled results of two trials on acupuncture showed a moderate likelihood that there may be some improvement to sleep quality for individuals with a diagnosis insomnia.[40]:15 This form of treatment for sleep disorders is generally studied in adults, rather than children. Further research would be needed to study the effects of acupuncture on sleep disorders in children.
Narcolepsy is a brain disorder that causes excessive daytime sleepiness. There is sometimes a genetic component, but most patients have no family history of the problem. Though dramatic and uncontrolled "sleep attacks" have been the best-known feature of narcolepsy, in reality many patients do not have sleep attacks. Instead, they experience constant sleepiness during the day.
With over 80 listed sleep disorders, and more that are being researched, it's important for patients suffering from the various types of sleep disorders to seek medical treatment. If you believe that your sleep problems may be caused by a disorder, there are many things you can do to solve your sleep issues from DIY tips and tricks such as practicing better sleep hygiene, to contacting a sleep clinic to schedule an inlab sleep study, or an at home sleep test for certain pre-screened disorders such as obstructive sleep apnea.
Combining results from 17 studies on insomnia in China, a pooled prevalence of 15.0% is reported for the country.[60] This is considerably lower than a series of Western countries (50.5% in Poland, 37.2% in France and Italy, 27.1% in USA).[60] However, the result is consistent among other East Asian countries. Men and women residing in China experience insomnia at similar rates.[60] A separate meta-analysis focusing on this sleeping disorder in the elderly mentions that those with more than one physical or psychiatric malady experience it at a 60% higher rate than those with one condition or less. It also notes a higher prevalence of insomnia in women over the age of 50 than their male counterparts.[61]

What to do: See your dentist for an exam. Bite problems are often a cause of bruxism, and it's a good idea to check for damage to your teeth. It's likely she'll suggest lifestyle changes, such as cutting out alcohol before bed. If you chew gum, stop -- the habitual chewing action can make it more likely you'll grind your teeth at night. Wearing a dental guard or splint at night is usually the next step for bruxism. Your dentist will fit you with a device that prevents your jaw from clenching. Other treatments include Botox injections to the jaw muscle, and a biofeedback device called Grindcare.
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