^ Tranah, Gregory J.; Blackwell, Terri; Stone, Katie L.; Ancoli‐Israel, Sonia; Paudel, Misti L.; Ensrud, Kristine E.; Cauley, Jane A.; Redline, Susan; Hillier, Teresa A. (2011). "Circadian activity rhythms and risk of incident dementia and mild cognitive impairment in older women". Annals of Neurology. 70 (5): 722–732. doi:10.1002/ana.22468. ISSN 1531-8249.

If your snoring is loud and uneven, erupts in snorts, or you sound like you're catching your breath or there are gaps in your breathing, these are signs of obstructive sleep apnea, the most severe type of sleep-disordered breathing. People with sleep apnea stop breathing repeatedly during their sleep because of a blockage in the mouth or throat, most commonly the soft tissues in the back of the throat, which collapse and close off.
A nocturnal movement disorder, restless leg syndrome can feel like itchiness, tingling, or prickling that makes you feel like you have to move your legs. Your legs may also move without your control while you sleep. You may or may not be aware of waking during the night, but restless leg syndrome causes sleep problems by preventing deep, restful sleep.
Competence in sleep medicine requires an understanding of a myriad of very diverse disorders, many of which present with similar symptoms 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 hypersomnia, Kleine–Levin syndrome, menstrual-related hypersomnia, idiopathic recurrent stupor, or circadian rhythm disturbances.[52] Another common complaint is insomnia, a set of symptoms which can have a great many different causes, physical and mental. Management in the varying situations differs greatly and cannot be undertaken without a correct diagnosis.[citation needed]
A nocturnal movement disorder, restless leg syndrome can feel like itchiness, tingling, or prickling that makes you feel like you have to move your legs. Your legs may also move without your control while you sleep. You may or may not be aware of waking during the night, but restless leg syndrome causes sleep problems by preventing deep, restful sleep.
If sleeping with a mask on doesn't work for you, other options are surgery; oral appliances; and newer, minimally invasive outpatient surgical treatments. These include the Pillar procedure, which involves using permanent stitches to firm up the soft palate; coblation, which uses radiofrequency to shrink nasal tissues; and even use of a carbon dioxide laser to shrink the tonsils.
Another systematic review noted 7-16% of young adults suffer from delayed sleep phase disorder. This disorder reaches peak prevalence when people are in their 20s.[57] Between 20 and 26% of adolescents report a sleep onset latency of >30 minutes. Also, 7-36% have difficulty initiating sleep.[59] Asian teens tend to have a higher prevalence of all of these adverse sleep outcomes than their North American and European counterparts.[59]
People who have insomnia don't feel as if they get enough sleep at night. They may have trouble falling asleep or may wake up frequently during the night or early in the morning. Insomnia is a problem if it affects your daytime activities. Insomnia has many possible causes, including stress, anxiety, depression, poor sleep habits, circadian rhythm disorders (such as jet lag), and taking certain medications.
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.
In addressing sleep disorders and possible solutions, there is often a lot of buzz surrounding melatonin. Research suggests that melatonin is useful in helping people to fall asleep faster (decreased sleep latency), to stay asleep longer, and to experience improved sleep quality. In order to test this, a study was conducted that compared subjects that had taken Melatonin to subjects that had taken a placebo pill in subjects with primary sleep disorders. Researchers assessed sleep onset latency, total minutes slept, and overall sleep quality in the Melatonin and placebo groups to note the differences. In the end, researchers found that melatonin decreased sleep onset latency, increased total sleep time, and improved quality of sleep significantly more than the placebo group.[49][50]
The most common sleep disorder is insomnia.[2] Others are sleep apnea, narcolepsy and hypersomnia (excessive sleepiness at inappropriate times), sleeping sickness (disruption of sleep cycle due to infection), sleepwalking, and night terrors. Management of sleep disturbances that are secondary to mental, medical, or substance abuse disorders should focus on the underlying conditions.
As suggested by its name, PLMD is an involuntary movement disorder. (An older name, nocturnal myoclonus , is rarely used anymore.) People with this problem experience sudden, involuntary leg movements during the night, such as kicking or jerking. The difference between this and restless leg syndrome is that, unless the kicking wakes you up, you don't know you're doing it. You don't experience the tingling and discomfort that leads you to consciously move your legs, as with restless leg syndrome. At least 80 percent of people with restless leg syndrome have PLMD, but the reverse isn't true.
Both night terrors and sleepwalking arise during NREM sleep and occur most often in children between the ages of 3 and 5 years old. A night terror can be dramatic: Your child may wake up screaming, but unable to explain the fear. Sometimes children who have night terrors remember a frightening image, but often they remember nothing. Night terrors are often more frightening for parents than for their child. Sleepwalkers can perform a range of activities -- some potentially dangerous, like leaving the house -- while they continue to sleep.
Get back to sleep when you wake up at night. Whether you have a sleep disorder or not, it’s normal to wake briefly during the night. If you’re having trouble getting back to sleep, try focusing on your breathing, meditating, or practicing another relaxation technique. Make a note of anything that’s worrying you and resolve to postpone worrying about it until the next day when it will be easier to resolve.
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.
In addition, an evidence-based synopses suggests that the sleep disorder, idiopathic REM sleep behavior disorder (iRBD), may have a hereditary component to it. A total of 632 participants, half with iRBD and half without, completed self-report questionnaires. The results of the study suggest that people with iRBD are more likely to report having a first-degree relative with the same sleep disorder than people of the same age and sex that do not have the disorder.[19] More research needs to be conducted to gain further information about the hereditary nature of sleep disorders.
Chronic sleep disorders in childhood, which affect some 70% of children with developmental or psychological disorders, are under-reported and under-treated. Sleep-phase disruption is also common among adolescents, whose school schedules are often incompatible with their natural circadian rhythm. Effective treatment begins with careful diagnosis using sleep diaries and perhaps sleep studies. Modifications in sleep hygiene may resolve the problem, but medical treatment is often warranted.[35]

Insomnias This type of sleep disorder involves the inability to fall asleep or stay asleep. MORE>>Hypersomnias Hypersomnias are a group of sleep disorders that causes a person to be excessively sleepy. People with a hypersomnia may fall asleep at times that are inconvenient or even dangerous, such as at work or while driving. MORE>>Sleep Related Breathing Disorders Sleep disorders that involve difficulty breathing during sleep are classified as sleep related breathing disorders. Obstructive sleep apnea is the most common disorder of this type, however there are a number of variations of sleep apnea. MORE>>Circadian Rhythm Sleep-Wake Disorders Conditions in which the sleep times are out of alignment. A patient with one of these disorders does not follow the normal sleep times at night. MORE>>Parasomnias Parasomnias are a group of sleep disorders that involve unwanted events or experiences that occur while you are falling asleep, sleeping or waking up. MORE>>Sleep Movement Disorders This classification of sleep disorders includes conditions that cause movement during or prior to sleep. These disorders can make it difficult to fall asleep or stay asleep, or to get restful sleep. MORE>>
Stay cool at night. Make sure your bedroom is at the right temperature to help ensure a good night’s sleep. The National Sleep Foundation suggests setting the temperature between 60 and 67 degrees Fahrenheit for optimal sleep. Using cooling sheets and pillows can also help, especially for women in menopause who are experiencing hot flashes at night, says Dr. Alyssa Dweck, assistant clinical professor of obstetrics and gynecology at the Mount Sinai School of Medicine and co-author of “V is for Vagina.”
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