It is characterized by brief interruptions in breathing during sleep, despite the effort to breathe. It is also associated with a drop in blood oxygen saturation. These interruptions in breathing are called "apneas" (which literally means "without breath") and have to occur for over ten seconds per episode to be classified as an apnea.
The individual with OSA is not always aware of having interruptions in breathing, even when waking up. It is usually recognized as a problem by the individual's bed-partner or other family members. Others witness heavy snoring or that the individual struggles to breathe while sleeping. OSA is very often accompanied with snoring. Symptoms may be present for years without being identified. Symptoms include daytime sleepiness and fatigue due to significant levels of sleep disturbance. Without a regular bed-partner to notice and make them aware of their symptoms, individuals who generally sleep alone are often not aware of the condition.
Certain mechanical and structural problems in the airway cause the interruptions in breathing during sleep. The throat muscles and tongue relaxes and sags causing a partial or full obstruction in the airway.OSA very often occurs among obese people because of excessive fatty tisssue narrowing the airway. This results in heavy snoring, periods of not breathing and frequent arousals (causing abrupt changes from deep sleep to light sleep).
Insomnia is generally thought of as both a medical sign and a symptom that can accompany a number of sleep, medical, and psychiatric disorders often characterized by a continuous inability to fall asleep and/or stay asleep or having sleep of poor quality. Functionality usually becomes impaired whilst awake. Insomnia can occur at any age, but it is most common in the elderly. Insomnia can be short term (up to three weeks) or long term (above 3–4 weeks); it can eventually cause memory problems, depression, irritability and an increased risk of heart disease and motor vehicle related accidents (caused by excessive daytime sleepiness).
Individuals that suffer from insomnia could complain of prolonged sleep onset latency (difficulty in falling asleep), sleep maintenance being easily disturbed or experiencing non-refreshing sleep.
Often insomniacs turn to sleeping pills, which may help, but could also lead to dependency or addiction if constantly used over a long period of time. A very useful therapy for insomnia is cognitive behavioral therapy. One is then able to get to the root of the problem and be retrained into a regular sleep pattern.
It is most commonly felt in the legs, but can also affect the arms, torso and head. Moving the body part affected by the sensations, provides temporary relief.
RLS sensations range from pain or an aching in the muscles, to "an itch you can't scratch," an unpleasant "tickle that won't stop," or even a feeling that your skin is "crawling". A lot of individuals with RLS suffer from periodic limb movement disorder (limbs jerking during sleep), which is usually a prominant indicator of the disorder. It can also be caused by low iron levels.
PLMD should not be confused with restless leg syndrome (RLS), although PLMD occurs in most individuals suffering from RLS. RLS occurs while awake as well as when asleep, and when awake, there is a voluntary response to an uncomfortable feeling in the legs. PLMD on the other hand is involuntary, and the patient is usually not aware of these movements at all.
People with narcolepsy experience frequent excessive daytime sleepiness. Those with narcolepsy generally experience the REM stage of sleep within 5 minutes of sleep latency, while people who don't have narcolepsy (unless they are severely sleep deprived) do not experience REM until after a period of slow-wave sleep, which lasts for more or less the first hour of a sleep cycle. Another common symptom of narcolepsy is cataplexy, a sudden and brief episode of muscle weakness while in a full state of consciousness, often triggered by emotions such as laughing, crying, terror, etc. Cataplexy occurs in about 70% of people who have narcolepsy.