Sleep disorder is a medical disorder with any changes in the normal sleep pattern that includes difficulty falling or staying asleep (insomnia), falling asleep at inappropriate times and oversleeping. Some sleeping problems last less than 3 weeks and resolve without treatment. Chronic sleep disorders last more than 3 weeks are much more persistent and require treatment.
Different types of sleep disorders affect millions of people around the world. Approximately about 50 to 70 million adult Americans suffer from chronic sleep disorders like chronic insomnia and in addition many sleep disorders remain undiagnosed and untreated. More than two-thirds of older adults and children experience and report some sleep problems, however only a few of them have been diagnosed.
Sleep disorders are usually not serious, but some of them can interfere with normal physical and mental functioning and even be life threatening. They may impair quality of life, enjoyment as well as cause poor work performance, social embarrassment or memory problems. Drowsy drivers cause 1,5% of all crashes each year.
Causes of sleep disorders are varied and include different medical conditions, psychological disorders, situational stress, changes in sleep environment and hours, poor bedtime habits, medications, drugs, alcohol and genetics. The average amount of sleep is 7-1/2 hours but it varies from person to person.
There are several common tests for diagnosing sleep disorders such as:
- Polysomnogram (PSG) or overnight sleep study that includes the measurements of the electrical activities of brain (electroencephalogram), heart (electrocardiogram) and the movements of the muscles (electromyogram) and eyes (electro-oculogram);
- Epworth sleepiness scale is a sleep questionnaire;
- Multiple sleep latency test (MSLT) measures how long it takes for somebody to fall asleep;
- Repeated test of sustained wakefulness (RTSW) measures the length of time needed to fall asleep by challenging the personís ability to stay awake;
- Blood test can be very helpful as well.
Common types of sleep disorders are:
Insomnia is a repeated sleeplessness that manifests as being unable to fall or stay asleep. Sleep quality tends to decrease with age and affects 15 to 17% of the population at any given time.
Insomnia is often associated with depression, anxiety, stress, mental illnesses and some medical conditions such as chronic pain, chronic obstructive pulmonary disease (COPD), congestive heart failure and women in menopause. Medications for high blood pressure, asthma and cold (over the counter drugs) as well as the stimulants such as caffeine and nicotine are also associated with insomnia.
There are three types of insomnia:
- Transient insomnia lasts a few nights to a few weeks;
- Acute or short-term insomnia happens from time to time and it lasts between three weeks to six months;
- Chronic insomnia is long-term insomnia that lasts from months to years.
Sleep apnea is a sleep disorder in which people stop breathing from a few seconds to minutes repeatedly or shallow breath during their sleep. It is usually a chronic condition that may be often undiagnosed and most of the time is first recognized by a bed partner witnessing the individual during episodes.
There are three types of sleep apnea:
- Obstructive sleep apnea occurs when throat muscles relax and the airway becomes obstructed causing breathing pauses or shallow breathing. It may affect anyone although is most common among men, older adults and people who are overweight. People usually complain about morning headaches, dry mouth, loud snoring, fatigue, daytime sleepiness, depression, heartburn and poor concentration.
- Central sleep apnea occurs in people with severe lower brain stem lesions when the brain doesnít send proper signals to the muscles that control breathing. People with central sleep apnea temporarily stop breathing during sleep.
- Complex sleep apnea is a combination of both obstructive and central sleep apneas.
Untreated sleep apnea may have very serious consequences for the health of people increasing the risks for high blood pressure, heart attack, stroke, diabetes and work or driving accidents. Lifestyle changes, surgery and breathing devices may be successful treatment for many people.
Restless leg syndrome is a sleep disorder characterized by painful or uncomfortable sensations (paresthesias) in the legs accompanied by an irresistible urge for movement. These sensations are described as tingling, burning, creeping, crawling, pulling or even jerking. Sometimes, the sensations also occur in the arms and torso.
The exact cause of restless leg syndrome is unknown although genetic and environmental factors as well as some medications and medical conditions may contribute to this disorder. Parkinson disease, kidney failure, rheumatoid arthritis, diabetes, iron deficiency and pregnancy are associated with RLS.
RLS can begin at any age including childhood, adolescence or adulthood. It affects both sexes and can range from mild to severe form. RLS is often misdiagnosed or undiagnosed.
RLS interferes with sleep and quality of life what can cause depression and other health problems. RLS treatment includes some lifestyle changes and medicines.
Narcolepsy is a chronic sleep disorder characterized by intermittent and uncontrollable episodes of falling asleep during the daytime. It belongs to the group of sleep disorders called hypersomnia that have excessive daytime sleepiness (EDS) as a primary symptom. A person with narcolepsy usually feels drowsy and may take naps without warning at inappropriate times and places several times a day even when they sleep well at night.
People with narcolepsy have disturbed sleep patterns and often wake up during the night. According to scientific research, people with narcolepsy have low levels of a protein called hypocretin that helps the brain stay alert. Narcolepsy affects both sexes, with a slightly higher risk among men. It can be socially disabling and cause depression.
There are two types of narcolepsy:
- narcolepsy without cataplexy;
- narcoplexy with cataplexy (about 65% of people with narcolepsy also experience cataplexy);
Cataplexy is the episode of muscle weakness usually triggered by strong emotions such as laughter, surprise, fear, anger, embarrassment etc.
Cataplexy can be:
- partial, when affecting a specific muscle group ( e.g. face or knees), or
- complete, when affecting the entire body.
These episodes are usually brief with complete recovery.
Other symptoms include:
- sleep paralysis (temporary being unable to move or speak shortly before falling asleep or after waking up);
- sleep-onset hallucinations (dream like visions or sounds during onset of sleep or awakening)
- automatic behavior (a behavior performed without awareness).
Narcolepsy is treatable with lifestyle changes and medications.