Sleep disorders - overview
Sleep disorders are problems with sleeping. These include:
- Trouble falling or staying asleep
- Falling asleep at the wrong times
- Too much sleep
- Abnormal behaviors during sleep
There are more than 100 different sleeping and waking disorders. They can be grouped into four main categories:
- Problems falling and staying asleep (insomnia)
- Problems staying awake (excessive daytime sleepiness)
- Problems sticking to a regular sleep schedule (sleep rhythm problem)
- Unusual behaviors during sleep (sleep-disruptive behaviors)
PROBLEMS FALLING AND STAYING ASLEEP
Insomnia includes trouble falling asleep or staying asleep. Episodes may come and go, last up to 3 weeks (be short-term), or be long-lasting (chronic).
PROBLEMS STAYING AWAKE
People with excessive daytime sleepiness feel tired during the day. Symptoms that are not caused by a lack of sleep or interrupted sleep are called hypersomnia.
Causes of this problem include:
- Medical conditions, such as fibromyalgia and low thyroid function
- Mononucleosis or other viral illnesses
- Narcolepsy and other sleep disorders
- Obesity, especially if it causes obstructive sleep apnea
When no cause for the sleepiness can be found, it is called idiopathic hypersomnia.
PROBLEMS STICKING TO A REGULAR SLEEP SCHEDULE
Problems may also occur when you do not stick to a regular sleep and wake schedule. This occurs when people travel between time zones and with shift workers who are on changing schedules, especially nighttime workers.
Disorders that involve a disrupted sleep schedule include:
- Irregular sleep-wake syndrome
- Jet lag syndrome
- Paradoxical insomnia (the person sleeps a different amount than they think they do)
- Shift work sleep disorder
Abnormal behaviors during sleep are called parasomnias. They are fairly common in children and include:
- Sleep terrors
- REM sleep-behavior disorder (a person moves during REM sleep and may act out dreams)
Sateia MJ. International classification of sleep disorders-third edition: highlights and modifications. Chest. 2014;146:1387-1394. PMID 25367475 www.ncbi.nlm.nih.gov/pubmed/25367475.
Wakefield TL, Lam DJ, Ishman SL. Sleep apnea and sleep disorders. In: Flint PW, Haughey BH, Lund VJ, et al., eds. Cummings Otolaryngology: Head & Neck Surgery. 6th ed. Philadelphia, PA: Elsevier Mosby; 2015:chap 18.