Sleep Disorders - Causes

In many cases, the cause of a sleep disorder is not known. In other cases, researchers know at least part of the reason the disorder occurs. Some examples include:

• Insomnia. Insomnia may be caused by emotional experiences or concerns such as marital problems, problems at work, feelings of guilt, or concerns about health. A person may become so distraught that sleep is impossible. Insomnia often becomes worse when patients worry about the condition. In such cases, the worry itself becomes another cause for the disorder.
• Hypersomnia. One possible cause of hypersomnia is restless legs syndrome. Restless legs syndrome is the name given to cramps and twitches a person may experience in the calves of the legs during sleep. These sensations may keep a person awake and lead to sleep episodes during the day.
• Narcolepsy. The cause of narcolepsy is currently not known.
• Sleep apnea. The most common cause of sleep apnea is blockage of the airways. The condition occurs most commonly in people who are over-weight. The snoring and gasping that are typical of apnea are caused by the person's trying to catch his or her breath. Less commonly, sleep apnea is caused by damage to the brainstem.
• Circadian rhythm sleep disorders. Circadian rhythm sleep disorders are caused when people are forced to adjust to new dark/light patterns. An example is a worker whose assignment is changed from the day shift to the night shift. The worker must learn how to sleep when it's light out and to work when it's dark out.

The causes of most parasomnias are not well understood. In some cases, severe stress may be responsible for the condition. In other cases, it is not clear what the cause for the disorder is.