Causes of Sleep Disorders
Sleep disorders are very common and can result from a number of causes. Stress, illness, diet (e.g., caffeine, alcohol), and medications (e.g., antidepressants) all can cause sleep problems.
Genetics & Sleep Disorders
Narcolepsy is the only major sleep disorder with a known genetic cause (i.e., hereditary).
Night Shift Work & Sleep Disorders
An internal system of signals in the brain controls normal physical and mental function during the course of a 24-hour day. This system, which is called the biological clock, responds to external cues like sunshine and darkness and controls when a person sleeps (or feels sleepy). In most cases, the darkness of the night triggers sleepiness.
Night shift workers often experience sleep disorders, because they cannot sleep when they start to feel drowsy. Their biological clock tells their body to sleep while they are going to or at work. People who work at night are at an increased risk for heart conditions and digestive problems, as well as emotional and mental problems.
The inability to detect light and darkness may cause disruptions in the biological clock, which can result in sleep disorders.
Mental Illness & Sleep Disorders
Most patients with mental illness experience some type of sleep disorder. Depression often causes patients to wake up early in the morning, unable to go back to sleep.
Many physical illnesses and diseases cause sleep disorders. Difficulty sleeping can result from chemical changes in the body caused by disease or by the medications used to treat the disease.
About 50% of adults over the age of 65 have some type of sleep disorder. It is not clear whether this is a normal part of aging, or a result of medications.