What Is Insomnia?
Insomnia is the perception or complaint of inadequate or poor-quality sleep because of one or more of the following:
- Difficulty falling asleep
- Waking up frequently during the night with difficulty returning to sleep
- Waking up too early in the morning
- Unrefreshing sleep
Insomnia is not defined by the number of hours of sleep a person gets or how long it takes to fall asleep. Individuals vary normally in their need for, and their satisfaction with, sleep. Insomnia may cause problems during the day, such as tiredness, a lack of energy, difficulty concentrating, and irritability.
Insomnia can be classified as transient (short term), intermittent (on and off), and chronic (constant). Insomnia lasting from a single night to a few weeks is referred to as transient. If episodes of transient insomnia occur from time to time, the insomnia is said to be intermittent. Insomnia is considered to be chronic if it occurs on most nights and lasts a month or more.
What Causes Insomnia?
Certain conditions seem to make individuals more likely to experience insomnia. Examples of these conditions include:
- Advanced age (insomnia occurs more frequently in those over age 60)
- Female gender
If other conditions (such as stress, anxiety, a medical problem, or the use of certain medications) occur along with the above conditions, insomnia is more likely.
There are many causes of insomnia. Transient and intermittent insomnia generally occur in people who are temporarily experiencing one or more of the following:
- Environmental noise
- Extreme temperatures
- Change in the surrounding environment
- Sleep/wake schedule problems such as those due to jet lag
- Medication side effects
Chronic insomnia is more complex and often results from a combination of factors, including underlying physical or mental disorders. One of the most common causes of chronic insomnia is depression. Other underlying causes include arthritis, kidney disease, heart failure, asthma, sleep apnea, narcolepsy, restless legs syndrome, Parkinson’s disease, and hyperthyroidism. However, chronic insomnia may also be due to behavioral factors, including the misuse of caffeine, alcohol, or other substances; disrupted sleep/wake cycles as may occur with shift work or other nighttime activity schedules; and chronic stress.
In addition, the following behaviors have been shown to perpetuate insomnia in some people:
- Expecting to have difficulty sleeping and worrying about it
- Ingesting excessive amounts of caffeine
- Drinking alcohol before bedtime
- Smoking cigarettes before bedtime
- Excessive napping in the afternoon or evening
- Irregular or continually disrupted sleep/wake schedules
These behaviors may prolong existing insomnia, and they can also be responsible for causing the sleeping problem in the first place. Stopping these behaviors may eliminate the insomnia altogether.
Who Gets Insomnia?
Insomnia is found in males and females of all age groups, although it seems to be more common in females (especially after menopause) and in the elderly. The ability to sleep, rather than the need for sleep, appears to decrease with advancing age.