People with insomnia have difficulty falling asleep, staying asleep, or both. They may take hours to fall asleep, wake up frequently in the middle of the night, or wake up too early in the morning. Instead of feeling refreshed and rested, people with insomnia wake up feeling tired and drowsy. It's also common for them to feel depressed, irritable, and have trouble concentrating during the day.
Not everyone needs the same amount of sleep to feel refreshed in the morning. Most adults require 8 hours of sleep each night. Some people only require 4 or 5 hours sleep a night, while others need 9 or 10 hours to feel rested. People over 60 typically only need 6 hours of sleep.
Insomnia is a common health problem that differs in severity, depending on how often it occurs. Insomnia may be:
- Intermittent (occurs infrequently)
- Acute (occurs short term, for three weeks or less)
- Chronic (occurs three times a night for a month or longer)
Approximately 25% of Americans report occasional problems sleeping and 10% of them have chronic insomnia. Over 50% of older adults are believed to experience insomnia, and women are twice as likely to experience insomnia as men.
There are two types of insomnia:
- Primary insomnia
Primary insomnia is sleeplessness of a month or longer that is not caused by any known problem, such as a medical or emotional condition. Primary insomnia typically results from a major or long-lasting stress or anxiety. After the problem is corrected, people with primary insomnia continue to experience insomnia, usually due to the poor sleep habits they developed during the time they had trouble sleeping (such as napping).
- Secondary insomnia
Approximately 80% of the people with insomnia have secondary insomnia, which is caused by another problem, such as a medical condition (arthritis or cancer), emotional condition (anxiety or depression), or pain.