What is insomnia?

Insomnia is a sleep disorder in which people have one or more of the following symptoms:

  • Difficulty falling asleep.
  • Waking up often during the night and having trouble going back to sleep.
  • Waking up too early in the morning.
  • Having sleep that is not refreshing.

Who gets insomnia?

Approximately 50% of adults experience occasional bouts of insomnia, and 1 in 10 complain of chronic insomnia. Insomnia is approximately twice as common in women as in men, and is more common in older than younger people.

Kinds of insomnia

There are two kinds of insomnia:

  • Primary insomnia means that a person is having sleep problems that are not directly associated with any other health condition or problem.
  • Secondary (co-morbid) insomnia means that a person is having sleep problems because of something else, such as a health condition (for example, asthma, depression, arthritis, cancer, or heartburn), pain, medicine they are taking, or a substance they are using (such as alcohol).

Insomnia also varies in how long it lasts and how often it occurs. Insomnia can be short-term (acute insomnia) or can last a long time (chronic insomnia). It can also come and go, with periods of time when a person has no sleep problems. Acute insomnia can last from 1 night to a few weeks. Insomnia is called chronic when a person has insomnia at least 3 nights a week for a month or longer.

There are still other ways to classify insomnia. One of the most common forms of insomnia is called psychophysiological ("mind-body") insomnia. This is a disorder of learned, sleep-preventing associations, such as not being able to sleep because either your body or your mind is not relaxed. People with this insomnia usually have excessive, daily worries about not being able to fall or stay asleep when desired and worry that their efforts to fall asleep will be unsuccessful. Many people with this condition are concerned that they will never have a good night of sleep again. Stress is the most common cause of psychophysiological insomnia. While sleep problems are common when going through a stressful event, some people continue to have sleep problems long after the stressful event is over. Sometimes the stress and sleep problems create an ongoing, worsening cycle of each problem.

In addition to stress, what are other causes of insomnia?

Causes of acute insomnia can include:

  • Other significant types of life stressors (job loss or change, death of a loved one, moving).
  • Illness.
  • Medications.
  • Emotional or physical discomfort.
  • Environmental factors such as noise, light, or extreme temperatures (hot or cold) that interfere with sleep.
  • Things that interfere with a normal sleep schedule (jet lag or switching from a day to night shift, for example).

Causes of chronic insomnia include:

  • Depression.
  • Chronic stress.
  • Pain or discomfort at night.

What are the symptoms of insomnia?

Symptoms of insomnia include sleepiness during the day, general tiredness, irritability, and problems with concentration or memory.