Insomnia is a problem with sleep. Causes include stress, environmental factors, medications, hormonal shifts, aging, and physical or mental illnesses.
Insomnia refers to trouble sleeping. People with insomnia may have trouble falling asleep, trouble staying asleep, or may wake early and be unable to fall back to sleep. They may also suffer from non-refreshing sleep, in which enough hours are spent sleeping, but the sleep quality is poor and the person still feels tired during the day.
Insomnia may be considered chronic if it occurs at least three days every week for at least a month. Shorter durations or less frequent episodes are referred to as acute insomnia.
There are a variety of potential causes of insomnia, and there are different causes of acute and chronic insomnia. The causes of acute insomnia include:
• Changes in your sleep schedule (such as jet lag or shift work)
• Significant life stresses (such as the death of a loved one)
• Poor sleep environment
• Certain medications, including over-the-counter medications (such as cold and allergy treatments) as well as prescription medications
• Caffeine, nicotine, or alcohol late in the day
• Pain or illness
Caffeine and nicotine are stimulants, meaning that they act to energize you and keep you awake. Alcohol is a sedative, meaning that it may help you to fall asleep at first. However, alcohol interferes with the quality of your sleep, so it won’t be as refreshing, and can also lead to waking partway through the night, as the alcohol is metabolized by the liver. People who drink alcohol in order to fall asleep may be unaware that this is why they still feel tired in the morning.
The causes of chronic insomnia include:
• Emotional illness, such as depression or anxiety
• Chronic stress
• Physical pain, such as from an illness like arthritis
• Habitual use of caffeine, nicotine, or alcohol late in the day
One major risk factor for insomnia is age; as people get older, they become more likely to suffer from problems sleeping. There are many reasons for this. Older people often experience less restful sleep, and their biological clock shifts, meaning that they need to go to bed earlier and wake earlier; if they continue with the same bedtime but wake earlier, they may become sleep-deprived. Additionally, older people commonly get less exercise; exercise is known to promote later sleep.
Older people are also more likely to have medical conditions like arthritis, which can cause pain and interfere with sleep, and are also more likely to be taking medications that may interfere with sleep. Hot flashes related to menopause are a common cause of insomnia in older women.
In general, women are more likely to suffer from insomnia than are men, which may be related to their normal hormonal shifts throughout the month. Those who travel frequently across time zones or do shift work (and work the night shift, or frequently change between the day and the night shift) are also more likely to have sleep problems. Those with mental health disorders, including depression and anxiety, and those who are experiencing stress (such as the death of a loved one, the loss of a job, a divorce, or moving) may also experience insomnia.
Centers for Disease Control and Prevention (CDC). “Sleep and Sleep Disorders.” CDC website (2015). http://www.cdc.gov/Sleep/index.html
National Institute of Neurological Disorders and Stroke (NINDS). “Brain Basics: Understanding Sleep.” NINDS website (2014). http://www.ninds.nih.gov/disorders/brain_basics/understanding_sleep.htm
Mayo Clinic Staff. “Insomnia: Definition.” Mayo Clinic website (2014). http://www.mayoclinic.org/diseases-conditions/insomnia/basics/definition/con-20024293