What Is Insomnia?
Insomnia (in-SOM-ne-ah) is a common condition in which you have trouble falling or staying asleep. This condition can range from mild to severe, depending on how often it occurs and for how long.
Insomnia can be chronic (ongoing) or acute (short-term). Chronic insomnia means having symptoms at least 3 nights a week for more than a month. Acute insomnia lasts for less time.
Some people who have insomnia may have trouble falling asleep. Other people may fall asleep easily but wake up too soon. Others may have trouble with both falling asleep and staying asleep.
As a result, insomnia may cause you to get too little sleep or have poor-quality sleep. You may not feel refreshed when you wake up.
There are two types of insomnia. The most common type is called secondary or comorbid insomnia. This type of insomnia is a symptom or side effect of some other problem.
More than 8 out of 10 people who have insomnia are believed to have secondary insomnia. Certain medical conditions, medicines, sleep disorders, and substances can cause secondary insomnia.
In contrast, primary insomnia isn’t due to a medical problem, medicines, or other substances. It is its own disorder. A number of life changes can trigger primary insomnia, including long-lasting stress and emotional upset.
Insomnia can cause excessive daytime sleepiness and a lack of energy. It also can make you feel anxious, depressed, or irritable. You may have trouble focusing on tasks, paying attention, learning, and remembering. This can prevent you from doing your best at work or school.
Insomnia also can cause other serious problems. For example, you may feel drowsy while driving, which could lead to an accident.
Secondary insomnia often resolves or improves without treatment if you can stop its cause—especially if you can correct the problem soon after it starts. For example, if caffeine is causing your insomnia, stopping or limiting your intake of the substance may cause your insomnia to go away.
Lifestyle changes, including better sleep habits, often help relieve acute insomnia. For chronic insomnia, your doctor may recommend a type of counseling called cognitive-behavioral therapy or medicines.
What Causes Insomnia?
Secondary insomnia is the symptom or side effect of another problem. This type of insomnia often is a symptom of an emotional, neurological, or other medical or sleep disorder.
Emotional disorders that can cause insomnia include depression, anxiety, and posttraumatic stress disorder. Alzheimer’s disease and Parkinson’s disease are examples of common neurological disorders that can cause insomnia.
A number of other conditions also can cause insomnia, such as:
- Conditions that cause chronic pain, such as arthritis and headache disorders
- Conditions that make it hard to breathe, such as asthma and heart failure
- An overactive thyroid
- Gastrointestinal disorders, such as heartburn
- Sleep disorders, such as restless legs syndrome and sleep-related breathing problems
- Menopause and hot flashes
Secondary insomnia also may be a side effect of certain medicines. For example, certain asthma medicines, such as theophylline, and some allergy and cold medicines can cause insomnia. Beta blockers also may cause the condition. These medicines are used to treat heart conditions.
Commonly used substances also may cause insomnia. Examples include caffeine and other stimulants, tobacco or other nicotine products, and alcohol or other sedatives.
Primary insomnia isn’t a symptom or side effect of another medical condition. This type of insomnia usually occurs for periods of at least 1 month.
A number of life changes can trigger primary insomnia. It may be due to major or long-lasting stress or emotional upset. Travel or other factors, such as work schedules that disrupt your sleep routine, also may trigger primary insomnia.
Even if these issues are resolved, the insomnia may not go away. Trouble sleeping may persist because of habits formed to deal with the lack of sleep. These habits may include taking naps, worrying about sleep, and going to bed early.
Researchers continue to try to find out whether some people are born with a greater chance of having primary insomnia.
Who Is At Risk for Insomnia?
Insomnia is a common disorder. One in 3 adults has insomnia sometimes. One in 10 adults has chronic insomnia.
Insomnia affects women more often than men. The condition can occur at any age. However, older adults are more likely to have insomnia than younger people.
People who may be at higher risk for insomnia include those who:
- Have a lot of stress.
- Are depressed or who have other emotional distress, such as divorce or death of a spouse.
- Have lower incomes.
- Work at night or have frequent major shifts in their work hours.
- Travel long distances with time changes.
- Have certain medical conditions or sleep disorders that can disrupt sleep. For more information, see “What Causes Insomnia?”
- Have an inactive lifestyle.
Young and middle-aged African Americans also may be at increased risk for insomnia. Research shows that, compared to Whites, it takes African Americans longer to fall asleep. They also have lighter sleep, don’t sleep as well, and take more naps. Sleep-related breathing problems also are more common among African Americans.
What Are the Signs and Symptoms of Insomnia?
The main symptom of insomnia is trouble falling and/or staying asleep, which leads to lack of sleep. If you have insomnia, you may:
- Lie awake for a long time before you fall asleep
- Sleep for only short periods
- Be awake for much of the night
- Feel as if you haven’t slept at all
- Wake up too early
The lack of sleep also can cause other symptoms. You may wake up feeling tired or not well-rested, and you may feel tired during the day. You also may have trouble focusing on tasks. Insomnia can cause you to feel anxious, depressed, or irritable.
Insomnia may affect your daily activities and cause serious problems. For example, you may feel drowsy while driving. Driving while sleepy leads to more than 100,000 car crashes each year. In older women, research shows that insomnia raises the risk of falling.
If insomnia is affecting your daily activities, see your doctor. Treatment may help you avoid symptoms and problems related to the condition. Also, poor sleep may be a sign of other health problems. Finding and treating those problems could improve both your health and your sleep.
How Is Insomnia Diagnosed?
Usually, your doctor will diagnose insomnia based on your medical and sleep histories and a physical exam. He or she also may recommend a sleep study. For example, you may have a sleep study if the cause of your insomnia is unclear.
To find out what’s causing your insomnia, your doctor may ask whether you:
- Have any new or ongoing health problems
- Have painful injuries or health conditions, such as arthritis
- Take any medicines, either over-the-counter or prescription
- Have symptoms or a history of depression, anxiety, or psychosis
- Are coping with any very stressful life events, such as divorce or death
Your doctor also may ask questions about your work and leisure habits. For example, he or she may ask about your work and exercise routines; your use of caffeine, tobacco, and alcohol; and your long-distance travel history. Your answers may give clues about what’s causing your insomnia.
Your doctor also may ask whether you have any new or ongoing work or personal problems or other stresses in your life. Also, he or she may ask whether you have other family members who have sleep problems.
To get a better sense of your sleep problem, your doctor will ask you details about your sleep habits. Before your visit, think about how to describe your problems, including:
- How often you have trouble sleeping and how long you’ve had the problem
- When you go to bed and get up on workdays and days off
- How long it takes you to fall asleep, how often you wake up at night, and how long it takes to fall back asleep
- Whether you snore loudly and often or wake up gasping or feeling out of breath
- How refreshed you feel when you wake up, and how tired you feel during the day
- How often you doze off or have trouble staying awake during routine tasks, especially driving
To find out what’s causing or worsening your insomnia, your doctor also may ask you:
- Whether you worry about falling asleep, staying asleep, or getting enough sleep
- What you eat or drink, and whether you take medicines before going to bed
- What routine you follow before going to bed
- What the noise level, lighting, and temperature are like where you sleep
- What distractions, such as a TV or computer, are in your bedroom
To help your doctor, consider keeping a sleep diary for 1 or 2 weeks. Write down when you go to sleep, wake up, and take naps. (For example, you might note: Went to bed at 10 a.m.; woke up at 3 a.m. and couldn’t fall back asleep; napped after work for 2 hours.)
Also write down how much you sleep each night, as well as how sleepy you feel at various times during the day.
You can find a sample sleep diary in the National Heart, Lung, and Blood Institute’s“Your Guide to Healthy Sleep.”
Your doctor will do a physical exam to rule out other medical problems that might cause insomnia. You also may need blood tests to check for thyroid problems or other conditions that can cause sleep problems.
Your doctor may recommend a sleep study called a polysomnogram (PSG) if he or she thinks an underlying sleep disorder is causing your insomnia.
A PSG usually is done while you stay overnight at a sleep center. A PSG records brain electrical activity, eye movements, heart rate, breathing, muscle activity, blood pressure, and blood oxygen levels.