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insomnia





Contents
  • What causes insomnia?
  • Who is at risk?
  • Signs and symptoms
  • Diagnosis
  • Treatment
  • Insomnia is a condition in which you have trouble falling or staying asleep. Some people with insomnia may fall asleep easily but wake up too soon. Other people may have the opposite problem, or they have trouble with both falling asleep and staying asleep. The end result is poor-quality sleep that doesn't leave you feeling refreshed when you wake up.


    Types of insomnia

    There are two types of insomnia. The most common type is called secondary insomnia. More than 8 out of 10 people with insomnia are believed to have secondary insomnia. Secondary means that the insomnia is a symptom or a side-effect of some other problem. Some of the problems that can cause secondary insomnia include:
    • Certain illnesses, such as some heart and lung diseases
    • Pain, anxiety, and depression
    • Medicines that delay or disrupt sleep as a side-effect
    • Caffeine, tobacco, alcohol, and other substances that affect sleep
    • Another sleep disorder, such as restless legs syndrome; a poor sleep environment; or a change in sleep routine
    In contrast, primary insomnia is not a side-effect of medicines or another medical problem. It is its own disorder, and generally persists for least 1 month or longer.


    Overview

    Insomnia is a common health problem. It can cause excessive daytime sleepiness and a lack of energy. Long-term insomnia can cause you to feel depressed or irritable; have trouble paying attention, learning, and remembering; and not do your best on the job or at school. Insomnia also can limit the energy you have to spend with friends or family.

    Insomnia can be mild to severe depending on how often it occurs and for how long. Chronic insomnia means having symptoms at least 3 nights per week for more than a month. Insomnia that lasts for less time is known as short-term or acute insomnia.


    Outlook

    Secondary insomnia often resolves or improves without treatment if you can eliminate its cause. This is especially true if the problem can be corrected soon after it starts. Better sleep habits and lifestyle changes often help relieve insomnia. You may need to see a doctor or sleep specialist to get the best relief for insomnia that is persistent or for which the cause of the sleep problem is unclear.





    What causes insomnia?


    Causes of secondary insomnia

    Secondary insomnia is often a symptom of an emotional, neurological, or other medical disorder, or of another sleep disorder.

    The emotional disorders that can cause secondary insomnia include depression, anxiety, and posttraumatic stress disorder. Alzheimer's disease and Parkinson's disease are examples of common neurological disorders that can cause secondary insomnia.

    A number of other diseases and conditions can cause secondary insomnia, including:
    • Conditions that cause chronic pain, such as arthritis and headache disorders
    • Conditions that cause difficulty breathing, such as asthma or heart failure
    • Overactive thyroid
    • Gastrointestinal disorders, such as heartburn
    • Stroke
    Sleep disorders, such as restless legs syndrome, also can cause secondary insomnia. In addition, secondary insomnia can be a side-effect of certain medicines or commonly used substances, including:
    • Caffeine or other stimulants
    • Tobacco or other products with nicotine
    • Alcohol or other sedatives
    • Certain asthma medicines (for example, theophylline) and some allergy and cold medicines
    • Beta blockers (medicines used to treat heart conditions)

    Causes of primary insomnia

    Primary insomnia is not due to another medical or emotional condition and typically occurs for periods of at least 1 month. Whether some people are born with a greater chance of having insomnia is not clear yet. A number of life changes can trigger primary insomnia, including:
    • Major or long-lasting stress and emotional upset
    • Travel or other factors such as work schedules that disrupt your sleep routine
    • Even after these causes go away, the insomnia might stay. Trouble sleeping may persist because of habits formed to deal with the lack of sleep.
    These habits include taking naps, worrying about sleep, or going to bed early.


    Who is at risk for insomnia?

    Insomnia is a common disorder. One in 3 adults occasionally has insomnia. One in 10 adults has chronic insomnia. Insomnia affects women more often than men, and it can occur at any age. However, older adults are more likely to have insomnia than younger people. People especially prone to insomnia include those who are:
    • Under a lot of stress
    • Depressed or who have other emotional distress
    • Working at night or having frequent major shifts in their work hours
    • Traveling long distances with time changes (jet lag)

    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. The lack of sleep can cause others symptoms, such as:
    • Waking up feeling tired or not well rested
    • Feeling tired or very sleepy during the day
    • Having trouble focusing on tasks
    • Feeling anxious, depressed, or irritable

    How is insomnia diagnosed?

    Your doctor will usually diagnose insomnia based on your medical history, sleep history, a physical exam, and a sleep study if the cause of your insomnia is unclear.


    Medical history

    Your doctor will ask questions to find out whether there is a medical cause for your insomnia. These include questions about whether you:
    • Have any new or ongoing health problems
    • Have painful injuries or health conditions (such as arthritis)
    • Take any medicines (over-the-counter or prescription)
    Other questions are aimed at finding work or leisure habits that might be causing your insomnia. Your doctor may ask about your work and exercise routines; your use of caffeine, tobacco, or alcohol; and your long-distance travel history.

    Your doctor also may ask whether you have any new or ongoing work, personal problems, or other stresses in your life. In addition, you may be asked whether you have other family members with sleep problems.


    Sleep history

    To get a better sense of your sleep problem, your doctor will ask you details about your sleep habits, including:
    • How often you have trouble sleeping and how long the problem has persisted
    • 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
    • If you snore loudly and frequently, 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
    You may be asked to keep a sleep diary for 1 to 2 weeks so you can answer these questions easily. Your bed partner may help you keep the sleep diary.

    To see what might be causing or worsening your insomnia, your doctor will also 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, might be in your bedroom

    Physical exam

    Your doctor will do a physical exam to rule out other medical problems that might cause insomnia. You may also need blood tests to check for thyroid problems or other conditions that can cause sleep problems.


    Sleep study (polysomnogram)

    A polysomnogram is a recording of your breathing, movements, heart function, and brain activity during sleep. For this study, you sleep overnight at a special sleep center. Your doctor usually will recommend a sleep study if you have signs of another sleep disorder, such as sleep apnea or restless legs syndrome.


    How is insomnia treated?

    Making lifestyle changes that make it easier to fall asleep and/or stay asleep can often relieve insomnia. For longer lasting insomnia, a type of counseling called cognitive-behavioral therapy can help relieve the anxiety linked to your sleep problem. Anxiety tends to prolong the insomnia. Several medicines also can help relieve insomnia and re-establish a regular sleep schedule.


    Lifestyle changes

    To relieve insomnia, you should avoid substances that make it worse and have good bedtime habits that make it easier to fall asleep and stay asleep. Make sure your bedroom is a comfortable temperature, dark, and quiet enough for sleep.

    Avoid substances such as:
    • Caffeine, tobacco, and other stimulants taken too close to bedtime (effects of caffeine can take as long as 8 hours to wear off).

    • Certain over-the-counter and prescription medicines that can disrupt sleep (for example, some cold and allergy medicines).

    • Alcohol. An alcoholic drink before bedtime may make it easier for you to fall asleep. But alcohol triggers sleep that tends to be lighter than normal and makes it more likely that you will wake up during the night.
    Good bedtime habits include:
    • Following a routine that helps you wind down and relax before bed, such as reading a book, listening to soothing music, or taking a hot bath.

    • Not exercising, eating heavy meals, or drinking a lot shortly before bedtime.

    • Making your bedroom sleep-friendly. Avoid bright lighting and minimize possible sleep distractions, such as a TV, computer, or pet.

    • Going to sleep around the same time each night and waking up around the same time each morning, even on weekends. If possible, avoid night shifts or alternating schedules at work and other causes of irregular sleep schedules.

    Cognitive-behavioral therapy

    Cognitive-behavioral therapy for insomnia targets the thoughts and actions that can disrupt sleep. Besides encouraging good sleep habits, this type of therapy may use several methods to relieve sleep anxieties, including:
    • Relaxation training and biofeedback at bedtime to reduce anxiety. These strategies help you better control your breathing, heart rate, muscles, and mood.

    • Replacing worries about not being able to fall asleep with more positive thinking that links being in bed with being asleep. This method also teaches you what to do if you're unable to fall asleep within a reasonable period.

    • Talking with a therapist individually or in group sessions to help you consider your thoughts and feelings about sleep. This method may encourage you to describe thoughts racing through your mind in terms of how they look, feel, and sound. The goal is for your mind to settle down and stop racing.

    • Limiting the time you spend in bed while awake. This method involves setting a sleep schedule and, at first, limiting total time in bed to the typical short length of time you're usually asleep. At first, this schedule may make you even more tired because some of the allotted time in bed will be taken up by difficulty sleeping. The resulting fatigue (tiredness) is intended to help you get to sleep more quickly. Gradually, the length of time spent in bed is increased until you get a full night of sleep.
    For success with this type of therapy, you may need to see a therapist who is skilled in this approach weekly over 2 to 3 months. Cognitive-behavioral therapy is as effective as prescription medicine for many types of chronic insomnia. It also may provide better long-term relief than medicine alone.


    Medicines

    Several medicines cause sleepiness. Doctors sometimes prescribe sleep-inducing medicine for 1 to 2 weeks to help establish a regular sleep schedule. Insomnia medicine helps you fall asleep, but can leave some people feeling unrefreshed or groggy in the morning. You may also be groggy and should exercise caution if you must get up before getting a full night's sleep of 7 to 8 hours while taking these medicines. The Food and Drug Administration (FDA) hasn't approved all insomnia medicines for continuous, long-term use. Your doctor can help you understand the benefits and potential problems if medicines will be needed for long periods.

    Some people use natural remedies to treat their insomnia. These remedies include melatonin and L-tryptophan supplements and valerian teas or extracts. The FDA doesn't regulate these over-the-counter treatments. This means that their dose and purity can vary from product to product. Their safety and effectiveness is not well understood.

    Medicines also are available to treat symptoms of excessive sleepiness if your insomnia is the result of shift work or alternating work schedules. You should discuss your situation with your doctor to determine whether these medicines, together with improving sleep habits, can help you overcome insomnia.


    Related category

       • HEALTH AND DISEASE