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Feature:
Sleep Disorders

Diagnosing Sleep Disorders

Depending on your symptoms, it may help you to gather information on your sleep behaviors. Your healthcare provider will review this information and consider several possible tests when trying to diagnose a sleep disorder:

Sleep history and sleep log

If you believe you have a sleep problem, consider keeping a sleep diary and bringing it to your next medical appointment. Your physician will ask you how many hours you sleep each night, how often you awaken during the night and for how long, how long it takes you to fall asleep, how well rested you feel upon awakening, and how sleepy you feel during the day. If you don't already keep a sleep diary, your health professional may ask you to keep one for a few weeks. Your provider also may ask you whether you have any symptoms of a sleep disorder, such as loud snoring, snorting or gasping, morning headaches, tingling or unpleasant sensations in the limbs that are relieved by moving them, and jerking of the limbs during sleep. You may want to ask your sleeping partner if you have these symptoms, since you may not be aware of them yourself.

Sleep recording in a sleep laboratory

A sleep recording or polysomnogram (PSG) may be done while you stay overnight at a sleep center or at home. Your doctor will suggest the appropriate location for the PSG based on your symptoms and health. Electrodes and other monitors are placed on your scalp, face, chest, limbs, and finger. While you sleep, these devices measure your brain activity, eye movements, muscle activity, heart rate and rhythm, blood pressure, and how much air moves in and out of your lungs. This test also checks the amount of oxygen in your blood. A PSG test is painless. In certain circumstances, the PSG can be done at home. A home monitor can be used to record heart rate, how air moves in and out of your lungs, the amount of oxygen in your blood, and your breathing effort.

Multiple sleep latency test (MSLT)

This daytime sleep study measures how sleepy you are and is particularly useful for diagnosing problems staying awake during the day. The MSLT is conducted in a sleep laboratory and typically done after an overnight sleep recording (PSG). In this test, monitoring devices for sleep stage are placed on your scalp and face. You are asked to nap four or five times for 20 minutes every two hours during the day. Technicians note how quickly you fall asleep and how long it takes you to reach various stages of sleep, especially REM (rapid eye movement) sleep, during your naps. Normal individuals either do not fall asleep during these short designated naptimes or take a long time to fall asleep. People who fall asleep in less than five minutes are likely to require treatment for a sleep disorder, as are those who quickly reach REM sleep during their naps.

The Importance of Sleep

Many people view sleep as merely a "down time," when their brains shut off and their bodies rest. People may cut back on sleep, because other responsibilities seem much more important. But research shows that a number of vital tasks carried out during sleep help people stay healthy and function at their best.

While you sleep, your brain is hard at work forming the pathways necessary for learning and creating memories and new insights. Without enough sleep, you can't focus and pay attention or respond quickly. A lack of sleep may even cause mood problems. Growing evidence shows that a chronic lack of sleep can also increase your risk of obesity, diabetes, cardiovascular disease, and infections.

The nonstop "24/7" nature of the world today encourages longer or nighttime work hours and offers continual access to entertainment and other activities. To keep up, people cut back on sleep. A common myth is that people can learn to get by on little sleep (such as less than six hours a night) with no negative effects. Research suggests, however, that adults need at least seven to eight hours of sleep each night to be well rested.

Evidence from other national surveys indicate that 70 percent of adolescents sleep less than the recommended 8 to 9 hours each night. Lack of sleep may have a direct effect on children's health, behavior, and development.

Read More "Sleep Disorders" Articles

Are You Sleep Deprived? / Diagnosing Sleep Disorders / Tips for Getting A Good Night's Sleep / Advances In Sleep Studies

Summer 2015 Issue: Volume 10 Number 2 Page 21