How is sleep apnea diagnosed?

The diagnosis of sleep apnea starts with an examination by your doctor, who will take a history and perform a physical examination. Of course that means you have to go to your doctor and tell him your symptoms. He may ask you to fill out a questionnaire about your sleep and breathing that will identify risk factors for sleep apnea. This is all stuff that takes place while you are awake, so if sleep apnea is suspected, then obviously you must be examined while you are asleep. That examination can take place in your home unless a sleep disorder other than sleep apnea is suspected, or there are reasons that a technician must be with you during the test. If that is the case then the examination will probably be done in a sleep laboratory. The laboratory study typically involves having a variety of sensors placed on you by a technician, so that brain waves, eye movements and muscle activity can be recorded. This allows the determination of sleep and sleep stages by the classic methodology. Both home testing and laboratory testing usually involve the recording of snoring, body or head position, movement, airflow at the airway opening, effort to breathe, pulse or heart rate and blood oxygen levels by an oximeter (a non-invasive device that is worn on the finger, ear or forehead). Some home testing devices also can record brain waves for an estimation of sleep time.

The information stored on the home or laboratory recorder can be reviewed by a specialist in sleep medicine, and a determination made if you have sleep apnea or not, the kind of sleep apnea you have (there are two major types, obstructive and central and they can occur together), and how severe the problem is in terms of the frequency of abnormal breathing events overall and by sleeping position. The amount of time you spend with low oxygen levels will also be determined. A report of those findings is then sent to your doctor who ordered the study. The diagnostic sleep study is perfectly safe, and when done in your own bed, reasonably comfortable.

Sleep apnea is diagnosed with a sleep study either in a sleep laboratory or at home, depending on the patient’s needs. In the sleep lab, patients will come in at bedtime and spend the night in the sleep lab. During the night patients have 27 electrodes attached to them (no needles, just paste and tape), along with other sensors. The sleep study monitors breathing, heart rate and rhythms, leg movement, muscle movement, brain waves, oxygen saturation and snoring to look for a series of patterns which can identify certain sleep disorders. There are also home sleep testing monitors which can be set up in the home, by the patient, and then returned to the doctor or mailed to a company where the data that is collected can be interpreted and analyzed.

If your healthcare provider suspects you may have sleep apnea - a serious sleep disorder in which breathing is interrupted throughout the night – he or she may refer you to a sleep medicine specialist. This specially trained professional will ask you questions about your medical history, perform a physical examination, and may conduct a sleep test (called a polysomnogram).

Usually sleep tests are conducted in a hospital sleep laboratory. This means you stay overnight in the hospital hooked up to machines while you sleep. The machines measure your breathing effort and airflow, blood oxygen level, heart rate and rhythm, duration of the various stages of sleep, body position, and movement of your arms and legs. Home-monitoring devices are also available if the specialist decides they are appropriate for you.

Being checked for sleep apnea if you have symptoms is important to your cardiovascular health. Sleep apnea can contribute to serious cardiovascular problems, including heart attack and stroke.

Sleep apnea is usually diagnosed through formal sleep studies in an outpatient setting. A sleep study, or polysomnography, monitors patients' breathing while they sleep through a full night.

Most studies are done over two separate visits, the first during which the patient sleeps and oxygenation and breathing patterns are recorded. If the patient has significant symptoms of sleep apnea, then he may need a follow-up evaluation with a positive airway device that provides air through a fitted mask. Occasionally the study may be done in one night, with the first part of the night the initial evaluation and the second part of the night with the positive airway device.

In some cases, if the patient does not have recorded apneic episodes but there is a high suspicion that the patient has obstructive sleep apnea, then the test may be repeated.

Signs and symptoms of obstructive sleep apnea include but are not limited to choking awake, dry mouth or sore throat, moodiness, extreme fatigue and daytime sleepiness, decreased concentration, chest pain, depression, hypertension and other physical symptoms. If you think you may have sleep apnea, one of the first steps is to speak with your doctor.