Should I have a sleep study to diagnose obstructive sleep apnea?
This information will help you understand your choices, whether you share in the decision-making process or rely on your doctor’s recommendation.
Key points in making your decision
The most common form of sleep apnea is obstructive sleep apnea (OSA). Although doctors use sleep studies to diagnose both obstructive sleep apnea and central sleep apnea, this Decision Point focuses on obstructive sleep apnea.
Consider the following when making your decision:
- If you snore but do not have other symptoms of sleep apnea, you may not need a sleep study. Lifestyle changes, such as losing weight (if needed), sleeping on your side, and keeping a regular sleep schedule may reduce your snoring.
- If you have symptoms of sleep apnea (particularly excessive snoring or daytime sleepiness), your doctor will probably suggest a polysomnography sleep study. Polysomnography is the only sure way to find out whether you have sleep apnea.
- If you know that you have sleep apnea, you can treat it.
- If you have mild sleep apnea, or more severe sleep apnea without daytime sleepiness, treatment may or may not reduce your symptoms and complications such as high blood pressure.
- If you have moderate to severe sleep apnea, treatment generally reduces symptoms of sleep apnea and may reduce your risk of complications.
Medical Information
What is sleep apnea?
Sleep apnea occurs when you regularly stop breathing for 10 seconds or longer during sleep. It can be mild, moderate, or severe, depending on the number of times an hour that you stop breathing (apnea) or that airflow to your lungs is reduced (hypopnea). Apnea episodes may occur from 5 to 50 times an hour.
What causes obstructive sleep apnea?
A blockage or narrowing of the airways in your nose, mouth, or throat generally causes obstructive sleep apnea (OSA). This usually occurs when the throat muscles and tongue relax during sleep and partially or completely block the airway.
Sleep apnea can also occur if you have bone deformities or enlarged tissues in your nose, mouth, or throat. For example, you may have enlarged tonsils. During the day when you are awake and standing up, this may not cause problems. But when you lie down at night, the tonsils can press down on your airway, narrowing it and causing sleep apnea.
Other factors that make sleep apnea more likely include using certain medicines or alcohol before bed, sleeping on your back, and being obese.
Why should I have a sleep study?
A sleep study can give you a positive diagnosis of sleep apnea. This is important because if sleep apnea is not diagnosed and treated, it can interfere with your quality of life. If you have sleep apnea, you may be at risk for excessive daytime sleepiness and complications such as high blood pressure, high blood pressure in the lungs (pulmonary hypertension), depression, irregular heart rhythms, heart failure, coronary artery disease, and stroke.
Will treating sleep apnea help me?
Research shows that treating sleep apnea can reduce sleepiness. It may also improve blood pressure. For people with sleep apnea and coronary artery disease, treatment of sleep apnea can lower the risk of some problems such as heart failure.
Sleep apnea
The three main types of sleep apnea are:
Obstructive sleep apnea (OSA), which is the result of blocked airflow during sleep, such as from narrowed airways. Other factors, such as obesity, often contribute to obstructive sleep apnea.
Central sleep apnea, which results from a problem with how the brain signals the breathing muscles. This type of apnea can occur with conditions such as heart failure, brain tumors, brain infections, and stroke.
Mixed sleep apnea, which is a combination of obstructive and central sleep apnea.
A person who has sleep apnea may snore loudly and have restless sleep with difficulty breathing. The person may wake up with a headache and be very tired throughout the day.
Sleep apnea may improve with changes in sleep habits, such as not sleeping on your back. Sometimes devices to help breathing during sleep are useful, and occasionally surgery may help.
Continuous positive airway pressure (CPAP) therapy uses a machine to help a person who has obstructive sleep apnea (OSA) breathe more easily during sleep. A CPAP machine increases air pressure in the throat so your airway does not collapse when you breathe in. You use CPAP at home every night while you sleep.
- Continuous positive airway pressure (CPAP) for sleep apnea
Sleep studies can also determine whether you have a problem with your stages of sleep. The two stages of sleep are non-rapid eye movement (NREM) and rapid eye movement (REM). Normally, NREM and REM alternate 4 to 5 times during a night’s sleep. A change in this cycle may make it hard for you to sleep soundly.
Stages of sleep
Non-REM sleep
Non–rapid eye movement (non-REM) sleep has four stages:
- Stages 1 and 2 are light sleep in which breathing is slower than when a person is awake.
- Stages 3 and 4 are called slow-wave (delta) sleep, in which the person’s rate of breathing slows down further.
REM sleep
Rapid eye movement sleep is deeper than non-REM sleep. During REM sleep:
- The eyes and eyelids flutter.
- Breathing becomes irregular. During REM sleep, it is normal to have short episodes when breathing stops (apnea).
During sleep, a person usually progresses through the four stages of non-REM sleep before entering REM sleep. This takes about 60 to 90 minutes after falling asleep. The cycle is repeated three to four times each night with more time spent in the REM sleep stage and less time in sleep stages 3 and 4.
The most common sleep studies are:
- Polysomnogram. This test records several body functions during sleep, including brain activity, eye movement, oxygen and carbon dioxide blood levels, heart rate and rhythm, breathing rate and rhythm, the flow of air through your mouth and nose, snoring, body muscle movements, and chest and belly movement.
- Multiple sleep latency test (MSLT). This test measures how long it takes you to fall asleep. A video camera is used to record movements during sleep.
- Multiple wake test (MWT). This test measures whether you can stay awake during a time when you are normally awake.
Sleep studies usually are done in a sleep lab. Sleep labs are often located in hospitals.
MY SLEEP STUDY
Billings Clinic Sleep Center
I had a sleep study done at the Billings Clinic in Miles City, Montana last night. I haven’t yet met with my doctor to discuss the results of my sleep study however I asked the person who monitored my sleep at the sleep lab (Ed) and he stated that I woke up 80 times, approximately stopping breathing for 10 seconds each time, between the hours of 10:00 PM and 2:00 AM. At that point, he asked me to try sleeping with a CPAP (Continuous Positive Airway Pressure). I really do hope that a CPAP will give me the best sleep I have had in years, if ever. I have always snored loudly for as long as I can remember. I had a sleep study done 10 years ago and I woke up once every hour at that time and it wasn’t enough to determine whether it was actually sleep apnea and insurance wouldn’t cover the cost of a CPAP. I am really hopeful that this will give me more energy and a restful sleep. I will post more on on my sleep study after I have met with my doctor.
