How to Prepare for a Sleep Apnea Test

Obstructive sleep apnea is an obstruction in your upper airway that stops normal breathing for a brief time while you’re sleeping. In some people, this can occur hundreds of times each night.

Obstructive sleep apnea is often associated with snoring, but not all snoring indicates that you have sleep apnea, and not everyone with sleep apnea snores — although most do. Other symptoms of sleep apnea include daytime fatigue, morning headaches and urinating more at night.

Traditionally, doctors have associated sleep apnea with overweight, middle-aged men. However, anyone can have sleep apnea, including children. Genetics also plays a role.

There’s also a type of sleep apnea called central sleep apnea, which occurs when the brain doesn’t signal properly to the respiratory system when it should breathe. Obstructive sleep apnea is the most common type of sleep apnea.

About 30 million adults in the U.S. have obstructive sleep apnea, but about 23.5 million of them are undiagnosed, according to the American Academy of Sleep Medicine.

[Read: Sleep Reset 2021: Getting Your Sleep Back to Normal.]

Risks of Sleep Apnea

It’s important to get evaluated for sleep apnea if you or your partner thinks that you have it because, untreated, it can raise your chance for serious chronic conditions and health events, including:

— A heart attack.

— Car crashes if you’re groggy and fall asleep while driving.


High blood pressure.


Type 2 diabetes.

Obstructive sleep apnea also can affect your quality of life, leaving you unmotivated or cranky about what you have to get done during the day.

Getting diagnosed and treated for sleep apnea also is important because of the work your body does while sleeping. This includes repairing muscles, releasing certain hormones and consolidating memories. Interruption of sleep can affect the vital work your body does each night.

[READ: Does Melatonin Work for Sleep?]

Getting Tested for Sleep Apnea

A sleep study, also called a sleep test or polysomnography, is what doctors use to diagnose sleep apnea. Doctors can order a sleep study that you do at home for a night or two or a test that you complete at a sleep lab for one night. Each type of sleep study has its pros and cons.

At-Home Sleep Study
Here are a few pros and cons of an at-home sleep study:

— You can do the test from the convenience of your own home.

— Insurance is usually more likely to cover a home test as it’s less expensive.

— There’s minimal equipment that you have to wear compared to an in-lab study.

— An at-home sleep study can only diagnose sleep apnea but not other sleep disorders.

— An at-home study may underdiagnose sleep apnea, leading a health provider to recommend a follow-up study in a sleep lab.

In-Lab Sleep Study
Here are some advantages and drawbacks of an in-lab sleep study:

— You must travel to a sleep lab in your area to complete the test.

— The in-lab study can diagnose other sleep disorders, such as nighttime seizures or limb movements while dreaming, says Dr. Indira Gurubhagavatula, chair of the American Academy of Sleep Medicine COVID-19 Task Force and associate professor of medicine at the University of Pennsylvania in Philadelphia.

— The results from an in-lab sleep study are more accurate, adds Dr. Karen L. Lee, clinical assistant professor of neurology at NYU Langone Health’s Epilepsy SLEEP Lab in New York City.

— Insurance may not cover an in-lab sleep study.

Sleep studies collect several types of information to determine if you have sleep apnea. The information gathered may vary slightly based on the type of test but often includes:

— Body movements.

— Breathing patterns.

— Your heart rate.

— Your oxygen level.

[READ: Sleep Disorders and Chronic Pain.]

Preparing for a Sleep Study

There are a few ways you can prepare to ensure you get the most accurate results from your sleep study.

1. Watch your caffeine intake on the day of your sleep study.
It’s OK to drink coffee or other caffeinated beverages in the morning for most people, but steer clear in the afternoon and evening. That’s because caffeine can keep you awake, and health providers want you to come to the lab hungry for sleep, Gurubhagavatula says. Make sure to consider other foods or drinks with hidden caffeine, such as chocolate.

2. Don’t take naps the day of your sleep study.

3. Try to avoid alcohol.
This can negatively affect your sleep and make sleep apnea worse.

4. If you’re doing the test at a sleep lab, make sure to bring:

— Your pajamas.

— A favorite pillow (if you have one) or anything else that helps you sleep better. “We want you to be as relaxed and as comfortable as you can,” says Dr. Fariha Abbasi-Feinberg, board member with the American Academy of Sleep Medicine and practicing sleep medicine physician with Millennium Physician Group in Fort Myers, Florida.

— Any toiletry items you’ll need for the evening or the next morning.

— Any medications that you typically use at night, but review those medications in advance with the provider who ordered the test.

The doctor who ordered the test should give you a list of any other items to bring with you to an in-lab sleep study.

5. Choose a day when you can aim for a good night’s sleep.
If there’s a baby who usually sleeps in your room and wakes you up, plan to do your in-home test on a night when the baby can sleep elsewhere, Gurubhagavatula says. The same applies if you have a partner, teens or adult children who come home late on certain nights, causing you to wake up more.

6. Review in advance any instructions that come with the equipment for an at-home test.
The equipment usually will arrive in the mail, and written instructions will explain how to wear the equipment. The equipment may seem cumbersome at first. Typically, you mail back the equipment when finished.

7. Talk to your doctor in advance if you have insomnia.
They may recommend avoiding sleep the night before so you’re more likely to sleep on the night of the test, Lee says.

What to Expect During a Sleep Study

Here’s what to expect during an in-lab sleep study:

— You’ll arrive in the evening, and a technician will have you sign some paperwork.

— You’ll be shown to a room that is similar to a hotel room and will likely have a TV and a fan as well as a private bathroom.

— Once you’re ready for bed, the technician will spend 30 minutes or more attaching various electrodes to your body, including to your scalp, chest and legs. The electrodes don’t hurt. All of these electrodes provide information to evaluate when you’re actually asleep, how well you have slept and whether or not you have sleep apnea.

— Try to fall asleep at your normal time. While you sleep, the technician can monitor the feedback from the electrodes and a video recording of you sleeping. This camera is set up to turn on when the room is dark.

— Your doctor’s office or the sleep lab will find out in advance if you need to be up by a certain time. They will help ensure that you wake up on time. Otherwise, they will let you sleep until 8 a.m. or so. (If you work at night, some labs may be able to accommodate a sleep study during the day.)

— You can get ready in the morning at the lab or go home to get ready.

Here’s what to expect during an at-home sleep study:

— Follow any instructions given to you by your provider on how to wear the equipment. Although there are a few types of at-home sleep studies, the equipment will often include a belt around your chest and a nasal cannula to measure breathing patterns, and an oximeter you wear on a finger to track your heart rate and oxygen. Newer tests may require only a device worn on your finger, Abbasi-Feinberg says.

— Use anything you would typically use to help you sleep better, such as a white noise machine or aromatherapy like essential oils. The goal is to get a good night’s sleep.

— Sometimes, a part of the equipment will fall off at night. It’s better that the equipment stays on like it should, but providers usually can still interpret the results. If equipment that has fallen off makes it harder to read the results, they may ask you to come in person for a lab test.

With the equipment used during a sleep study, you may wonder how much sleep you’ll actually get. It may not be the most relaxing sleep of your life, but most tests provide enough data for health providers to analyze. Some people are so tired that they sleep even with the distraction of the equipment, Gurubhagavatula says. Providers need a minimum of two hours of sleep data to evaluate for sleep apnea, Lee says.

Discussing the Sleep Study Results

After your sleep study, your provider will review the results. Some may have you return to their office to go over the results. Others may call you to discuss them. It can be overwhelming to see all of the numbers from a sleep study without any explanation, Gurubhagavatula says. This is why providers typically will go over the results with you or provide a written summary.

Providers interpreting sleep study findings will use the Apnea-Hypopnea Index to measure if you have sleep apnea.

An apnea is a complete closure of the airway you use to breathe, and a hypopnea is a partial closure. Five or move apnea/hypopnea incidents in an hour indicates that you have sleep apnea. Sleep apnea is measured as mild, moderate or severe.

With mild sleep apnea, your provider may just monitor you over time. For moderate or severe sleep apnea, treatment options include a continuous positive airway pressure (CPAP) machine, an oral appliance or certain types of surgery. If you’re actively trying to lose weight and you have moderate sleep apnea, weight loss may be enough to help for some people, Abbasi-Feinberg says.


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