What is a home sleep apnea test, and what should you expect?

A home sleep apnea test is a simpler version of a sleep study that you do in your own bed. You wear a few sensors overnight that track your breathing and oxygen levels, and a sleep doctor reads the results. It's designed to confirm obstructive sleep apnea in people who are likely to have it, and it isn't the right test for everyone.

What does a home sleep apnea test measure?

The AASM's patient site, Sleep Education, says home test devices measure your breathing and blood oxygen level, and some also measure heart rate or other information. Cleveland Clinic describes a typical kit with four sensors, all connected to a recorder:

• A small prong in your nose to measure airflow
• A fingertip probe (a pulse oximeter) to measure oxygen
• A belt around your chest to measure breathing
• A belt around your abdomen to measure breathing

The test counts how often you have an apnea, where breathing stops for at least 10 seconds, or a hypopnea, where the airway is partly blocked. Those are combined into the apnea-hypopnea index (AHI), the number of events per hour. According to Cleveland Clinic, an AHI of five or above supports a sleep apnea diagnosis. Mild is in the 5 to 15 range, moderate is 15 to 30, and severe is above 30.

The AASM's clinical practice guideline, which is based on a systematic review of the research, makes a strong recommendation that either an in-lab sleep study or a home test with a technically adequate device be used to diagnose obstructive sleep apnea in uncomplicated adults who show signs of moderate to severe sleep apnea.

How is it different from an in-lab sleep study?

An in-lab sleep study, also called polysomnography, records much more. Sleep Education says it tracks your brain waves, heart rate and breathing as you sleep, along with eye, leg and arm movements and blood oxygen. You stay overnight at a sleep center, hospital or hotel room, and a technologist watches from a nearby room and can help if a sensor comes loose. It describes the in-lab study as giving the most complete evaluation of your sleep, and says it's usually recommended for more complex cases.

A home test uses simpler equipment you attach yourself, and it focuses on breathing and oxygen. Cleveland Clinic's Dr. Foldvary-Schaefer describes it as an abbreviated test with one purpose, which is to confirm sleep apnea. She says it isn't meant for more complicated sleep disorders and won't precisely measure how much sleep apnea you have.

Many people worry they won't sleep in a lab. Sleep Education says many patients don't sleep as well as at home, but that this typically doesn't affect the results, and that in most cases you don't need a full eight hours of sleep for a diagnosis.

Who is a home sleep apnea test for?

Sleep Education says a medical provider may recommend a home test when it's highly likely you have moderate to severe sleep apnea and you have no significant medical conditions apart from the suspected sleep apnea.

It says you shouldn't have a home test if:

• You don't have a high risk of sleep apnea
• Your doctor suspects a different sleep disorder
• You have certain conditions, including lung disease, neuromuscular disease or congestive heart failure
• It would be physically difficult for you to do the test at home

The AASM guideline also recommends an in-lab study rather than a home test for people with significant heart or lung disease, possible breathing muscle weakness from a neuromuscular condition, long-term opioid use, a history of stroke, or severe insomnia.

If you're wondering whether your snoring is worth testing at all, the main warning signs are snoring with choking, gasping or silent pauses in breathing, and daytime sleepiness. The AASM calls snoring paired with choking, gasping or pauses a reliable indicator of sleep apnea.

Sleep Education also lists the common risk factors. Excess weight is the major one, though slim people can have sleep apnea too. Others include a neck size of 17 inches or more for men or 16 inches or more for women, being male, and for women, reaching menopause. High blood pressure, a family history of sleep apnea, airway problems such as a deviated septum or nasal polyps, and alcohol or sedating medication also raise the risk.

Can an app, wearable or questionnaire diagnose sleep apnea?

An app, wearable or questionnaire can't diagnose sleep apnea. The AASM's diagnostic guideline makes a strong recommendation that clinical tools, questionnaires and prediction algorithms not be used to diagnose obstructive sleep apnea in adults without an in-lab sleep study or home sleep apnea test.

Consumer gadgets fall into the same gap. Sleep Education says other apps and sleep tracking devices may claim to detect sleep apnea, but their results can be unreliable, and it suggests discussing them with your medical provider. If a tracker flags something, treat that as a reason to book an appointment, not as a diagnosis either way.

How can you prepare for the appointment?

A little preparation makes the first conversation more useful. Sleep Education says your provider will want to know your symptoms and whether they started when you gained weight or stopped exercising. It suggests asking a partner, roommate or relative whether they've heard you snore loudly or make choking noises in your sleep.

It also recommends keeping a sleep diary for two weeks, noting what time you went to bed, when you woke up and how many times you woke in the night. That record can hold clues for the diagnosis, and it gives the doctor more to go on than memory.

How is a home sleep apnea test done?

Sleep Education describes the process like this. You may pick the equipment up from your doctor's office, or it may be delivered to your home. Someone from the sleep team will explain how to use it, so ask about anything that isn't clear.

On the day of the test, it suggests:

• Following your usual routine as much as possible
• Avoiding naps
• Cutting out alcohol and caffeine after lunch
• Telling your doctor about any regular medication, since they may ask you to pause it

You go to bed at your normal time and attach the sensors as instructed. You may be asked to keep a sleep log or press a button on the device when you get into bed. In the morning you take the sensors off. Depending on the device, you return it to the sleep center, mail it back, or throw it away if it's disposable.

Nancy Foldvary-Schaefer, DO, a sleep medicine specialist at Cleveland Clinic, describes it simply: turn it on, go to sleep, wake up, take it off and send it back. Its kits come with instructions and a phone number to call if you run into trouble.

If you normally use mouth tape or a nasal strip, ask the sleep team whether to wear it during the test. Our guide to whether mouth taping is safe explains why anyone with possible sleep apnea should see a doctor before taping.

How accurate is a home sleep apnea test?

A home sleep apnea test works well for its specific job, with some limits. Dr. Foldvary-Schaefer says home tests have a failure rate of around 7% or 8%, for reasons such as the device not working, not being turned on, or a sensor being placed wrongly. When that happens, she says the team decides whether to send the device back for another try or bring you in for a lab study. Dr. Foldvary-Schaefer also notes that home tests can underestimate how severe obstructive sleep apnea is.

Most failures are avoidable. Ask the sleep team to show you how each sensor goes on, keep the instructions and the support phone number by the bed, and check the device is switched on before you settle down. If you're asked to press a button when you get into bed or keep a sleep log, do both.

A negative result isn't the final word. Sleep Education says a negative home test isn't sophisticated enough to rule out sleep apnea, and the AASM guideline recommends an in-lab sleep study if a single home test is negative, inconclusive or technically inadequate. The guideline goes further for people whose symptoms still point to sleep apnea after a negative in-lab study, suggesting that a second study be considered.

So if your test comes back clear but you still snore loudly, stop breathing in your sleep according to your partner, or feel exhausted during the day, say so. Sleep Education describes that exact situation, a negative result with symptoms that still fit, as a reason for further testing.

What happens after the test, and how is sleep apnea treated?

The sleep team scores and interprets the recording, which Sleep Education says may take several days or weeks. A sleep doctor then contacts you to go over the results. If they're unclear, you may be asked to do an in-lab study.

If you're diagnosed with sleep apnea, the doctor will talk through treatment options and make a plan with you. The AASM says sleep apnea is typically treated with CPAP, and that alternatives include positional therapy, oral appliance therapy and surgery. Mouth tape and nasal strips are not treatments for sleep apnea.

Sleep Education describes the main options in more detail:

• CPAP uses a steady stream of air through a mask to keep the airway open, and it calls CPAP the frontline treatment recommended for most patients.
• An oral appliance, fitted by a dentist trained in dental sleep medicine, holds the tongue or jaw forward. It's recommended for mild to moderate sleep apnea in people who can't tolerate CPAP.
• Surgery can remove or reduce tissue that blocks the airway, and upper airway stimulation is an implanted device that moves the tongue forward during sleep.
• Positional therapy helps people whose sleep apnea happens mainly on their back.
• Weight loss may help if you're overweight, though it isn't guaranteed to resolve sleep apnea.

It also says quitting smoking and not drinking alcohol may improve symptoms. Untreated sleep apnea matters. Dr. Foldvary-Schaefer says people in the moderate to severe range have a higher risk of high blood pressure, heart disease, stroke and diabetes, so following through on treatment is worth it.

If your doctor has ruled out sleep apnea and you're still snoring, our guide on how to stop snoring is a good next read. If you share a room with someone whose snoring keeps you up, see sleeping next to a snorer.

Read next

• How to stop snoring
• Is mouth taping safe? Who should try it and who shouldn't

* This content is for informational and educational purposes only and is not medical advice. It is not intended to diagnose, treat, cure or prevent any disease or health condition. Talk to a qualified healthcare provider about your health.