In short
- Positional obstructive sleep apnea means your breathing events happen mostly when you sleep on your back. A common definition is a back-sleeping AHI at least twice the AHI in other positions.
- It's common. A 2017 meta-analysis estimates that body position affects apneas in roughly 56 to 75% of people with obstructive sleep apnea.
- Only a sleep study that records body position can show whether your sleep apnea is positional.
- Positional therapy uses a device to keep you off your back. Newer vibrating devices cut the AHI by about half in short-term studies.
- CPAP lowered the AHI more than positional therapy in a meta-analysis of head-to-head trials, so a sleep specialist should decide whether positional therapy is enough on its own.
Positional sleep apnea is obstructive sleep apnea that happens mostly, or only, when you sleep on your back. It's common, and for some people keeping off their back with a positional therapy device can reduce breathing events a lot. A sleep study is the only way to know whether your sleep apnea is positional, and a sleep specialist should decide whether positional therapy is enough on its own.
What is positional sleep apnea?
In obstructive sleep apnea, the upper airway narrows or closes repeatedly during sleep. In positional obstructive sleep apnea (often shortened to POSA), body position makes a big difference to how often that happens. The NHS lists sleeping on your back among the factors linked to sleep apnea.
Researchers use a simple rule to define it. In a 2025 study in the Journal of Clinical Sleep Medicine, people with sleep apnea were classed as positional if their apnea-hypopnea index (AHI) on their back was at least twice their AHI in other positions. The AHI is the number of breathing pauses and shallow breaths per hour of sleep.
Some people have breathing problems almost entirely on their back and very few on their side. Others are worse on their back but still have significant events in other positions. The 2025 study described both groups.
How common is it?
Research: moderate (what this means)Positional sleep apnea is more common than many people expect. A 2017 meta-analysis in the Journal of Clinical Sleep Medicine says body position influences how often and how long apneas happen in roughly 56 to 75% of people with obstructive sleep apnea.
The 2025 study looked at a community sample rather than sleep clinic patients. Among 1,870 participants in the US Sleep Heart Health Study, 62% of those with sleep apnea met the positional definition and 38% did not. Compared with the non-positional group, people with positional sleep apnea were slightly older and less obese, and they had higher systolic blood pressure. Their overall AHI was also higher, as was their AHI on their back.
Within the positional group, the researchers separated people whose apnea was worse on their back from those whose apnea occurred only on their back. The "worse on the back" group was larger and had more fragmented sleep, higher AHI and more high blood pressure and diabetes. So positional doesn't automatically mean mild.
How do you find out if yours is positional?
A sleep study can show whether your sleep apnea is positional. In the 2025 study, positional status was worked out from the AHI on the back versus the AHI in other positions, which means the test has to record your body position alongside your breathing. Ask your sleep doctor how your events were spread across positions and how much of the night you spent on your back.
If you haven't had a sleep test yet, start there. Our guide to the home sleep apnea test explains the process, and snoring vs. sleep apnea covers the warning signs. If you've been tracking your snoring with an app, snoring apps and sleep trackers explains what those tools can and can't tell you.
What is positional therapy?
Sleep Education, the AASM's patient site, describes positional therapy as a behavioral treatment for sleep apnea. If your breathing is interrupted mainly when you're on your back and is normal on your side or stomach, your sleep doctor might recommend it.
The aim is to keep you off your back. Sleep Education describes a few approaches:
- Devices worn around the waist or back that make it hard to turn over
- A backpack or tennis ball that makes back sleeping uncomfortable
- Newer devices worn on the neck or chest that vibrate gently when you start to roll onto your back
The vibrating devices are designed to nudge you into changing position without waking you, and some increase the vibration if you stay on your back. Some also record data your sleep doctor can use, such as how often you change position. The NHS suggests similar low-tech options for people with diagnosed sleep apnea, such as a tennis ball taped to the back of your sleepwear or a special pillow or bed wedge. The NHLBI says a provider may recommend side sleeping because it can help keep the airway open. For general tips on sleeping positions, see the best sleep position for breathing and sleep position and snoring.
How well does positional therapy work?
Positional therapy works well in the short term, and the newer devices show clear benefits. The 2017 meta-analysis pooled three cohort studies and four randomized trials of vibrating devices. On average, the AHI fell by 11.3 events an hour, a 54% reduction, and time spent on the back fell by 84%. The authors called the evidence strong for short-term reductions in AHI, and described the devices as simple to use for both patients and clinicians, and reversible.
But the same authors said long-term adherence couldn't be assessed for lack of reliable data, and called for longer, high-quality studies. A 2020 review in Sleep Medicine Clinics notes that the AASM has treated positional therapy as only an alternative therapy, because older methods had poor tolerance and adherence, while newer devices have renewed interest.
How does it compare with CPAP and oral appliances?
Positional therapy generally falls short of CPAP, which still comes out ahead on average. A 2014 meta-analysis of three crossover trials, with 71 people with positional sleep apnea, found that positional therapy left a higher AHI and lower oxygen levels than CPAP. The authors concluded CPAP was superior at reducing sleep apnea severity.
Oral appliances are another comparison point. A 2024 meta-analysis of randomized trials found both positional therapy and oral appliance therapy improved positional sleep apnea, with no significant difference in total AHI or adherence. There was also no significant difference in the oxygen desaturation index, sleep efficiency or the number of arousals. Oral appliances did better on AHI in other positions and on sleepiness scores, while positional therapy kept people off their backs more.
Sleep Education says positional therapy can be used alone or together with another treatment. Your sleep specialist will weigh how severe your sleep apnea is, how much of it is positional and which option you'll actually use. Our overview of sleep apnea treatment options explains the alternatives.
Do mouth tape or nasal strips help?
No, mouth tape and nasal strips don't treat sleep apnea, positional or otherwise. Don't use them as a substitute for a sleep study or for treatment your doctor recommends. Our safety page explains when mouth tape isn't appropriate.
This article is general information, not medical advice. Talk to a doctor or sleep specialist about your own results.
Read next
Common questions
What is positional sleep apnea?
It's obstructive sleep apnea where most breathing events happen while you lie on your back. Researchers commonly define it as an apnea-hypopnea index on your back that is at least twice as high as in other positions.
Can you have sleep apnea while sleeping on your side?
Yes. In a 2025 community study, 38% of people with sleep apnea didn't meet the positional definition, so their breathing events weren't concentrated on their back, and many people whose apnea was worse on their back still had events in other positions. Side sleeping helps some people a lot, but only a sleep study that records body position can show how much it helps you.
What is the difference between sleep apnea and obstructive sleep apnea?
Obstructive sleep apnea is the most familiar type of sleep apnea rather than a separate condition. The NHLBI explains that obstructive sleep apnea is caused by something blocking airflow through the upper airway during sleep, such as the tongue falling backward, while central sleep apnea comes from problems with how the brain controls breathing. Positional sleep apnea is a form of obstructive sleep apnea.
How do I know if my sleep apnea is positional?
Your sleep study report can show it, because it records your body position along with your breathing. Ask your sleep doctor whether your events were mainly on your back.
Does sleeping on your side help sleep apnea?
For some people, yes. The NHLBI says a provider may recommend side sleeping because it can help keep the airway open, and the NHS suggests side sleeping for people with diagnosed sleep apnea. How much it helps depends on whether your sleep apnea is positional.
Is positional therapy as good as CPAP?
Not on average. A meta-analysis of three crossover trials in people with positional sleep apnea found CPAP lowered the AHI more and kept oxygen levels higher than positional therapy.
What devices are used for positional therapy?
Sleep Education describes belts or backpack-style devices that make back sleeping uncomfortable, a tennis ball that makes lying on your back uncomfortable, and newer devices worn on the neck or chest that vibrate gently when you roll onto your back.
Do people stick with positional therapy?
A 2020 review says older positional methods had poor tolerance and adherence. Newer vibrating devices show better adherence in short-term studies, but a 2017 meta-analysis says long-term adherence couldn't be judged because of a lack of reliable data.
Sources
- Positional therapy
- Community prevalence of positional obstructive sleep apnea
- Efficacy of the new generation of devices for positional therapy for patients with positional obstructive sleep apnea: a systematic review of the literature and meta-analysis
- Comparison of positional therapy versus continuous positive airway pressure in patients with positional obstructive sleep apnea: a meta-analysis of randomized trials
- Oral appliance therapy vs. positional therapy for managing positional obstructive sleep apnea; a systematic review and meta-analysis of randomized control trials
- Positional therapy for positional obstructive sleep apnea
- Sleep apnoea
- Sleep apnea: causes and risk factors
- Sleep apnea: treatment
About this article
- Research
- 9 published sources, listed above.
- Evidence
- Moderate. How we rate it
- Last checked
- October 10, 2026
- Funding
- Paid partner of Titan Recovery. Their ads are labeled.
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* 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.
