Table of ContentsView AllTable of ContentsWhat Is Sleep Apnea?Oxygen LevelsSymptomsRisk FactorsDiagnsosisOther CausesTreatment
Table of ContentsView All
View All
Table of Contents
What Is Sleep Apnea?
Oxygen Levels
Symptoms
Risk Factors
Diagnsosis
Other Causes
Treatment
People withobstructive sleep apnea (OSA)typically have low oxygen levels when they sleep because of gaps in their breathing. Blood oxygen during sleep is considered low if levels are below 95%. Medical intervention may be advised if it drops below 92%.
Low blood oxygen places you at risk ofhypoxemiain which tissues are deprived of the oxygen they need to function, causing fatigue, lightheadedness, and shortness of breath. Over time, OSA-associated hypoxia can increase the risk of stroke andbrain aneurysmand even affect yourcognitive function.
This article explains what sleep apnea is and its impact on blood oxygen levels. It also describes the causes, symptoms, and diagnosis of obstructive sleep apnea and explores other possible causes of low blood oxygen levels during sleep.
Photomick / Getty Images
What Is Obstructive Sleep Apnea?
Obstructive sleep apnea is one of two mainforms of sleep apneain which your throat muscles relax, blocking the passage of air into yourtrachea(windpipe) while sleeping. When this happens, breathing can stop for anywhere from a few seconds to over a minute in some people.
People with OSA have frequent, repeated gaps in breathing, with some experiencing more than a hundred per night.While the person with OSA may be unaware of these gaps, their sleep partner often is.
According to the National Council on Aging, around 39 million adults in the United States have sleep apnea, of whom 33 million useCPAP machinesto help normalize their breathing at night.
What Is Central Sleep Apnea?
Sleep Apnea and Normal Blood Oxygen Levels
Obstructive sleep apnea can affect your blood oxygen levels due to the inadequate intake of air while sleeping.
During the day, blood oxygen levels—also known asoxygen saturation levels—generally fall between 95% and 100% in healthy people, whether asleep or awake. This is considered normal.
However, prolonged or repeated gaps in breathing while asleep can cause oxygen levels to drop to where tissues and organs are adversely affected. This is referred to as sleep-related hypoxemia.
Oxygen saturation levels of 92% or below generally require medical intervention. This is the level often seen in someone withCOPDwho is onoxygen therapy.
The interpretation of oxygen saturation levels can be described as follows:
Symptoms of Sleep Apnea
If sleep-related hypoxemia occurs, you may also experience more profound and problematic symptoms like:
What Is “Mild” Obstructive Sleep Apnea?
Risk Factors for Obstructive Sleep Apnea
People of any age, sex, or weight can have obstructive sleep apnea, but it is much more common in males, people over the age of 50, and those diagnosed withobesity.
Other risk factors for OSA include:
Diagnosis
Obstructive sleep apnea is diagnosed with anovernight sleep study, also known as apolysomnogram. This is a test conducted in a specialized facility that records multiple body symptoms while you sleep. This includes checking your blood oxygen levels.
Components of an overnight sleep study include:
Other Causes of Low Blood Oxygen During Sleep
Obstructive sleep apnea is the most common—but not only—explanation of low oxygen saturation levels during sleep. Some other possible causes fall under three broad categories:
Treating Sleep Apnea
In general, the first-line treatment iscontinuous positive air pressure (CPAP) therapy. This involves wearing a device that delivers pressurized room air through a mask to keep your airways open at night.
In addition to CPAP, your healthcare provider may recommend:
If these conservative options fail, there are surgeries that can reduce airway obstruction or better direct airflow from the nose and mouth to the trachea, including:
Treating OSA will increase blood oxygen levels while sleeping. Left untreated, OSA can increase the risk of high blood pressure,coronary artery disease (CAD),atrial fibrillation, andtype 2 diabetes. This is why treating OSA is so important, especially when it is moderate to severe.
How Sleep Apnea Is Treated
Summary
Obstructive sleep apnea (OSA) is a sleep disorder caused when throat muscles relax and interfere with breathing. Frequent and prolonged gaps can reduce the level of oxygen in the bloodstream.
Untreated OSA can lead to serious health problems, including an increased risk of high blood pressure, heart disease, and diabetes. This is why it is important to get diagnosed if you have symptoms and risk factors of OSA.
OSA is typically diagnosed with an overnight sleep study that, among other things, measures your blood oxygen with a pulse oximeter. Depending on the results of these and other tests, a doctor can decide which treatment options are best for you.
Does Sleep Apnea Ever Go Away?
14 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.MedlinePlus.Pulse oximetry.Jung TY, Lee E, Park M, et al.Obstructive sleep apnea and its influence on intracranial aneurysm.J Clin Med.2024 Jan;13(1):144. doi:10.3390/jcm13010144Franklin KA, Lindberg E.Obstructive sleep apnea is a common disorder in the population-a review on the epidemiology of sleep apnea.J Thorac Dis. 2015;7(8):1311–1322. doi:10.3978/j.issn.2072-1439.2015.06.11Spicuzza L, Caruso D, Di Maria G.Obstructive sleep apnea syndrome and its management.Ther Adv Chronic Dis. 2015;6(5):273-285. doi:10.1177/2040622315590318National Council on Aging.Sleep apnea statistics and facts you should know.American Thoracic Society.Pulse oximetry.Pilcher J, Beasley R.Acute use of oxygen therapy.Aust Prescr.2015 Jun;38(3):98–100. doi:10.18773/austprescr.2015.033Abbasi A, Gupta SS, Sabharwal N, et al.A comprehensive review of obstructive sleep apnea.Sleep Sci.2021;14(2):142-154. doi:10.5935/1984-0063.20200056Perger E, Baillieu S, Esteve F, et al.Nocturnal hypoxemia, blood pressure, vascular status and chronic mountain sickness in the highest city in the world.Ann Med.2022;54(1):1884–1893. doi:10.1080/07853890.2022.2091791American Sleep Association.Sleep study test results.Böing S, Randerath WJ.Chronic hypoventilation syndromes and sleep-related hypoventilation.J Thorac Dis2015;7(8). doi:10.3978/j.issn.2072-1439.2015.06.10MedlinePlus.Breathing difficulty.Sarkar M, Niranjan N, Banyal PK.Mechanisms of hypoxemia.Lung India. 2017;34(1):47-60. doi:10.4103/0970-2113.197116Surani SR.Diabetes, sleep apnea, obesity and cardiovascular disease: Why not address them together?World J Diabetes.2014 Jun 15;5(3):381–4. doi:10.4239/wjd.v5.i3.381
14 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.MedlinePlus.Pulse oximetry.Jung TY, Lee E, Park M, et al.Obstructive sleep apnea and its influence on intracranial aneurysm.J Clin Med.2024 Jan;13(1):144. doi:10.3390/jcm13010144Franklin KA, Lindberg E.Obstructive sleep apnea is a common disorder in the population-a review on the epidemiology of sleep apnea.J Thorac Dis. 2015;7(8):1311–1322. doi:10.3978/j.issn.2072-1439.2015.06.11Spicuzza L, Caruso D, Di Maria G.Obstructive sleep apnea syndrome and its management.Ther Adv Chronic Dis. 2015;6(5):273-285. doi:10.1177/2040622315590318National Council on Aging.Sleep apnea statistics and facts you should know.American Thoracic Society.Pulse oximetry.Pilcher J, Beasley R.Acute use of oxygen therapy.Aust Prescr.2015 Jun;38(3):98–100. doi:10.18773/austprescr.2015.033Abbasi A, Gupta SS, Sabharwal N, et al.A comprehensive review of obstructive sleep apnea.Sleep Sci.2021;14(2):142-154. doi:10.5935/1984-0063.20200056Perger E, Baillieu S, Esteve F, et al.Nocturnal hypoxemia, blood pressure, vascular status and chronic mountain sickness in the highest city in the world.Ann Med.2022;54(1):1884–1893. doi:10.1080/07853890.2022.2091791American Sleep Association.Sleep study test results.Böing S, Randerath WJ.Chronic hypoventilation syndromes and sleep-related hypoventilation.J Thorac Dis2015;7(8). doi:10.3978/j.issn.2072-1439.2015.06.10MedlinePlus.Breathing difficulty.Sarkar M, Niranjan N, Banyal PK.Mechanisms of hypoxemia.Lung India. 2017;34(1):47-60. doi:10.4103/0970-2113.197116Surani SR.Diabetes, sleep apnea, obesity and cardiovascular disease: Why not address them together?World J Diabetes.2014 Jun 15;5(3):381–4. doi:10.4239/wjd.v5.i3.381
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
MedlinePlus.Pulse oximetry.Jung TY, Lee E, Park M, et al.Obstructive sleep apnea and its influence on intracranial aneurysm.J Clin Med.2024 Jan;13(1):144. doi:10.3390/jcm13010144Franklin KA, Lindberg E.Obstructive sleep apnea is a common disorder in the population-a review on the epidemiology of sleep apnea.J Thorac Dis. 2015;7(8):1311–1322. doi:10.3978/j.issn.2072-1439.2015.06.11Spicuzza L, Caruso D, Di Maria G.Obstructive sleep apnea syndrome and its management.Ther Adv Chronic Dis. 2015;6(5):273-285. doi:10.1177/2040622315590318National Council on Aging.Sleep apnea statistics and facts you should know.American Thoracic Society.Pulse oximetry.Pilcher J, Beasley R.Acute use of oxygen therapy.Aust Prescr.2015 Jun;38(3):98–100. doi:10.18773/austprescr.2015.033Abbasi A, Gupta SS, Sabharwal N, et al.A comprehensive review of obstructive sleep apnea.Sleep Sci.2021;14(2):142-154. doi:10.5935/1984-0063.20200056Perger E, Baillieu S, Esteve F, et al.Nocturnal hypoxemia, blood pressure, vascular status and chronic mountain sickness in the highest city in the world.Ann Med.2022;54(1):1884–1893. doi:10.1080/07853890.2022.2091791American Sleep Association.Sleep study test results.Böing S, Randerath WJ.Chronic hypoventilation syndromes and sleep-related hypoventilation.J Thorac Dis2015;7(8). doi:10.3978/j.issn.2072-1439.2015.06.10MedlinePlus.Breathing difficulty.Sarkar M, Niranjan N, Banyal PK.Mechanisms of hypoxemia.Lung India. 2017;34(1):47-60. doi:10.4103/0970-2113.197116Surani SR.Diabetes, sleep apnea, obesity and cardiovascular disease: Why not address them together?World J Diabetes.2014 Jun 15;5(3):381–4. doi:10.4239/wjd.v5.i3.381
MedlinePlus.Pulse oximetry.
Jung TY, Lee E, Park M, et al.Obstructive sleep apnea and its influence on intracranial aneurysm.J Clin Med.2024 Jan;13(1):144. doi:10.3390/jcm13010144
Franklin KA, Lindberg E.Obstructive sleep apnea is a common disorder in the population-a review on the epidemiology of sleep apnea.J Thorac Dis. 2015;7(8):1311–1322. doi:10.3978/j.issn.2072-1439.2015.06.11
Spicuzza L, Caruso D, Di Maria G.Obstructive sleep apnea syndrome and its management.Ther Adv Chronic Dis. 2015;6(5):273-285. doi:10.1177/2040622315590318
National Council on Aging.Sleep apnea statistics and facts you should know.
American Thoracic Society.Pulse oximetry.
Pilcher J, Beasley R.Acute use of oxygen therapy.Aust Prescr.2015 Jun;38(3):98–100. doi:10.18773/austprescr.2015.033
Abbasi A, Gupta SS, Sabharwal N, et al.A comprehensive review of obstructive sleep apnea.Sleep Sci.2021;14(2):142-154. doi:10.5935/1984-0063.20200056
Perger E, Baillieu S, Esteve F, et al.Nocturnal hypoxemia, blood pressure, vascular status and chronic mountain sickness in the highest city in the world.Ann Med.2022;54(1):1884–1893. doi:10.1080/07853890.2022.2091791
American Sleep Association.Sleep study test results.
Böing S, Randerath WJ.Chronic hypoventilation syndromes and sleep-related hypoventilation.J Thorac Dis2015;7(8). doi:10.3978/j.issn.2072-1439.2015.06.10
MedlinePlus.Breathing difficulty.
Sarkar M, Niranjan N, Banyal PK.Mechanisms of hypoxemia.Lung India. 2017;34(1):47-60. doi:10.4103/0970-2113.197116
Surani SR.Diabetes, sleep apnea, obesity and cardiovascular disease: Why not address them together?World J Diabetes.2014 Jun 15;5(3):381–4. doi:10.4239/wjd.v5.i3.381
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