Severe Obstructive Sleep Apnea: Symptoms, Risks and Treatment Options

Most adults need at least seven hours of good night’s sleep.¹ While you sleep, your body repairs damaged cells and releases important hormones. Sleep also gives your heart a chance to slow down and rest.² As a result, getting quality sleep is important for your overall health and well-being.

While sleeping, some people may experience shallow or temporary pauses in breathing.— also known as sleep apnea. Sleep apnea can cause a person to repeatedly wake up throughout the night, making it difficult to get a restful night’s sleep.

If these pauses happen more often or last longer during the night, they may point to a more serious form of sleep apnea called severe obstructive sleep apnea (OSA). When untreated, severe OSA can have serious effects on your long-term health.³

Learning more about severe OSA — including its health risks and treatment options — is a great first step toward meaningful conversations with your doctor.

Understanding sleep apnea and severe sleep apnea

Across the world, sleep apnea affects over 1 billion people of all shapes, sizes, genders and ages.⁴ And more than 80% of people living with moderate severe sleep apnea are undiagnosed.⁵ Learning more about sleep apnea and understanding when the condition becomes severe can help you take charge of your sleep quality and health.

What is sleep apnea?

Sleep apnea is a condition that causes a person’s breathing to stop and start many times during sleep.⁶ These pauses in breathing may make it difficult for your body to get enough oxygen.

The most common symptoms of sleep apnea include:

• Excessive daytime sleepiness.
• Morning headaches.
• Feeling irritable or moody.
• Difficulty concentrating, struggling to feel present during the day.
• Snoring or gasping for air while you sleep.

Types of sleep apnea

Sleep apnea is broadly categorized into two main types, each with distinct underlying symptoms.⁷

• Obstructive sleep apnea (OSA) is the most common type of sleep apnea. The muscles around the throat relax to the point of collapse,⁶ restricting airflow during sleep. Breathing may become shallow or stop for seconds to minutes at a time.
• Central sleep apnea (CSA) occurs when your brain doesn’t send normal signals to the muscles that control breathing, causing breathing to pause during sleep.

How common is OSA?

OSA is a common sleep condition. OSA prevalence is generally about two to three times higher in men, although the difference narrows with age, particularly after menopause. ⁴

It’s also a growing challenge in the U.S. Researchers believe OSA will impact around 77 million people in the U.S. by the year 2050.⁸ That’s an increase of around 35% in 30 years.⁸ The study also suggests that:

• 30.4 million women may have OSA by 2050, which is an increase of 65% over 2020 numbers.⁸
• 45.9 million men may have OSA by 2050, which is an increase of 19% over 2020 numbers.⁸
• New drugs expected to positively impact OSA treatment results may only reduce these figures by around 4%, suggesting that OSA will remain a significant challenge.⁸

Early diagnosis and treatment of OSA may help reduce the severity of symptoms and lower the risk of related health concerns in the future.⁹ If you experience symptoms of sleep apnea, it’s important to talk to your doctor. They may have you take a sleep test to help get answers about what’s happening while you sleep.

What is considered severe obstructive sleep apnea?

When you take a sleep test, you’ll receive an apnea-hypopnea index (AHI) score.¹⁰ The term ‘apnea’ means you stop breathing for at least 10 seconds during sleep. ‘Hypopnea’ is when you have a partial blockage of your airway, so your breath is more shallow than normal. So, your AHI tells you how many times your breathing became shallow or paused entirely during each hour of sleep. The higher your AHI, the more severe your OSA.

The apnea-hypopnea index (AHI) indicates the severity of obstructive sleep apnea. AHI scores are grouped in the following ranges:

• Normal: AHI < 5
• Mild: AHI of 5 to 14
• Moderate: AHI of 15 to 29
• Severe: AHI of 30 or higher

Severe OSA is concerning because it’s linked to lower-than-normal oxygen levels. If your oxygen level drops below 90% during sleep, you may experience serious health issues.¹¹

Normally, blood oxygen levels while sleeping range from 96% to 100%. For people with sleep apnea, these levels can drop significantly — sometimes to lower than 88%.¹¹ Your heart, lungs and brain all run on oxygen. When oxygen levels drop, your body feels it. Repeated drops in blood oxygen during sleep cause tissue to weaken, and tissues can weaken, and in severe cases, cells may start to die.¹² This lack of oxygen is why sleep apnea is associated with serious health conditions, such as:¹²

• High blood pressure
• Heart disease
• Diabetes
• Obesity
• Depression
• Stroke
• Kidney disease

Risk factors for severe OSA

Approximately 15% of all adults in the U.S. have severe obstructive sleep apnea (OSA).¹³ Certain factors that may increase your risk of severe OSA include:¹⁴

• Obesity. People with excess weight may have increased risk of severe OSA. Individuals with obesity can have more fat deposits in their neck, which can block the upper airway.³⁴
• Sex. Severe sleep apnea is more commonly seen in men and is often diagnosed at an earlier age than women.⁴
• Neck size. People with a larger than average neck — greater than 17 inches for men and 16 inches for women — may have a higher risk of severe OSA.¹⁵
• Certain health conditions. Heart-related conditions, Type 2 diabetes, asthma and chronic obstructive pulmonary disease (COPD) are related to a higher risk of severe OSA.
• Smoking and drinking. Smoking can cause inflammation in your airway, which affects breathing. Drinking alcohol, especially before bed, can cause the muscles in your throat to relax and possibly collapse into your airway.¹⁵
• Physical characteristics. A narrow airway, a large tongue or a different jaw structure can make it more likely for your airway to become blocked.¹⁵

Special populations

Severe obstructive sleep apnea (OSA) risk may vary by population. For instance, some pregnant women develop OSA due to hormonal changes and weight gain.¹⁶ Hormonal changes may also cause OSA in women going through menopause and put them at a higher risk for severe OSA.¹⁷

Even race has an impact on your likelihood of developing OSA. The condition is much more common in Black adults than it is in non-Hispanic White adults.¹⁸ Research suggests that severe OSA is more common in minority populations. While certain risk factors exist, severe OSA can and does impact a wide variety of people regardless of gender, size or race.

Health consequences of severe obstructive sleep apnea

Left untreated, severe obstructive sleep apnea can impact your health and day-to-day function.

High blood pressure

Some people living with severe OSA may also be living with or may develop high blood pressure (hypertension). Research suggests that severe OSA can make it more difficult to control blood pressure.

Cardiovascular complications

OSA is common across cardiovascular disease—affecting up to 40%–80% of people with cardiovascular conditions.²⁰ Severe obstructive sleep apnea may also increase the risk for these heart-related conditions:

• Heart failure. OSA and heart failure have a two-way relationship. OSA can make heart failure worse, and heart failure can make OSA worse.¹⁹
• Arrhythmias. An arrhythmia is when the heart can’t maintain its normal rate or rhythm.²¹ Arrhythmias may increase the risk of sudden cardiac death.
• Stroke. The risk of stroke can rise as OSA gets worse.²²
• Pulmonary hypertension. Over time, low oxygen levels may increase the risk of pulmonary hypertension. This occurs due to an increase in the blood pressure of the lungs.²³

Metabolic dysfunction

Severe obstructive sleep apnea (OSA) can make it harder for your body to manage blood sugar levels. OSA has also been linked to increased insulin resistance. These are two characteristics associated with metabolic syndrome, which is a group of conditions that raise your risk for heart disease, diabetes and other serious health issues.²⁴

Severe obstructive sleep apnea may also increase the risk for these metabolic issues:²⁴

• Liver disease
• High cholesterol and/or lipid levels
• Weight gain

Mental health impact

Severe obstructive sleep apnea can even affect your ability to focus, think, solve problems and remember things.²⁵ Excessive daytime sleepiness may lead to brain fog, difficulty concentrating, forgetfulness or related symptoms. OSA has also been linked to depression and anxiety.²⁵ Research suggests that the risk of depression increased with higher apnea-hypopnea index (AHI) scores, indicating a relationship between the severity of OSA and depression.²⁶

Changes to your mental health may make it difficult to get through the day and may affect your social and professional life. In addition, people with severe obstructive sleep apnea have a 123% increased risk of vehicle crashes compared to people who don’t have sleep apnea.²⁷

Risk of death

People with untreated severe obstructive sleep apnea have a 3 times higher risk of dying for any reason compared to people who don’t have sleep apnea.²⁸ In one study, 42% of the participants with severe sleep apnea died of stroke or cardiovascular disease.²⁹

Early diagnosis and treatment may help reduce the risk of death in people with severe obstructive sleep apnea. Treating OSA early and sticking with your treatment may help reduce symptoms and support healthier physical and mental well-being.

Management of severe obstructive sleep apnea

Severe obstructive sleep apnea may affect your health negatively, but there are effective treatment options available.

Primary treatment approaches

Continuous positive airway pressure (CPAP) therapy is a sleep apnea treatment that helps people breathe while they sleep.³⁰ It uses a small machine placed by your bed to gently deliver a steady flow of air through a mask. CPAP is a drug-free treatment with zero medication-related side effects. A typical CPAP system includes three parts: a CPAP device, a flexible tube, and a mask that fits over your nose or over both your nose and mouth. The gentle air pressure helps keep your airway open, so you can breathe steadily throughout the night. When used as directed, it can help alleviate OSA symptoms after the first night of use.³¹

By helping you get quality, uninterrupted sleep, CPAP therapy can lead to various health benefits, like improvements in your mood, focus, memory, productivity, and energy levels.

Surgical approaches

Surgery is invasive, so it’s reserved for people who’ve tried CPAP therapy without success. For severe OSA, a doctor may recommend one of the following surgeries to help widen the airway, including:

• Uvulopalatopharyngoplasty (UPPP). UPPP may help by removing excess tissue from the throat.³²
• Hypoglossal nerve stimulation. This procedure uses an implantable device to push the tongue forward during sleep.³³
• Maxillomandibular advancement. This surgery adjusts the position of the jaw to create more space in the airway.³²

Lifestyle modification and alternative approaches

When paired with a trusted treatment like CPAP therapy, certain lifestyle changes may make severe OSA symptoms more manageable.

Good nutrition and regular exercise can help with weight management, preventing airway collapse caused by excess tissue. Avoiding alcohol and maintaining good sleep habits may also be helpful. We
recommend sleeping on your side instead of your back or stomach.

Because of the serious health risks associated with severe OSA, lifestyle changes alone are not enough. Treatment for severe sleep apnea should always be guided by a doctor to ensure safety and effectiveness.

Looking to learn more about your sleep in general? Take the sleep assessment.

References:

1. Source: Center for Disease Control. About Sleep. Cdc.gov May 15, 2024. Accessed August 24, 2026. https://www.cdc.gov/sleep/about/index.html
2. Source: Drager, Luciano F., et al. “Sleep Apnea and Cardiovascular Disease: Lessons From Recent Trials and Need for Team Science.” Circulation, vol. 136, no. 19, Nov. 2017, pp. 1840–50. DOI.org (Crossref), https://doi.org/10.1161/CIRCULATIONAHA.117.029400.
3. Source: Bonsignore, Maria R., et al. “Obstructive Sleep Apnea and Comorbidities: A Dangerous Liaison.” Multidisciplinary Respiratory Medicine, vol. 14, no. 1, Feb. 2019, p. 8. Springer Link, https://doi.org/10.1186/s40248-019-0172-9.
4. Source: Iannella G, Pace A, Bellizzi MG, et al. The Global Burden of Obstructive Sleep Apnea. Diagnostics (Basel). 2025;15(9):1088. Published 2025 Apr 25. doi:10.3390/diagnostics15091088
5. Source: Celmer, Lynn. “National Indicator Report Details Importance of OSA Diagnosis, Treatment.” American Academy of Sleep Medicine – Association for Sleep Clinicians and Researchers, 4 Apr. 2023, https://aasm.org/new-national-indicator-report-details-importance-prompt-sleep-apnea-diagnosis-treatment/.
6. Source: Sleep Apnea – What Is Sleep Apnea? | NHLBI, NIH. 9 Jan. 2025, https://www.nhlbi.nih.gov/health/sleep-apnea.
7. Source: Asp K. Obstructive vs. Central Sleep Apnea: Key Differences and Treatment Options – American Association of Sleep Technologists. American Association of Sleep Technologists. November 17, 2022. https://aastweb.org/obstructive-vs-central-sleep-apnea-key-differences-and-treatment-options/
8. Source: Boers E, Barrett MA, Benjafield AV, et al. Projecting the 30-year burden of obstructive sleep apnoea in the USA: a prospective modelling study. The Lancet Respiratory MedicinePublished online August 1, 2025.
   doi:10.1016/s2213-2600(25)00243-7
9. Source: Kapur, Vishesh K., et al. “Clinical Practice Guideline for Diagnostic Testing for Adult Obstructive Sleep Apnea: An American Academy of Sleep Medicine Clinical Practice Guideline.” Journal of Clinical Sleep Medicine, vol. 13, no. 3, Mar. 2017, pp. 479–504. Springer Link, https://doi.org/10.5664/jcsm.6506.
10. Source: Slowik JM, Sankari A, Collen JF. Obstructive Sleep Apnea. [Updated 2025 Mar 4]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2026 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK459252/
11. Source: “Normal Oxygen Levels While Sleeping.” Sleep Foundation, 23 June 2023, https://www.sleepfoundation.org/physical-health/what-are-normal-oxygen-levels-during-sleep.
12. Source: Why Is Sleep Apnea Dangerous?: Laurelton Heart Specialists: Cardiologists. https://www.topheartdoctors.com/blog/why-is-sleep-apnea-dangerous
13. Source: Ibrahim S, Alexandre Vo D, Yu K, Cronin J, Yee J, Azarbarzin A. 0635 Unmasking Obstructive Sleep Apnea: Estimated Prevalence and Impact in the United States. Sleep2025;48(Supplement_1):A277-A278. Accessed
    August 24, 2026. https://academic.oup.com/sleep/article/48/Supplement_1/A277/8135590?login=false
14. Source: Sleep Apnea – Causes and Risk Factors | NHLBI, NIH. 9 Jan. 2025, https://www.nhlbi.nih.gov/health/sleep-apnea/causes.
15. Source: Review Article 1, Issue 11.2. Aadsm.org2017. https://aadsm.org/journal/review_article_1_issue_112.php
16. Source: Tayade, S., & Toshniwal, S. (2022). Obstructive Sleep Apnea in Pregnancy: A Narrative review. Cureus, 14(10), e30387. https://doi.org/10.7759/cureus.30387
17. Source: Jehan, S., et al. (2016, August 25). Obstructive sleep Apnea: Women’s perspective. https://pmc.ncbi.nlm.nih.gov/articles/PMC5323064/
18. Source: Johnson, D. A., et al. (2022). The need for social and environmental determinants of health research to understand and intervene on racial/ethnic disparities in obstructive sleep apnea.
    Clinics in Chest Medicine, 43(2), 199–216. https://doi.org/10.1016/j.ccm.2022.02.002
19. Source: Oldenburg O, Lamp B, Faber L, Teschler H, Horstkotte D, Töpfer V. Sleep-Disordered Breathing in Patients with Symptomatic Heart Failure A Contemporary Study of Prevalence in and Characteristics of 700 Patients. European Journal of Heart Failure2007;9(3):251-257.
    doi:10.1016/j.ejheart.2006.08.003
20. Source: Yeghiazarians, Y., et al. (2021). Obstructive sleep apnea and cardiovascular disease: A scientific statement from the American Heart Association. Circulation, 144(3), e56–e67. https://doi.org/10.1161/cir.0000000000000988
21. Source: Ärzteblatt, Deutscher Ärzteverlag GmbH, Redaktion Deutsches. “Sleep Disordered Breathing in Patients with Atrial Fibrillation and Normal Systolic Left Ventricular Function (06.03.2009).” Deutsches
    Ärzteblatt, https://www.aerzteblatt.de/int/archive/article?id=63690
22. Source: Johnson KG, Johnson DC. Frequency of sleep apnea in stroke and TIA patients: a meta-analysis. J Clin Sleep Med. 2010;6(2):131-137.
23. Source: Kholdani C, Fares WH, Mohsenin V. Pulmonary hypertension in obstructive sleep apnea: is it clinically significant? A critical analysis of the association and pathophysiology. Pulm Circ.
    2015;5(2):220-227. doi:10.1086/679995
24. Source: Kuvat, Nuray, et al. “The Relationship between Obstructive Sleep Apnea Syndrome and Obesity: A New Perspective on the Pathogenesis in Terms of Organ Crosstalk.” The Clinical Respiratory Journal, vol. 14,
    no. 7, July 2020, pp. 595–604. DOI.org (Crossref), https://doi.org/10.1111/crj.13175.
25. Source: Krysta, K., et al. (2016). Cognitive deficits in adults with obstructive sleep apnea compared to children and adolescents. Journal of Neural Transmission, 124(S1), 187–201. https://doi.org/10.1007/s00702-015-1501-6
26. Source: Zhao DF, Zhang YZ, Sun X, Su CY, Zhang LQ. Association between obstructive sleep apnea severity and depression risk: a systematic review and dose-response meta-analysis. Sleep Breath.
    2024;28(5):2175-2185. doi:10.1007/s11325-024-03083-4
27. Source: Gottlieb, D. J., et al. (2018). Sleep deficiency and motor vehicle crash risk in the general population: A prospective cohort study. BMC Medicine, 16(1), 44. https://doi.org/10.1186/s12916-018-1025-7
28. Source: Young, T., et al. (2008, August 1). Sleep-disordered breathing and mortality: Eighteen-year follow-up of the Wisconsin sleep cohort. https://pmc.ncbi.nlm.nih.gov/articles/PMC2542952/
29. Source: Pietzsch JB, Garner A, Cipriano LE, Linehan JH. An integrated health-economic analysis of diagnostic and therapeutic strategies in the treatment of moderate-to-severe obstructive sleep apnea. Sleep.
    2011;34(6):695-709. Published 2011 Jun 1. doi:10.5665/SLEEP.1030
30. Source: CPAP – CPAP | NHLBI, NIH. 24 Mar. 2022, https://www.nhlbi.nih.gov/health/cpap.
31. Source: “Before and After CPAP: How Your Body Changes.” Sleep Foundation, 27 Oct. 2022, https://www.sleepfoundation.org/cpap/before-and-after-cpap-machine-body-changes.
32. Source: Carvalho, B., Hsia, J., & Capasso, R. (2012). Surgical therapy of obstructive sleep apnea: A review. Neurotherapeutics, 9(4),
    710–716. https://doi.org/10.1007/s13311-012-0141-x
33. Source: Olson, M. D., & Junna, M. R. (2021). Hypoglossal nerve stimulation therapy for the treatment of obstructive sleep apnea. Neurotherapeutics, 18(1), 91–99. https://doi.org/10.1007/s13311-021-01012-x
34. Source: Adult BMI categories. (2024, March 19). BMI. https://www.cdc.gov/bmi/adult-calculator/bmi-categories.html