Obstructive sleep apnea

At a glance

  • People with obstructive sleep apnea stop breathing for short periods of time at night.
  • Other typical symptoms include loud snoring at night, as well as tiredness and difficulty concentrating during the day.
  • Obstructive sleep apnea increases the risk of various cardiovascular (heart and blood vessel) diseases.
  • The most effective treatment is CPAP therapy, where a machine gently blows air into your airways at night through a special mask.


Photo of a man who is very tired

We all know what it’s like to feel tired after a sleepless night because of things like noise, worries or stress. But what if you actually get enough sleep and still feel absolutely beat the next morning? This is normal for many people with obstructive sleep (OSA): They stop breathing for short periods of time (usually without noticing) while sleeping, don’t get enough oxygen as a result, and feel very sleepy during the day. In the long term, this increases their risk of developing other illnesses and can have a huge effect on their quality of life.


People who have obstructive sleep usually snore very loudly. They regularly have phases of shallow breathing (hypopnea) and breathing pauses () that last longer than ten seconds while they are sleeping. Snoring itself is harmless; it is only classified as sleep if you have breathing pauses too.

Symptoms that may be signs of sleep include:

  • exhaustion during the day,
  • poor concentration,
  • night sweats and frequent urination,
  • waking up suddenly, sometimes with a racing heart and shortness of breath,
  • a dry mouth when you wake up,
  • headaches in the morning, and
  • erection problems (impotence).

Causes and risk factors

Sleep is caused by the muscles of the upper airways relaxing. Your throat then becomes narrow or even completely blocked, which leads to loud snoring noises when you breathe in and out.

As a result, your body doesn’t get enough oxygen. Your pulse and blood pressure fall too. The part of your brain responsible for breathing sets off an alarm and triggers a wake-up call, causing you to wake up briefly, usually without realizing it. This interrupts your natural sleep pattern, your heart starts beating faster and your blood pressure rises. These interruptions are also called “arousals.” If this keeps happening throughout the night, it may prevent you from entering deep sleep, which is what is needed to get restful sleep.

Illustration: Normal breathing
Illustration: Obstructive sleep apnea – as described in the article

People who have sleep are often very overweight or have unusual features in their mouth and throat area. These unusual features include enlarged tonsils, a small lower jaw, the position of the tongue and a small soft palate. The soft palate is the soft tissue at the back of the roof of your mouth. It is sometimes hard to breathe through your nose too. Sleeping on your back can make snoring and breathing difficulties more likely, but is rarely the only cause.

Drinking too much alcohol and taking sleeping pills or sedatives relaxes the throat muscles and can make sleep worse. The likelihood of developing obstructive sleep increases steadily after the age of 45.


It is estimated that about 5% of men and 3% of women have obstructive sleep .


Severe sleep makes you feel constantly worn out and tired. Not getting enough restful sleep can affect your mood too. If you generally feel less well than people who usually get a good night's sleep, you may also be more likely to become depressed.

People who have sleep are at greater risk of developing high blood pressure (hypertension) and other cardiovascular diseases. So they are more likely to have a heart attack, a stroke or an abnormal heart rhythm (arrhythmia).

Breathing pauses don’t always cause problems or pose a health risk. If they only occur now and then, are short, and don’t cause tiredness during the day, there’s usually no reason to worry. But it may be a good idea to keep an eye on any breathing difficulties and see a doctor if they cause more long-term problems.


If it’s thought you might have obstructive sleep , your doctor will first ask you about your symptoms and lifestyle habits. This is followed by a physical examination. You may be given a portable monitoring device which can be used when you are asleep to record things like your breathing, heart rate, blood oxygen levels, snoring, and body position. If there are any irregularities, you may be advised to have further tests in a sleep laboratory.

Sleep laboratories have special bedrooms where your sleep is monitored for one or more nights using different recording devices and a video camera. As well as recording your breathing, pulse, blood pressure and blood oxygen levels, they also record your brainwaves, and your eye and leg movements during sleep. Using the recorded data, the different sleep phases can be analyzed to see how long and how well you slept, and whether you spent enough time in deep sleep and dreaming. In people with sleep , the machines can record how often breathing pauses occur, how long they last, during which phases of sleep they occur, and the patient's sleeping position at the time. It is also possible to see how they affect the cardiovascular system and blood oxygen levels.


If you’re very overweight, losing weight can help improve sleep . Many different treatment options are offered too. These include positional therapy and other special aids such as mouth guards, as well as machines that support breathing during the night and surgery. Some of these treatments have been scientifically proven to help people with sleep .

The most effective treatment for severe sleep is called therapy. stands for “continuous positive airway pressure.” In this treatment approach, air is taken from the immediate surroundings and blown into your airways at night using low pressure. While you sleep, you wear a breathing mask that is connected to a machine called a respirator. The gentle pressure keeps the upper airways open. People who use this machine have fewer breathing pauses, or even none at all. This can noticeably improve the symptoms such as tiredness during the day. Some people feel uncomfortable and confined when wearing the mask, though. Other common side effects include a dry throat and an irritated, sometimes blocked nose.

Medication is currently not used for the treatment of sleep . There is no scientific that the available medications work.

Everyday life

Obstructive sleep can greatly affect quality of life. Sleeping poorly can make you feel tired and “beat” during the day. Some people then fall asleep involuntarily for a very short time during the day – a phenomenon known as “microsleep.” This mostly happens when sitting or during quiet and more passive situations, for example at a concert, or while reading or watching television. It can become dangerous if this happens when you’re driving. Getting too little sleep can also cause problems with concentration or memory.

Sleep can affect your relationship if loud snoring disturbs your partner’s sleep as well, making you both feel tired and irritable during the day. The breathing pauses can be frightening for partners too.

therapy is the most effective way to relieve obstructive sleep , but it can be difficult to get used to. Many don’t like the idea of wearing a breathing mask every night. Patient education programs can help you get to grips with therapy.

I did find it hard to use the machine at first, but I can’t sleep without it now.

Clara, 59 years old

Further information

A lot of people find it helpful to join a support group and chat with others facing similar issues. There are now support groups for people with sleep in many German cities.

When people are ill or need medical advice, they usually go to see their family doctor first. In our topic "Health care in Germany" you can read about how to find the right doctor – and our list of questions can help you to prepare for your appointment.

Balk EM, Moorthy D, Obadan NO et al. Diagnosis and Treatment of Obstructive Sleep Apnea in Adults (AHRQ Comparative Effectiveness Reviews; No. 32). 2011.

Deutsche Gesellschaft für Hals-Nasen-Ohren-Heilkunde, Kopf- und Hals-Chirurgie (ArGe Schlafmedizin). HNO-spezifische Therapie der obstruktiven Schlafapnoe bei Erwachsenen (S2e-Leitlinie, in Überarbeitung). AWMF-Registernr.: 017-069. 2015.

Deutsche Gesellschaft für Schlafforschung und Schlafmedizin (DGSM). Nicht erholsamer Schlaf/Schlafstörung - Schlafbezogene Atmungsstörungen (S3-Leitlinie, in Überarbeitung). AWMF-Registernr.: 063-001. 2020.

Greenstone M, Hack M. Obstructive sleep apnoea. BMJ 2014; 348: g3745.

Labarca G, Saavedra D, Dreyse J et al. Efficacy of CPAP for Improvements in Sleepiness, Cognition, Mood, and Quality of Life in Elderly Patients With OSA: Systematic Review and Meta-analysis of Randomized Controlled Trials. Chest 2020; 158(2): 751-764.

Srijithesh PR, Aghoram R, Goel A et al. Positional therapy for obstructive sleep apnoea. Cochrane Database Syst Rev 2019; (5): CD010990.

Thomasouli MA, Brady EM, Davies MJ et al. The impact of diet and lifestyle management strategies for obstructive sleep apnoea in adults: a systematic review and meta-analysis of randomised controlled trials. Sleep Breath 2013; 17(3): 925-935.

Timkova V, Nagyova I, Reijneveld SA et al. Quality of life of obstructive sleep apnoea patients receiving continuous positive airway pressure treatment: A systematic review and meta-analysis. Heart Lung 2020; 49(1): 10-24.

IQWiG health information is written with the aim of helping people understand the advantages and disadvantages of the main treatment options and health care services.

Because IQWiG is a German institute, some of the information provided here is specific to the German health care system. The suitability of any of the described options in an individual case can be determined by talking to a doctor. informedhealth.org can provide support for talks with doctors and other medical professionals, but cannot replace them. We do not offer individual consultations.

Our information is based on the results of good-quality studies. It is written by a team of health care professionals, scientists and editors, and reviewed by external experts. You can find a detailed description of how our health information is produced and updated in our methods.

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Updated on December 19, 2022

Next planned update: 2025


Institute for Quality and Efficiency in Health Care (IQWiG, Germany)

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