What Is Obstructive Sleep Apnea? Everything to Know

Medically Reviewed By Meir Kryger, MD, FRCP(C)
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Obstructive sleep apnea (OSA) occurs when the airways completely collapse and you have periods of no breathing. It may also occur when airways partially collapse, and you have shallow breathing. This condition causes disrupted sleep and may lead to health complications. With OSA, air does not flow properly to the lungs. It usually occurs due to the tongue and soft tissue at the back of the throat collapsing while you sleep. If you have OSA, you may experience periods where you do not breathe. You may also experience periods where little or no airflow reaches the lungs.

Obstructive sleep apnea can cause you to wake up through the night. In addition to making you feel tired, OSA can result in other health complications if you do not receive treatment.

Read on to learn more about obstructive sleep apnea. This guide includes information about symptoms, causes, possible complications of OSA, and when to contact a doctor.

What are the symptoms of obstructive sleep apnea?

A woman is sleeping in a bed.
Ivan Gener/Stocksy United

Symptoms of obstructive sleep apnea can affect you both while you sleep and during the day.

OSA symptoms while you sleep include:

  • waking up gasping or choking
  • waking up with your heart pounding fast or slow
  • tossing and turning or restless sleep
  • often waking up through the night
  • having to go to the bathroom at night

Bedpartners of people with OSA may observe symptoms, such as:

  • loud snoring that may come and go
  • gasping or choking sounds
  • pauses in breathing
  • struggling to breathe
  • sudden or jerky movements

While you are awake, OSA symptoms can include:

  • feeling like you have not slept enough
  • severe daytime sleepiness
  • tiredness
  • fatigue
  • having a headache in the morning
  • sore or dry throat in the morning
  • changes in your personality, such as mood swings
  • difficulties concentrating
  • poor memory

Contact your doctor if you have symptoms of obstructive sleep apnea.

How common is obstructive sleep apnea?

The exact prevalence of obstructive sleep apnea is unclear. However, it is present in around 2–14% of community-screened populations. Additionally, it exists in 20–90% of people with a sleep study referral.

Males (assigned at birth) are three times more likely to get obstructive sleep apnea than females. It is most prevalent among people with obesity, unusual jaw structure, and people over the age of 60.

How is obstructive sleep apnea treated?

Treatments for OSA typically focus on continuous positive airway pressure (CPAP). Medical professionals consider this the gold standard for obstructive sleep apnea treatment.

What is CPAP?

CPAP treatment involves sleeping with the aid of a machine that helps to keep your airways open. While you sleep, you wear either a face mask or a nasal mask connected by a hose to a CPAP machine. This machine provides a continuous flow of air to open up your airways.

CPAP machines can have a humidifier chamber and different pressure settings, which may be fixed or auto-adjusting. Your doctor will be able to advise on which CPAP machine settings and type of CPAP mask will be best for you.

Other obstructive sleep apnea treatments

Other treatments for obstructive sleep apnea include:

  • mandibular advancement devices, which help to move the tongue and keep the airways open
  • losing weight and maintaining a healthy body weight
  • surgery if you do not respond to CPAP treatments

Learn more about sleep apnea treatments.

Will I require surgery for obstructive sleep apnea?

If you do not respond to CPAP treatments, your doctor may recommend surgery for obstructive sleep apnea. Surgeries for this condition can include:

  • hypoglossal nerve stimulation
  • uvulopalatopharyngoplasty surgery
  • maxillomandibular advancement (MMA)
  • bariatric surgery

Hypoglossal nerve stimulation involves implanting a pacemaker-like system that stimulates specific nerves in the tongue muscle. Ear, nose, and throat surgeons perform this procedure. Not all people are candidates for this treatment.

During uvulopalatopharyngoplasty surgery, your surgeon will remove excess tissue from the soft palate and uvula. This helps to remove obstructions while also reducing vibrations associated with snoring. In some cases, your surgeon may also remove your tonsils and adenoids. This is a minimally invasive procedure.

MMA is a double-jaw surgery where the surgeon will move the upper and lower jaws forward to relieve “choking points.” This procedure is up to 90% effective for people with OSA. MMA is a major surgery with a potentially difficult recovery period during the first 4–6 weeks following the operation. Therefore, your doctor will generally only recommend MMA if you do not respond to other treatments.

Over 70% of people with obstructive sleep apnea have obesity. If obstructive sleep apnea occurs due to being overweight or obese, your doctor will come up with a plan to help you lose weight. In some cases, they may recommend bariatric surgery.

What causes obstructive sleep apnea?

Obstructive sleep apnea can occur due to genetic, lifestyle, and health-based factors. Variations in multiple genes can combine to increase your risk of developing OSA.

Genes that can contribute to the development of OSA are involved in:

  • communications between nerve cells
  • regulating breathing
  • controlling inflammatory responses by the immune system
  • developing tissues in the head and face
  • sleep-wake cycle
  • controlling appetite

Obesity can also cause obstructive sleep apnea. Up to 70% of people with the condition in North America also have obesity. Obesity contributes to OSA as excess fatty tissue in the head and neck causes the airways to be unusually small and crowded. At the same time, abdominal fat can prevent the lungs and chest from fully expanding and relaxing.

In some cases, OSA may occur due to a different condition. These conditions can include mucopolysaccharidosis type I and polycystic ovary syndrome (PCOS).

Visit our sleep disorders hub for more information about conditions that can affect your sleep.

When should I contact a doctor?

Contact a doctor as soon as you experience symptoms of obstructive sleep apnea. As the condition can lead to health complications, it is important to receive a diagnosis and begin treatment as soon as possible.

Find out about which types of doctors treat sleep apnea.

How is obstructive sleep apnea diagnosed?

To diagnose obstructive sleep apnea, your doctor will carry out a physical examination. They will also ask about your symptoms, medical and family history, and arrange for a sleep study, or polysomnogram, if they feel you may be experiencing OSA.

Physical examination

During your physical examination, your doctor will look for various contributors to OSA, including:

  • larger neck circumference
  • high body mass index (BMI)
  • posterior chin positioning
  • narrow oropharyngeal opening
  • reduced distance from the chin to the thyroid cartilage
  • increased angles from the chin to the thyroid cartilage

STOP-Bang questionnaire

Your doctor will ask you questions in line with the STOP-Bang questionnaire, which experts designed as a concise and easy-to-use screening tool for OSA.

Each letter of the acronym stands for a different symptom of, or contributor to, obstructive sleep apnea. Related questions your doctor may ask are as follows:

  • Snoring: Do you snore loudly?
  • Tiredness: Do you feel tired or sleepy during the day?
  • Observed apnea: Has anybody noticed that you stop breathing or make choking or gasping sounds while sleeping?
  • High blood pressure: Do you have high blood pressure, or have you previously received treatment for high blood pressure?
  • BMI: Is your body mass index greater than 35 kg/m2?
  • Age: Are you over the age of 50?
  • Neck: Is the circumference of your neck greater than 40 cm (15.75 inches)?
  • Gender: Are you male?

Sleep study

A sleep study will typically occur at a sleep center or clinic where a medical professional monitors your vital signs while you sleep. However, you may also be able to carry out the sleep study at home.

A sleep test monitors your:

  • breathing
  • heart rate
  • oxygen levels

The study will record the number of apneas or hypopneas during the test. Apnea refers to a completely obstructed airflow, while hypopnea is a partial obstruction. Each must last for at least 10 seconds.

A professional will combine the number of apneas and hypopneas you experience and then divide it by the total sleep time. This number is your apnea-hypopnea index (AHI) score. An AHI score of 15, around 5 or more apneas or hypopneas per hour, can indicate obstructive sleep apnea.

Find out more about what happens during a sleep study.

What are the risk factors for obstructive sleep apnea?

Various risk factors may make you more likely to develop obstructive sleep apnea. These include:

  • having obesity
  • drinking alcohol
  • having frequent nasal congestion
  • having enlarged tonsils that block the airways
  • being older than 60 years
  • being assigned male at birth, as males are three times more likely to get OSA than females

What are the complications of obstructive sleep apnea?

If you have obstructive sleep apnea, you may experience health complications. You may also face potential risks to your safety due to tiredness or memory problems.

Health complications can include:

Secondary complications include:

  • motor vehicle collisions
  • work-related injury
  • accidental injury

Contact your doctor if you experience symptoms of obstructive sleep apnea. Early diagnosis and treatment can help to reduce your risk of complications.

What is the difference between sleep apnea and obstructive sleep apnea?

Sleep apnea is an overarching term that refers to disruptions in breathing while you sleep. This can be apnea, where there is a period of no breathing, or hypopnea, which refers to shallow breathing.

There are three types of sleep apnea: obstructive sleep apnea, central sleep apnea, and complex sleep apnea.

What is the difference between central sleep apnea and obstructive sleep apnea?

The difference between central sleep apnea and OSA is the cause of the disruption to your breathing. With OSA, you experience apnea or hypopnea due to obstructions or blockages in the airways. In contrast, central sleep apnea occurs due to your brain not sending regular signals to your muscles to tell them to breathe.


Obstructive sleep apnea refers to periods of no breathing or shallow breathing due to full or partial obstructions in your upper airways. This can occur as a result of genetics, obesity, or other health conditions.

If you have OSA, you may snore loudly, and other people may observe you making choking or gasping sounds while you sleep. During the day, you may feel tired, have difficulty concentrating, and experience poor memory.

Contact your doctor if you have symptoms of obstructive sleep apnea. They will carry out a physical exam, ask you questions in line with the STOP-Bang questionnaire, and refer you to a sleep clinic if necessary. Early diagnosis and treatment can help to reduce your risk of complications.

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Medical Reviewer: Meir Kryger, MD, FRCP(C)
Last Review Date: 2022 Jun 8
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THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
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