Obstructive sleep apnoea

Also known as OSA

Obstructive sleep apnoea (OSA) is a condition when people stop breathing while they are asleep.

When someone with OSA is asleep, the tissues in their airways relax and can block the airways. When this happens, it causes them to momentarily stop breathing until the brain wakens them to begin breathing again. This cycle can repeat hundreds of times a night, and often the sufferer is unaware of the problem.

Who is affected?

The condition can affect men or women at any age, but is more common in men, particularly when overweight, age 40 or over and in Maori or Pacific people.

The Thoracic Society of Australia and New Zealand estimates obstructive sleep apnoea affects about 16,000 adults and 2% of children in New Zealand. Costs to taxpayers are thought to be approximately $40 million per year (lost production, medical costs and increased risk of accidents and other illnesses such as hypertension, diabetes, cardiovascular disease and respiratory failure).


Some of the symptoms of OSA include:

  • waking in the morning feeling tired and groggy
  • having headaches and feeling sleepy during the day
  • difficulty concentrating and finishing tasks
  • being overweight
  • having high blood pressure
  • stopping breathing during sleep for 10 seconds or longer (your partner can report this)
  • waking up frequently for no apparent reason
  • getting up two or three times a night to urinate.


A detailed history of the problem and examination of the throat for signs of narrowing can help diagnose OSA. The key symptom is snoring, particularly in conjunction with daytime or early evening sleepiness. It may often be helpful for the person's spouse or partner to be present, as they can explain what happens to the person during sleep.

Tests may be used to confirm the diagnosis of OSA. Often, a simple home monitor can be used to assess long-term risk and treatment can be started based on your history of snoring and tiredness.

Polysomnography is a detailed sleep study to see how well you sleep and records a number of measurements such as any pauses in your breathing, brain wave activity, your sleep cycle (amount of deep sleep and rapid eye movement sleep) and more.


Dental appliances, such as special mouthguards and other devices, assist some people with very mild OSA but are generally intended only for those patients who have snoring without symptoms of associated sleep disturbance.

Surgery might be helpful when specific abnormalities, such as enlarged tonsils or a blocked nose, are found that are contributing to the condition. However, results of surgery in patients without specific abnormalities are often disappointing if there is any degree of OSA.

Continuous positive airway pressure 

Continuous positive airway pressure (CPAP) involves the use of a small bedside flow generator which increases the air pressure in the upper airway via tubing and a mask fitted to the nose. It is the gold standard treatment for OSA as it helps hold the airways open allowing you to sleep properly. Better quality sleep leads to less daytime sleepiness and reduces the increased risk of high blood pressure, heart disease, stroke etc.

Modern CPAP technology has become easier and more comfortable to use such that thousands of New Zealanders are using it to not only control OSA, but also for snoring. The slight increase in air pressure effectively splints the airway so it remains as open as it is when awake. CPAP is the only treatment for snoring and sleep apnoea which is guaranteed to work.

Many people find they feel much better within a few days of commencing CPAP, as they get the benefit of deep restorative sleep that they previously lacked.

When to see your doctor

If you have a sleep problem, you should seek medical advice if:

  • you have had insomnia for months
  • lack of sleep is interfering with your ability to function normally during the day
  • you have early morning waking, mood changes or feel under stress
  • you wake often to go to the toilet (for men, this may be a sign of prostate problems)
  • you are being woken by pain
  • you are taking prescription medicines that are interfering with your sleep
  • you have untreated respiratory, cardiovascular or gastrointestinal disease symptoms.

Learn more

The following links take you to other websites that provide further information on OSA. Be aware that websites from other countries may contain information that differs from New Zealand recommendations.

Obstructive sleep apnoea Kidshealth NZ and Paediatric Society of NZ and Starship Foundation, 2013 
Obstructive sleep apnoea Southern Cross Healthcare Group NZ, 2013
Information sheets and videos Sleep Apnoea Association of NZ Inc. (SAANZ) 

Credits: Reviewed by Bryn Sparks, sleep physiologist, Sleep Well Clinic, August 2008. Updated by Health Navigator May 2014.