Obstructive sleep apnoea | Mate hoto hau

Obstructive sleep apnoea (OSA or mate hoto hau) is a condition where you stop breathing while you are asleep.

Key points about obstructive sleep apnoea (OSA)

  1. OSA affects about 10% of women and 25% of men.
  2. OSA is caused by the muscles in your airways relaxing and blocking your airways You then stop breathing for a short time until your brain wakes you up.
  3. Obesity is the most common and most important risk factor for OSA.
  4. Symptoms include snoring, daytime sleepiness, waking up a lot at night or stopping breathing during sleep multiple times.
  5. OSA is diagnosed through a detailed history and tests such as a sleep study.
  6. Treatment can include simple lifestyle measures, continuous positive airway pressure (CPAP), dental or oral appliances and surgery.

See your GP as soon as possible if you feel very sleepy during the day while driving or your job involves operating machinery or aircraft.


What are the causes of obstructive sleep apnoea?

If you have OSA, the muscles in your airways relax and block your airways while you are asleep. When this happens, you stop breathing for a short time until your brain wakes you up to begin breathing again. This cycle can repeat hundreds of times a night. Often you don't know this is happening, but it can reduce the quality of your sleep.

You are at higher risk of getting obstructive sleep apnoea if you:

  • are obese (the most important risk factor)
  • are a man (men are 2 times more likely to get OSA than women)
  • aged 40 or over
  • are Māori or Pasifika
  • have a family history of OSA
  • have a small jaw, small throat or nose/throat abnormalities
  • have a neuromuscular disease
  • are pregnant or have pre-eclampsia
  • have hypothyroidism
  • have polycystic ovary syndrome (PCOS)
  • have big tonsils (most common in young people).

What are the symptoms of obstructive sleep apnoea?

Symptoms of OSA include:

  • snoring
  • waking up in the morning feeling tired (daytime sleepiness) and groggy
  • having early morning headaches 
  • difficulty concentrating and finishing tasks
  • altered mood
  • stopping breathing during sleep for 10 seconds or longer (your partner can report this)
  • waking up frequently with choking
  • a dry mouth or sore throat for no apparent reason
  • getting up 2 or 3 times a night to go to the toilet.

Some of the symptoms of OSA are similar to other conditions, so it’s important to see your doctor to find out what is causing your symptoms.

See your GP or family doctor if you experience any of the following: 

  • you have had insomnia for months
  • lack of sleep is interfering with your ability to function normally during the day, eg, drowsy driving
  • you have early morning wakening, mood changes or feel under stress
  • you wake up often at night to go to the toilet (for men, this may also be a sign of prostate problems)
  • you are being woken up by pain
  • you are taking prescription medicines that are interfering with your sleep
  • you have untreated respiratory (lungs and airways), cardiovascular (heart and blood vessels) or gastrointestinal (gut) disease symptoms.

What are the complications of obstructive sleep apnoea?

If left untreated, OSA can cause:

  • poor sleep quality
  • poor work performance
  • work accidents if you have a high-risk occupation, eg, heavy machine operator
  • motor vehicle accidents
  • short-term memory problems
  • depression
  • hypertension (high blood pressure)
  • arrhythmia (irregular heartbeat)
  • cardiovascular diseases such as heart disease and stroke
  • impaired development in children.

How is obstructive sleep apnoea diagnosed?

Your doctor will take a detailed history of your problem and examine your throat, neck or nose for signs of narrowing. Your doctor will also review your medicines to find out if any of them is causing your sleepiness. You may also be asked to complete a questionnaire, called the Epworth sleepiness score (ESS). It may often be helpful for your spouse or partner to be present, as they can explain what happens to you during sleep.

Tests may be used to confirm the diagnosis of OSA, including:

Sleep study or polysomnography

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

How is obstructive sleep apnoea treated?

Treatment depends on the severity of your OSA. If you have mild OSA, such as snoring only without daytime sleepiness, it can be treated through lifestyle changes. If your OSA is more severe, treatment may include continuous positive airway pressure (CPAP), dental or oral appliances, or surgery.

Lifestyle changes

Changes that can help your OSA include:

  • losing weight if you are obese or overweight (reducing your weight as little as 10kg can make a big difference)
  • quitting smoking if you smoke
  • avoiding alcohol and medicines that make you sleepy before bed
  • exercising regularly
  • avoiding sleeping on your back
  • maintaining good sleep habits and sleep hygiene. Read our sleep tips to help with this.

Continuous positive airway pressure (CPAP)

Continuous positive airway pressure (CPAP) is the most commonly prescribed treatment for OSA. It uses a small air pump that produces pressure to keep your airway open while you sleep. You wear a mask fitted to your nose. It is the gold standard treatment for OSA as it helps hold your airways open, allowing you to sleep properly.

CPAP should be used for at least 5 nights per week and a minimum of 5 hours per night. Many people feel much better within a few days of beginning CPAP, as they get the benefit of deep restorative sleep.

Dental or oral appliances

Dental appliances, such as special mouthguards and other devices, can be used if you have less severe OSA, are not obese or can’t use CPAP.

Surgery

Surgery might be helpful when specific abnormalities, such as enlarged tonsils or a blocked nose, are contributing to the condition. There is also some evidence that it might be an option for some other people if CPAP doesn't work for them. 

Sleepiness and driving

One of the main symptoms of OSA is daytime sleepiness and fatigue. If you need to drive, this can be extremely dangerous as driver fatigue is one of the most common causes of motor vehicle accidents in New Zealand.

If you experience drowsiness while you are driving, it's important to let your doctor know. They will need to find out the causes of your sleepiness and treat it accordingly. 

It is also a legal requirement for you to only drive when you are medically fit, which means not to drive if you are too tired and sleepy. The New Zealand Transport Agency has some fatigue resources to make it easier to manage driver fatigue. See also drowsy driving tips.

See your GP as soon as possible if you feel very sleepy during the day while driving or your job involves operating machinery or aircraft.

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 Asthma + Respiratory Foundation, NZ
Information sheets and videos Sleep Apnoea Association of NZ (SAANZ) 
Fatigue resources New Zealand Transport Agency
Drowsy driving tips University of Otago, Wellington Sleep Investigation Centre, NZ
Sleep hygiene 3D HealthPathways, NZ
Obstructive sleep apnoea and CPAP therapy Well Sleep, University of Otago, Wellington, NZ
Obstructive sleep apnoea syndrome Patient Info, UK 

References

  1. Obstructive sleep apnoea in adults 3D Regional HealthPathways, NZ, 2020
  2. Obstructive sleep apnoea in adults BPAC, NZ, 2012
  3. Medical aspects of fitness to drive – a guide for health practitioners New Zealand Transport Agency, 2014
  4. MacKay S, Carney AS, Catcheside PG, et al. Effect of multilevel upper airway surgery vs medical management on the Apnea-Hypopnea Index and patient-reported daytime sleepiness among patients with moderate or severe obstructive sleep apnea: The SAMS randomized clinical trial JAMA. 2020;324(12):1168-1179. doi:10.1001/jama.2020.14265

Reviewed by

Dr Helen Kenealy is a geriatrician and general physician working at Counties Manukau DHB. She has a broad range of interests and has worked in a variety of settings including inpatient rehabilitation, orthgeriatrics and community geriatrics.
Credits: Health Navigator Editorial Team. Reviewed By: Dr Helen Kenealy, geriatrician and general physician, Counties Manukau DHB Last reviewed: 22 Feb 2021