Sleep Apnoea: Symptoms, Risks and Treatment

What is sleep apnoea?

In obstructive sleep apnoea (often spelled “sleep apnea”), the muscles of the throat relax during sleep and the airway narrows or closes. Breathing stops or becomes very shallow for ten seconds or more, oxygen levels dip, and the brain briefly rouses you to reopen the airway. This can happen hundreds of times a night without you remembering any of it.¹³

It is very common. A global analysis estimated that almost one billion adults aged 30 to 69 have obstructive sleep apnoea, most of them undiagnosed.¹

Sleep apnoea symptoms

At night:

• Loud snoring
• Pauses in breathing, noticed by a partner
• Waking with a gasp or a choking feeling
• Restless sleep and getting up to pass urine
• Night sweats. Frequent night-time sweating is about three times more common in people with untreated sleep apnoea than in the general population¹²

During the day:

• Waking unrefreshed, often with a dry mouth or headache
• Sleepiness, including dozing off when sitting quietly
• Poor concentration, irritability and low mood

Not everyone with sleep apnoea snores loudly or feels sleepy. Women more often report tiredness, poor sleep and low mood.

What causes it?

Anything that narrows the airway or relaxes the throat. The main risk factors are carrying extra weight, a large neck size, being male, getting older, menopause, the shape of your jaw and throat, a blocked nose, and alcohol. A meta-analysis found that higher alcohol intake raised the risk of sleep apnoea by 25 per cent.^10,13

Can sleep apnoea kill you?

People very rarely die from an apnoea itself, because the brain wakes you to breathe. The danger is what years of broken sleep and low oxygen do.

• Crashes. A meta-analysis concluded that untreated sleep apnoea is a significant contributor to motor vehicle crashes⁷
• Heart and blood vessels. Sleep apnoea is linked with high blood pressure, heart disease and stroke
• Survival. In a study that followed more than 1,500 adults for 18 years, people with severe untreated sleep-disordered breathing were about three times as likely to die during follow-up as people without it, after allowing for age, sex and weight⁹

How is sleep apnoea diagnosed?

With a sleep study, which records your breathing, oxygen levels and sleep overnight. It can be done in a sleep laboratory or, for many adults, at home with portable equipment.²

Your GP will usually start with a short questionnaire such as STOP-Bang, which scores snoring, tiredness, observed pauses, blood pressure, body mass index, age, neck size and sex to estimate your risk.⁸ In Australia, your GP can refer you for a sleep study.¹³

Sleep apnoea treatment

• CPAP. A small pump delivers air through a mask to hold the airway open. It is the most effective treatment and is recommended for people with sleepiness, poor sleep-related quality of life or high blood pressure³
• Oral appliances. A custom-made splint, fitted by a dentist, holds the lower jaw forward. It is an option for people who can’t tolerate CPAP or prefer not to use it⁴
• Weight loss. Recommended for people with sleep apnoea who are overweight. It reduces the severity of the condition and improves blood pressure and quality of life⁵
• Positional therapy. For people whose apnoea happens mainly on their back, devices that keep you on your side reduce breathing pauses, though less than CPAP does¹¹
• Less alcohol, especially in the evening¹⁰
• Surgery for a small number of people with a clear physical blockage¹⁴

Does CPAP protect the heart?

This is less clear than once hoped. In a large international trial led from Australia, CPAP did not reduce heart attacks or strokes in people who already had cardiovascular disease.⁶ It did reduce snoring and daytime sleepiness and improved mood and quality of life, and those remain the main reasons to treat sleep apnoea.

When to see a doctor

• You snore loudly and feel tired or sleepy most days
• Someone has seen you stop breathing, gasp or choke in your sleep
• You have fallen asleep, or nearly, while driving. Don’t drive when sleepy, and tell your doctor
• Your blood pressure is hard to control

More on how it is assessed and treated in Australia is available from the Sleep Health Foundation and the Better Health Channel.^14,15

References

1. Benjafield AV, Ayas NT, Eastwood PR, et al. Estimation of the global prevalence and burden of obstructive sleep apnoea: a literature-based analysis. Lancet Respir Med. 2019;7(8):687-698.
2. Kapur VK, Auckley DH, Chowdhuri S, et al. Clinical Practice Guideline for Diagnostic Testing for Adult Obstructive Sleep Apnea: An American Academy of Sleep Medicine Clinical Practice Guideline. J Clin Sleep Med. 2017;13(3):479-504.
3. Patil SP, Ayappa IA, Caples SM, et al. Treatment of Adult Obstructive Sleep Apnea with Positive Airway Pressure: An American Academy of Sleep Medicine Clinical Practice Guideline. J Clin Sleep Med. 2019;15(2):335-343.
4. Ramar K, Dort LC, Katz SG, et al. Clinical Practice Guideline for the Treatment of Obstructive Sleep Apnea and Snoring with Oral Appliance Therapy: An Update for 2015. J Clin Sleep Med. 2015;11(7):773-827.
5. Hudgel DW, Patel SR, Ahasic AM, et al. The Role of Weight Management in the Treatment of Adult Obstructive Sleep Apnea. An Official American Thoracic Society Clinical Practice Guideline. Am J Respir Crit Care Med. 2018;198(6):e70-e87.
6. McEvoy RD, Antic NA, Heeley E, et al. CPAP for Prevention of Cardiovascular Events in Obstructive Sleep Apnea. N Engl J Med. 2016;375(10):919-31.
7. Tregear S, Reston J, Schoelles K, et al. Obstructive sleep apnea and risk of motor vehicle crash: systematic review and meta-analysis. J Clin Sleep Med. 2009;5(6):573-81.
8. Chung F, Abdullah HR, Liao P. STOP-Bang Questionnaire: A Practical Approach to Screen for Obstructive Sleep Apnea. Chest. 2016;149(3):631-8.
9. Young T, Finn L, Peppard PE, et al. Sleep disordered breathing and mortality: eighteen-year follow-up of the Wisconsin sleep cohort. Sleep. 2008;31(8):1071-8.
10. Simou E, Britton J, Leonardi-Bee J. Alcohol and the risk of sleep apnoea: a systematic review and meta-analysis. Sleep Med. 2018;42:38-46.
11. Srijithesh PR, Aghoram R, Goel A, et al. Positional therapy for obstructive sleep apnoea. Cochrane Database Syst Rev. 2019;5(5):CD010990.
12. Arnardottir ES, Janson C, Bjornsdottir E, et al. Nocturnal sweating--a common symptom of obstructive sleep apnoea: the Icelandic sleep apnoea cohort. BMJ Open. 2013;3(5).
13. healthdirect. Obstructive sleep apnoea.
14. Sleep Health Foundation. Obstructive sleep apnoea.
15. Better Health Channel (Victorian Government). Sleep apnoea.