What Is Sleep Apnea?

Enjoying a good night’s sleep and waking up feeling refreshed will help you enjoy the things you love.

Treating your sleep apnea can empower you to sleep sounder, awake brighter and live a healthier life.

Do I have Sleep Apnea
What Happens When You Have Sleep Apnea?

Apnea literally means “no breath” or “stopping breathing”. When you have sleep apnea, air stops flowing to your lungs for 10 seconds or longer – that is, you actually stop breathing.

This makes your blood oxygen level drop which in turn triggers your brain to wake you up just enough to take a breath.1 Then you fall back to sleep and the cycle begins again.

This can happen more than 30 times every hour and you may not even know it! As you can imagine, constantly being triggered back into breathing, hour after hour, night after night, can put a strain on your body. The next day you may feel tired and wrung out. Sleep apnea isn’t just an inconvenience. Left undiagnosed and untreated, it can have serious long-term effects on your health.2,3 3 in 10 men and almost 1 in 5 women have sleep apnea.4


Types of Sleep Apnea

Obstructive Sleep Apnea (OSA)

Central Sleep Apnea

Mixed Sleep Apnea


Obstructive sleep apnea is by far the most common type of sleep apnea. It happens when your upper airways become blocked or partially blocked when you sleep. The blockage is usually in your nose or throat. Common obstructive sleep apnea causes are:

  • Being overweight (because it adds fat around your neck and airway)
  • Having inflamed tonsils or adenoids
  • Having a blocked nose due to an allergy or cold
  • A structural problem with the shape of your nose, neck or jaw.
  • Sleeping tablets and sedatives
  • Being a smoker
  • Sleeping on your back

Loud snoring, gasping for breath and daytime tiredness are common warning signs of obstructive sleep apnea, although some people with obstructive sleep apnea don’t snore much at all.

Diagnose your sleep apnea

Less common than obstructive sleep apnea, central sleep apnea happens when your brain doesn’t tell your body to take a while breath you sleep. Because central sleep apnea doesn’t cause much in the way of snoring, it often goes unnoticed.


If you have a mixture of obstructive sleep apnea and central sleep apnea, then you have mixed sleep apnea.

Severity of Sleep Apnea

Is your sleep apnea mild, moderate or severe?6

There are degrees of severity of sleep apnea. Sleep apnea is diagnosed as mild, moderate or severe depending on how many apnea events you have per hour. An event is when there is a complete or partial loss of breath for a minimum of 10 seconds. Complete loss of breath is called an apnea. Partial loss of breath is called a hypopnea. Sleep apnea can be diagnosed by taking a home sleep test.

  1. Normal sleep: Fewer than 5 events per hour

  2. Mild sleep apnea: Between 5 and 14 events per hour

  3. Moderate sleep apnea:  15 to 29 events per hour

  4. Severe sleep apnea: 30 or more events per hour

The result of your sleep test gives you a number called an Apnea/Hypopnea Index (known as AHI). Your AHI number gives you (and your doctor) a guide to the best treatment options for you. Learn more about sleep apnea treatment.

What Causes Sleep Apnea?

Obstructive Sleep Apnea

In adults the most common cause of obstructive sleep apnea is obesity. Being overweight can add extra fat around the neck and airways. During sleep the throat and tongue muscles relax causing the airway to become blocked. But obesity is not the only cause - other factors are also associated with sleep apnea.

Learn more about what causes sleep apnea.

Central Sleep Apnea

Central sleep apnea occurs when your brain doesn’t tell your body to take a breath. It’s normally associated with other conditions such as heart failure or stroke.7

What Are the Warning Signs of Sleep Apnea?

Because you’re asleep when it happens, sleep apnea symptoms can go undetected. If you sleep with a partner, you may have been told that you snore, stop breathing or make gasping sounds in your sleep.

Daytime sleep apnea symptoms9,10 include:

Fatigue, constant tiredness and/or sleepiness
Poor concentration and forgetfulness
Morning headaches
Sexual dysfunction
Depressed mood
Weight gain
High blood pressure

How to Treat Sleep Apnea

One of the most effective ways to treat obstructive sleep apnea is with a CPAP (continuous positive airway pressure) machine. CPAP uses an air pump and specialised mask to comfortably deliver air pressure to your upper airway while you sleep.

If you're uncomfortable with the idea of a CPAP machine, your healthcare provider may recommend that you try something else. For example, some people may benefit from sleeping on their sides or sitting up in bed while they sleep.

Others use special appliances to help them breathe through their nose during the night instead of their mouth. Ultimately, Your healthcare provider can help determine what's best for you.

If your sleep apnea isn't being treated effectively on its own or if it's causing difficulties at work and home, surgery may be an option to consider. Surgery can often address major causes of sleep apnea, such as enlarged tonsils or a deviated septum.

Online sleep assessment

Do you have symptoms?

There are quite a few risk factors associated with sleep apnea if it remains untreated.

"If you suspect you may have a sleep disorder like sleep apnea, you're only a few clicks away from a better night's rest. Try this simple online sleep assessment to see if you have symptoms."

Take our free online sleep assessment
Is Sleep Apnea Related to Age or Sex?
Being a man
Men are more likely than women to have obstructive sleep apnea. An Australian study published in 2018 found that 25% of men and 13.3% of women had diagnosed or possible undiagnosed obstructive sleep apnea.11
related to age or sex-1
A woman with obstructive sleep apnea may be less likely to be diagnosed than a man. She may not snore as loudly as a man. She may notice fatigue, insomnia, headaches or mood changes. Her doctor may treat these symptoms rather than recommend a home sleep test for sleep apnea.12
Growing older-LowRes-1
Age is also related to sleep apnea. A man is most likely to be diagnosed with obstructive sleep apnea when he’s aged over 40.11 A woman is more likely to be diagnosed after menopause or during pregnancy.12

Likelihood of Having Obstructive Sleep Apnea by Age

Australian men and women diagnosed or possible undiagnosed obstructive sleep apnea by age.*
*Possible undiagnosed obstructive sleep apnea was defined as witnessed breathing pauses ≥3 times per week or witnessed breathing pauses ≥3 times per month with loud snoring ≥3 times per week.
Reference: Appleton SL et al. Sleep Health 4 (2018) 13–19

Frequently Asked Questions (FAQ’s)

Is Sleep Apnea Dangerous?

Yes, sleep apnea is a dangerous condition that can lead to numerous health problems such as high blood pressure and diabetes if left untreated.

Untreated sleep apnea can also lead to daytime sleepiness, which makes you more prone to roadside and workplace accidents.

Many people have sleep apnea and don’t even know it. If you think that you may have symptoms of this disorder, then you may want to seek the advice of your doctor and/or have a sleep study done.

Is Sleep Apnea Hereditary?

Studies have shown that obstructive sleep apnea can be hereditary, which means the condition can be passed on from one generation to another.13

Even though research has shown that there is a genetic component involved with obstructive sleep apnea, there is still no clarity on the specific genes that are involved with it.

Can Sleep Apnea Be Cured?

There is currently no cure for sleep apnea, but there are several different treatment options available for it. Note that treatment options will vary depending on the type and severity of sleep apnea that is present.

Treatment options for obstructive sleep apnea include:

  • CPAP (continuous positive airway pressure)
  • Lifestyle changes (i.e. weight loss, reducing alcohol consumption)
  • Sleeping on your side
  • Oral appliances
  • Surgery
Can a Deviated Septum Cause Sleep Apnea?

No, a deviated septum cannot cause sleep apnea, but it can increase the severity of sleep apnea present. If you have a deviated septum then your symptoms may be worse. You may also notice an increase in apnea events while you sleep.

Even though a deviated septum has not shown to be a direct cause of the condition it can be used to help identify that the condition is present in the first place.

If you are someone who has a deviated septum and believes it is affecting your sleep then it is recommended that you consult an ENT specialist to discuss the options that are available to you.

Can Being Overweight Cause Sleep Apnea?

Yes, being overweight can cause sleep apnea. Obesity and excess weight is the most common cause of obstructive sleep apnea.

Can Asthma Cause Sleep Apnea?

Asthma and sleep apnea are two conditions that often go hand-in-hand. It is important for people with asthma to be aware of the symptoms of sleep apnea to make sure they are getting the proper required treatment.

Find out what causes sleep apnea and learn if you are at risk.


What are the 5 key signs that you might have sleep apnea? How to find out for sure.


How is sleep apnea treated and what benefits can you expect from effective treatment?


What sort of toll is sleep apnea taking on your body? Find out about the long term effects.




Source: Harrington, C. The Complete Guide to a Good Night's Sleep. Pan MacMillan Australia 2014


Source: Wolk R et al. Circulation 2003; 108: 9-12.


Source: Buchner NJ et al. Am J Respir Crit Care Med 2007; 176(12): 1274-1280.


Source: Peppard PE et al. Am J Epidemiol. 2013 (5.17).


Source: Morgenthaler TI et al. Complex sleep apnea syndrome: is it a unique clinical syndrome? Sleep 2006;29(9):1203-9.


Source: Palnitkar G, et al. Medicine Today 2012, 13(8):14-23.


Source: Wong SH, Ng BY. Singapore Med J. 2015 Jun;56(6):317-23.


Source: Appleton SL et al. Sleep Health 4 (2018) 13–19


Source: https://doi.org/10.5665/sleep.1366 accessed 23 June 2021