Sleep apnea | ResMed
Sleep apnea

What is sleep apnea?

Sleep apnea is a disorder that causes your body to stop breathing while you sleep. It’s a potentially fatal condition, with harmful short- and long-term complications, that affects more than 1 in 3 men and 1 in 6 women.1


What causes sleep apnea?

There are three main types of sleep apnea:

  • Obstructive sleep apnea (OSA), which more than 80% of sleep apnea patients have, occurs when enlarged and/or relaxed throat muscles obstruct your upper airway, blocking air from entering and leaving your lungs.
  • Central sleep apnea (CSA), so named for its relation to the central nervous system, occurs when the brain stops signalling for the body to breathe until it detects a lack of oxygen and/or a heightened level of carbon dioxide that needs to be exhaled.
  • Complex sleep apnea (CompSA) is a combination of OSA and CSA. (Here are more details on the different types of sleep apnea)

Eventually your brain senses that you’ve stopped breathing and causes you to wake up just enough to gasp and start breathing again. Then you fall back to sleep and the cycle begins again. This can happen more than 120 times every hour, even though you may not remember waking up.

As you can imagine, apneas put immense short- and long-term strains on the body.


Short-term effects of sleep apnea

Of course apneas cause the immediate life-threatening danger of not inhaling enough oxygen (or exhaling enough poisonous carbon dioxide). But the body’s constant waking due to these apneas can also cause sleep deprivation. This can lower people’s energy and attentiveness the next day, negatively affect their moods and relationships with others, and raise the risk for memory loss, cognitive impairment and injury.


Long-term effects of sleep apnea

Untreated sleep apnea has been linked to an increased risk for other chronic and life-threatening conditions such as hypertension (high blood pressure)2 and heart failure,3 as well as poorer glucose control in patients with type 2 diabetes.4

The first step toward treating sleep apnea and living healthier is recognizing the signs and symptoms of sleep apnea and asking your doctor to get screened and tested.

Roughly 80% of people with sleep apnea don’t know they have it,5 partly because they can never witness their own nighttime symptoms.


Common sleep apnea symptoms

While snoring is still the strongest predictor of sleep apnea in men and women,6 not everyone who snores has it. And more important, not everyone who has it snores. Below are other common sleep apnea symptoms:

  • Constant tiredness
  • Poor concentration
  • Night sweats
  • Weight gain
  • Lack of energy
  • Forgetfulness
  • Sexual dysfunction
  • Frequent urination at night

In addition, women often show subtler, atypical symptoms such as insomnia, morning headaches, depression and anxiety.7 These symptoms often lead to misdiagnoses such as depression, insomnia or menopausal side effects.8 If you have these symptoms, be sure to ask your doctor about whether you might have sleep apnea.


Get connected to sleep apnea help

Sleep apnea is more common than you might think. If you are diagnosed with sleep apnea, you won't need to walk the journey alone. Join our free online community today—it's absolutely FREE!

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Benefits of sleep apnea treatment

The benefits of treating sleep apnea include easing common symptoms such as snoring and lack of energy.

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Sleep apnea treatment options

You can manage your sleep apnea and live a long, healthy life. The key is finding the right treatment option for your symptoms and lifestyle. Learn about the options here, and talk to your doctor before pursuing a particular option.

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Traveling with sleep apnea therapy equipment

Traveling with sleep apnea therapy? Here’s an overview of the basic steps to follow to ensure that your travel plans don’t interrupt your sleep apnea treatment.

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View your sleep apnea treatment data

It's important to make sure you’re receiving the proper sleep apnea treatment all night, every night. ResMed has a data tracker that syncs up to its machines:

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  1. Peppard PE et al. Increased prevalence of sleep-disordered breathing in adults. Am J Epidemiol 2013;177(9):1006–14.
  2. Lavie P, Herer P and Hoffstein V. Obstructive sleep apnoea syndrome as a risk factor for hypertension: Population study. Br Med J 2000;320:479–82. 
  3. Shahar E et al. Sleep-disordered breathing and cardiovascular disease: Cross-sectional results of the Sleep Heart Health study. Am J Respir Crit Care Med 2001;163(1):19–25. 
  4. Aronsohn RS et al. Impact of untreated obstructive sleep apnea on glucose control in type 2 diabetes. Am J Respir Crit Care Med 2010;181(5):507–13. 
  5. Young T et al. Estimation of the clinically diagnosed proportion of sleep apnea syndrome in middle-aged men and women. Sleep 1997;20(9):705–6. 
  6. Young T et al. The gender bias in sleep apnea diagnosis: Are women missed because they have different symptoms? Arch Intern Med 1996;156(21):2445–51. 
  7. Sadeka T and Geraci S. Major sleep disorders among women. South Med J 2013;106(8):470–8.
  8. Phillips B. National Sleep Foundation (accessed August 6, 2014).