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Sleep Apnea

Sleep apnea makes your body’s stress response system work very hard during the night to keep you breathing.

You may have sleep apnea if you:

  • snore loudly
  • feel very tired during the day
  • stop breathing at night (other people may have noticed)
  • have high blood pressure

Ask your doctor if you should go for a sleep test.

The word apnea means “no breath”. Sleep apnea is when you pause in your breathing or have shallow breathing while you sleep. This pause can last anywhere from 10 seconds to several minutes.

If you have sleep apnea, the airway to your lungs becomes blocked when you sleep.

  • When you are lying down during sleep, your tongue and the tissues behind it can sag back into your throat and block the airway. This causes you to snore loudly.
  • When your airway is blocked your lungs do not get air. This causes your brain to start the stress response system in your body.
  • The stress response wakes you up so you can start breathing again. This stress response can happen every few minutes during your sleep. This means that you are in a “high stress” state all night long. You do not get good deep sleep at night.
  • The cycle of stopping breathing and starting the stress system to breathe again can happen as many as 60 times during every hour of sleep.

There are three types of sleep apnea.

  • Mild: When you have less than 15 breathing stoppages per hour
  • Moderate: When you have between 15 and 29 breathing stoppages per hour
  • Severe: When you have greater than 30 breathing stoppages per hour

How Does Sleep Apnea Affect My Heart?

If you have sleep apnea, your body’s stress response system works very hard during the night to keep you breathing.

Over the years, having sleep apnea reduces the amount of oxygen in your blood at night. This causes problems to the:

  • brain
  • blood sugar level
  • immune system (how your body fights infection)
  • heart
    • Causes plaque buildup in the arteries
    • Makes your blood stickier and more likely to clot
    • Makes your heart beat faster
    • Enlarges your heart which makes it weak and have to work harder

How Do I Know If I Have Sleep Apnea?

Not everyone with sleep apnea knows they have it. But there are four signs that indicate that you might have “sleep apnea syndrome”.

Do these statements apply to you?

  • I snore loudly at night.
  • I am very tired throughout the day.
  • Someone else sees me stop breathing at night.
  • I have high blood pressure.

Note: If you are living with heart failure, you may not have these symptoms but could still have sleep apnea. 

Take action if you have any of the signs of sleep apnea syndrome or if you think you have sleep apnea.

  • Talk to your doctor.
  • Have an all-night sleep test at a sleep lab. This means that you go to a sleep lab overnight where you will be monitored as you sleep. Your brain wave activity, breathing patterns and the oxygen levels in your blood will be tracked. Once you get your results, you will be able to decide what to do next.

Take Action

You may be able to correct sleep apnea by making some sleep or lifestyle changes.

Change your sleep patterns

  • Do not sleep on your back.
  • Use a nasal strip at night to improve your breathing.
  • Ask your dentist about a dental appliance to help keep your throat open.

Make changes to your lifestyle

  • Maintain a healthy weight. If you are overweight, losing weight could reduce snoring and apneas.
  • Be active everyday.

What Do I Do If My Sleep Test Says I Have Severe Sleep Apnea?

With severe sleep apnea, you need to help your lungs and heart to function normally again at night. This usually means that you need to use a Positive Airway Pressure (PAP) machine when you sleep at night.

PAP machines work by pushing air through your airway at a relatively high pressure. The high pressure prevents you from stopping breathing. There are two types of PAP machines:

  1. Continuous positive airway pressure machines (CPAP) give you airway pressure continuously
  2. Assisted positive airway pressure machines (APAP) give you airway pressure when you need it

A PAP machine is about the size of a shoebox or smaller. A flexible tube connects the machine to a mask you wear over your nose and mouth.

There are many different sleep masks available to help make you comfortable when you are using the machine. Try on different masks until you find one that fits and is comfortable for you.


  1. Your Guide to Healthy Sleep. National Heart, Lung, and Blood Institute, National Institutes of Health (opens in new window)
  2. What Is Sleep Apnea? National Heart, Lung, and Blood Institute, National Institutes of Health (opens in new window)
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