What is it?

Sleep apnea means that breathing stops for short periods during sleep. When you stop breathing or have reduced airflow into your lungs during sleep, you don't sleep well and you can be very tired during the day. The oxygen levels in your blood may go down, and carbon dioxide levels go up. It may lead to other problems, such as high blood pressure and heart disease.

Sleep apnea can range from mild to severe, based on how often breathing stops during sleep. For adults, breathing may stop as few as 5 times an hour (mild apnea) to 30 or more times an hour (severe apnea).

Obstructive sleep apnea is the most common type. This most often occurs because your airways are blocked or partly blocked. Central sleep apnea is less common. It happens when the brain has trouble controlling breathing. Some people have both types. That's called mixed sleep apnea.

What are the symptoms?

There are symptoms of sleep apnea that you may notice and symptoms that others may notice when you're asleep.

Symptoms you may notice include:

• Feeling extremely sleepy during the day.
• Feeling unrefreshed or tired after a night's sleep.
• Problems with memory and concentration, or mood changes.
• Morning headaches.
• A dry mouth or sore throat in the morning.

If you have a bed partner, they may notice that you:

• Have episodes of not breathing.
• Snore loudly. Almost all people who have sleep apnea snore. But not all people who snore have sleep apnea.
• Toss and turn during sleep.
• Have nighttime choking or gasping spells.

How is it diagnosed?

Your doctor will probably do a physical exam and ask about your past health. The doctor may also ask you or your bed partner about your snoring and sleep behaviour and how tired you feel during the day.

Your doctor may suggest a sleep study. Sleep studies are a series of tests that look at what happens to the body during sleep. They check for how often you stop breathing or have too little air flowing into your lungs during sleep. They also find out how much oxygen you have in your blood during sleep.

A sleep study may take place in your home. Or it might take place at a sleep centre, where you will spend the night.

If your sleep apnea doesn't improve with treatment, you may have more tests to find out what's causing it.

How is it treated?

You may be able to help treat sleep apnea by making some lifestyle changes. You could try to lose weight, sleep on your side, and avoid alcohol and medicines like sedatives before bed. Moderate to severe sleep apnea is often treated with machines that deliver air through a mask to help keep your airways open. The most studied treatments include:

• Continuous positive airway pressure (CPAP). This increases air pressure in your throat. It keeps your airway open when you breathe in. It's the most common device.
• Bi-level positive airway pressure (BPAP). You may also hear this called BiPAP. This uses different air pressures when you breathe in and out.
• Adaptive servo ventilation (ASV). It senses pauses in breathing and adjusts air pressure. It's mostly used for central sleep apnea.

You can also try oral breathing devices or nasal devices. Surgery may be an option for some people. Surgery may be done to remove enlarged tissues that are blocking the throat.

How can you care for yourself at home?

• Lose weight, if needed.
• Sleep on your side. It may help mild apnea.
• Avoid alcohol and medicines such as sleeping pills, opioids, or sedatives before bed.
• Don't smoke. If you need help quitting, talk to your doctor.
• Prop up the head of your bed.
• Treat breathing problems, such as a stuffy nose, that are caused by a cold or allergies.
• Try a continuous positive airway pressure (CPAP) breathing machine if your doctor recommends it.
• If CPAP doesn't work for you, ask your doctor if you can try other masks, settings, or breathing machines.
• Try oral breathing devices or other nasal devices.
• Talk to your doctor if your nose feels dry or bleeds, or if it gets runny or stuffy when you use a breathing machine.
• Tell your doctor if you're sleepy during the day and it affects your daily life. Don't drive or operate machinery when you're drowsy.