Sleep apnea is a disorder that causes you to stop breathing while asleep. Your brain tries to protect you by waking you up enough to breathe, but this prevents restful, healthy sleep. Over time, this condition can cause serious complications. However, this condition is often very manageable, especially with close adherence to prescribed treatments.
Sleep apnea is a condition that causes you to stop breathing while you’re sleeping. The word “apnea” comes from the Greek word for “breathless.” Sleep apnea happens because you stop breathing in your sleep. This happens either because of blockage of your airway (obstructive sleep apnea) or because your brain doesn’t correctly control your breathing (central apnea).
The resulting lack of oxygen activates a survival reflex that wakes you up just enough to resume breathing. While that reflex keeps you alive, it also interrupts your sleep cycle. That prevents restful sleep and can have other effects, including putting stress on your heart that can have potentially deadly consequences.
Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
Sleep apnea can happen to anyone, ranging from infants and children to older adults. Obstructive sleep apnea is more common in certain circumstances and groups of people:
Central sleep apnea is most common in certain groups of people:
Sleep apnea is uncommon but widespread. Experts estimate it affects about 5% to 10% of people worldwide.
To understand how sleep apnea works, it helps to know a little bit about the human sleep cycle. Sleep happens in multiple stages:
When you fall asleep, you typically enter Stage 1, and then move into and cycle between Stages 2 and 3. After cycling between those stages, you’ll ultimately go into REM sleep and start dreaming. After the first REM cycle, you start a new cycle and go back into Stage 1 or 2. One cycle normally takes about 90 to 110 minutes before another begins. Most people go through four or five cycles per night (assuming they get a full eight hours of sleep).
Your brain constantly monitors your body’s status and adjusts your heart rate, blood pressure, breathing, etc. Your blood oxygen levels can drop when you stop breathing because of either apnea or hypopnea.
Your brain reacts to blood oxygen drops — from either apnea or hypopnea — by triggering a failsafe-like reflex, waking you up enough for you to breathe again. Once you resume breathing, your brain automatically tries to resume your sleep cycle.
The more severe your sleep apnea is, the more often you’ll these interruptions happen. The apnea/hypopnea index (AHI) is the average hourly number of apnea or hypopnea events — times when a person stops breathing. The AHI is the main factor determining the severity of sleep apnea. The severity is as follows:
Obstructive events, which are very short-lived, can affect any stage of sleep. They’re most common in Stage 1, Stage 2 and REM sleep. That’s why it’s common for people to not remember apnea events, which means they may not know they have a problem until the symptoms are noticeable. Central events are most common in Stages 1 and 2 of sleep but can occur during any stage.
Sleep apnea has many symptoms, some of which are easier to spot than others. The symptoms include:
Sleep apnea in children can happen in slightly different ways. The symptoms of sleep apnea in children include:
Sleep apnea usually has specific causes, and there’s evidence that it may run in families. Overall, there are three main forms of sleep apnea, with some differences in how and why they happen. The types are:
This is the more common form. Obstructive sleep apnea happens when muscles in your head and neck relax while you’re asleep, causing the surrounding tissue to press on your windpipe. That obstructs air’s ability to pass through it.
This form of sleep apnea happens because of a problem in your brain. Under ordinary circumstances, your brain manages your breathing all the time, including while you sleep. Central sleep apnea happens when your brain doesn’t send signals to keep breathing-related muscles working.
Central sleep apnea can happen for many reasons, including:
There’s also a mixed/complex type of sleep apnea. This form has a combination of both obstructive events and central events.
Diagnosing sleep apnea usually involves a healthcare provider asking questions about your symptoms and history. If they suspect sleep apnea based on your symptoms and answers, they’ll likely want you to undergo testing for sleep apnea.
The most common tests for sleep apnea include:
There are many approaches to treating sleep apnea, depending on the specific type of sleep apnea and how severe it is. While none of these is a cure, they can help prevent apnea events or reduce how often they happen or how severe they are.
Many treatments should be a part of your daily (or nightly) routine. That can ultimately reduce or even eliminate sleep apnea’s effects on your life for as long as you use these treatments.
Possible treatments include:
These nonmedical treatments or approaches can typically improve obstructive sleep apnea or resolve it. They aren’t cures, but they can reduce apnea to the point where it stops happening or isn’t severe enough to cause symptoms. These include:
Positive airway pressure is a method that uses a specialized device to increase the air pressure inside of your airway while you inhale. This method can treat obstructive, central and mixed sleep apneas.
Pushing pressurized air down your windpipe keeps it open so you can breathe. These devices push air through a hose that attaches to a special mask you wear on your face while you sleep. Masks can cover your nose, mouth or both, and there are many different types and styles to choose from.
The best-known PAP device is the Continuous Positive Airway Pressure (CPAP) machine. However, there are other types of PAP machines, too (see our CPAP Machine article for more about the different types of devices, including adaptive servo-ventilation devices). These devices increase the air pressure inside of your airway and lungs when you inhale, keeping surrounding tissue from pressing your airway shut.
Obstructive sleep apnea happens when soft tissue in your head or neck, especially around your mouth and jaw, press downward on your windpipe. Special mouthpiece devices can help hold your jaw and tongue in a position that keeps pressure off your windpipe. Dentists and sleep medicine specialists often work together to make these for people who need them.
The hypoglossal nerve (the name comes from Greek and means “under the tongue”) is what controls your tongue’s movements. A nerve stimulator attached to this nerve can stimulate it, pushing your tongue slightly forward when you breathe while you’re sleeping. That keeps your tongue from relaxing and pressing backward on your windpipe while you sleep, which is one of the ways that obstructive sleep apnea happens.
An electrode attaches to the nerve under your jaw and connects to a device implanted under the skin in your chest. You can turn the stimulator on before you sleep and turn it off after you wake up. The electrical current is strong enough to keep your tongue from relaxing too much, but mild enough that it’s not uncomfortable.
A similar kind of nerve stimulation is also possible with central sleep apnea. This type of stimulation affects the phrenic nerves. This pair of nerves connect your spinal cord to the diaphragm, a layer of muscle underneath your lungs that controls your ability to inhale and exhale. Stimulating the phrenic nerve causes those muscles to flex, helping you breathe.
Surgeries on your nose, mouth and throat can help prevent blockages of your nose, throat and windpipe. However, the impact of these in adults is usually limited and varies from person to person. These surgeries include:
In addition to positive airway pressure, adaptive ventilation and phrenic nerve stimulators, there are some medications that may help central sleep apnea. Some examples of these medications include hypnotic (sleep-promoting) medications, respiratory-stimulating drugs and more. However, none of these medications are formally approved or definitively accepted for this use.
People who have sleep apnea should avoid heavy drinking, and frequent use of sleeping pills or other drugs (recreational and otherwise) that cause heavy sedation. These can make sleep apnea worse. Your healthcare provider can talk to you about drugs that can cause that and how you can avoid the effects.
The complications and side effects of the treatments depend on many factors, especially the treatments themselves. Your healthcare provider is the best source of information for what you can do to minimize the side effects or prevent them when possible.
Sleep apnea is a condition that can severely disrupt your life and put you at risk for life-threatening complications and events (see more about these under the Outlook/Prognosis section below). Because of this, you shouldn’t try to self-diagnose or self-treat it. If you think you have sleep apnea, you should schedule an appointment with a sleep specialist or ask a primary care provider to refer you to a sleep specialist.
If you suspect you or a loved one has sleep apnea, you might be able to help a healthcare provider diagnose it. Video and audio recordings of a person sleeping, especially where the provider can hear breathing, can give a provider key evidence they need to speed up the diagnostic process.
The time it takes to recover or feel better after treatment for sleep apnea depends on the treatments themselves. Some people will feel better almost immediately, while others may need three to six months of consistent nightly treatment to see the full benefits. Your healthcare provider can tell you more about the timeline for your recovery and when you should expect to feel better.
Devices that treat sleep apnea, especially positive airway pressure devices, often bring very fast results. Older devices may take some tweaking and adjusting (a process known as “titration”) of the settings, but many newer devices can often adjust automatically to meet your needs (especially if your sleep apnea is mild or on the low end of moderate).
While some people may need to get used to wearing a mask to sleep, most people can overcome that fairly quickly. Many people see improvements immediately when they sleep through the night using a positive airway pressure device.
Sleep apnea is sometimes preventable, especially in cases where it happens because a person has excess weight or obesity. Still, some people maintain a healthy body weight or are underweight and still develop sleep apnea. For those individuals, a structural issue is usually the cause of their apnea, so they can’t prevent it.
The best things you can do to reduce your risk of sleep apnea include:
Sleep apnea is a condition that can severely disrupt your life, and it increases your risk of several conditions that are life-threatening medical emergencies. Even if it doesn’t cause these dangerous complications, people with sleep apnea can’t get restful sleep, so they constantly feel tired. In the worst cases, this condition can make them so tired that they may fall asleep during the day, leading to accidents or causing problems with work, hobbies, social activities, etc.
Sleep apnea is a dangerous condition because it can cause several different complications, many of which are severe or life-threatening. These include:
Sleep apnea is a long-term, chronic condition. For some people, it’s possible to resolve it by reducing their weight or undergoing certain treatments. For others, it may be a lifelong condition.
The outlook for sleep apnea depends on many factors. The severity and type of sleep apnea make a difference. However, adhering to treatment is usually the biggest determining factor in how this condition affects your life.
It’s critical to adhere to treatment closely. Using and sticking with treatments, especially ongoing ones like positive airway pressure devices, can make a huge difference. Many people stick with treatments like positive airway pressure devices for a month or so but then stop using them. That can increase the risk of complications and a negative outcome.
There are several key steps you can take to manage this condition:
You should go to the ER if you notice any of the symptoms of a heart attack or stroke, both of which are more likely to happen with sleep apnea.
A note from Cleveland Clinic
Sleep apnea is a widespread condition that disrupts a person’s breathing while they sleep. That causes a person to wake up just enough to breathe, interrupting their sleep and keeping them from feeling rested. Over time, sleep apnea can lead to serious or even deadly complications, so early diagnosis and treatment are vital. This condition is often very treatable and there are many treatment options.
The most common — and most effective — treatments, especially positive airway pressure devices, are meant for use every night. The best outcomes from these treatments are most likely to happen when you stick to them and make them part of your life every day without exception. If you’re struggling to stick to treatments, it’s absolutely vital that you talk to your healthcare provider. They can help you find ways to overcome these issues so you can finally get a good night’s sleep.
Last reviewed by a Cleveland Clinic medical professional on 11/15/2022.
Learn more about our editorial process.