What is central sleep apnea

Central sleep apnea is a disorder in which your breathing repeatedly stops and starts during sleep. Central sleep apnea occurs because your brain doesn’t send proper signals to the muscles that control your breathing. A single central apnea event is a ≥10-second pause in breathing with no associated respiratory effort; greater than five such events per hour are considered abnormal. Central sleep apnea is present when a patient has greater than five central apneas per hour of sleep with associated symptoms of disrupted sleep (such as excessive daytime somnolence). Central sleep apnea is different from obstructive sleep apnea, in which you can’t breathe normally because of upper airway obstruction. Central sleep apnea is less common than obstructive sleep apnea. As opposed to obstructive sleep apnea (OSA), central sleep apnea is characterized by repetitive cessation of breathing during sleep resulting from lack of ventilatory effort or drive to breathe from your brain.

Central sleep apnea may occur as a result of other conditions, such as heart failure and stroke. Sleeping at a high altitude also may cause central sleep apnea.

Treatments for central sleep apnea involve treating existing condition that is causing central sleep apnea, using a device to assist breathing or using supplemental oxygen. Oxygen treatment may help ensure the lungs get enough oxygen while sleeping. Devices used during sleep to aid breathing may be recommended. These include nasal continuous positive airway pressure (CPAP), bilevel positive airway pressure (BiPAP) or adaptive servo-ventilation (ASV). Some types of central sleep apnea are treated with medicines that stimulate breathing. If narcotic medicine is causing the apnea, the dosage may need to be lowered or the medicine changed.

Can you die from central sleep apnea?

It depends on what is causing your central sleep apnea. Central sleep apnea is most commonly associated with congestive heart failure or stroke. Central sleep apnea can also be due to end stage kidney disease, in people who have a problem with an area of the brain called the brainstem, which controls breathing or in people taking taking certain medications such as opioids, see central sleep apnea causes below for more details. In addition, sudden drops in blood oxygen levels (hypoxemia) that occur during central sleep apnea may adversely affect your heart health. If you have an underlying heart disease, these repeated multiple episodes of low blood oxygen (hypoxia or hypoxemia) worsen prognosis and increase the risk of abnormal heart rhythms (arrhythmias).

Untreated sleep apnea may lead to or worsen heart disease, including:

• Heart arrhythmias
• Heart failure
• Heart attack
• High blood pressure
• Stroke

Central vs Obstructive sleep apnea

Obstructive sleep apnea (OSA) is a problem in which your breathing pauses during sleep because of narrowed or blocked airways. On the other hand, central sleep apnea is characterized by repetitive cessation of breathing during sleep resulting from the brain temporarily stops sending signals to the muscles that control breathing. Whereas obstructive sleep apnea (OSA) is extremely common in the adult population, central sleep apnea affects less than 10% of patients referred to sleep laboratories. However, central apneas also may occur in an individual with obstructive apneas, a person can have both conditions, such as with a medical problem called obesity hypoventilation syndrome (OHS). Clinicians may struggle to determine if central sleep apnea or obstructive sleep apnea (OSA) is the principal problem, or if a combination of the 2 disorders may need therapy. Obesity hypoventilation syndrome is a condition in some obese people in which poor breathing leads to lower oxygen and higher carbon dioxide levels in the blood. The exact cause of obesity hypoventilation syndrome is not known. Researchers believe obesity hypoventilation syndrome (OHS) results from a defect in the brain’s control over breathing. Excess weight against the chest wall also makes it harder for the muscles to draw in a deep breath and to breathe quickly enough. As a result, the blood contains too much carbon dioxide and not enough oxygen. Untreated, obesity hypoventilation syndrome (OHS) can lead to serious heart and blood vessel problems, severe disability, or death.

Treatment for obesity hypoventilation syndrome (OHS) involves breathing assistance using special machines (mechanical ventilation). Options include:

• Noninvasive mechanical ventilation such as continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BPAP) through a mask that fits tightly over the nose or nose and mouth (mainly for sleep)
• Oxygen therapy
• Breathing help through an opening in the neck (tracheostomy) for severe cases
• Other treatments are aimed at weight loss, which can reverse obesity hypoventilation syndrome (OHS).

Treatment is started in the hospital or as an outpatient.

Obstructive sleep apnea causes

When you sleep, all of the muscles in your body become more relaxed. This includes the muscles that help keep your throat open so air can flow into your lungs.

Normally, your throat remains open enough during sleep to let air pass by. Some people have a narrow throat. When the muscles in their upper throat relax during sleep, the tissues close in and block the airway. This stop in breathing is called apnea.

Loud snoring is a telltale symptom of obstructive sleep apnea. Snoring is caused by air squeezing through the narrowed or blocked airway. Not everyone who snores has sleep apnea though.

Other factors also may increase your risk of obstructive sleep apnea:

• A lower jaw that is short compared to your upper jaw
• Certain shapes of the roof of your mouth (palate) or airway that cause it to collapse more easily
• Large neck or collar size, 17 inches (43 centimeters) or more in men and 16 inches (41 centimeters) or more in women
• Large tongue, which may fall back and block the airway
• Obesity
• Large tonsils and adenoids that can block the airway

Sleeping on your back can also cause your airway to become blocked or narrowed.

Obstructive sleep apnea symptoms

If you have obstructive sleep apnea, you usually begin snoring heavily soon after falling asleep.

• The snoring often becomes very loud.
• Snoring is interrupted by a long silent period while your breathing stops.
• The silence is followed by a loud snort and gasp, as you attempt to breathe.
• This pattern repeats throughout the night.

Most people with obstructive sleep apnea do not know their breathing starts and stops during the night. Usually, a sleep partner or other family members hear the loud snoring, gasping, and snorting. Snoring can be loud enough to hear through walls. Sometimes, people with obstructive sleep apnea wake up gasping for air.

People with sleep apnea may:

• Wake up unrefreshed in the morning
• Feel sleepy or drowsy throughout the day
• Act grumpy, impatient, or irritable
• Be forgetful
• Fall asleep while working, reading, or watching TV
• Feel sleepy while driving or even fall asleep while driving
• Have hard-to-treat headaches

Other problems that may occur include:

• Depression
• Hyperactive behavior, especially in children
• Difficult to treat high blood pressure
• Leg swelling (if apnea is severe)

Obstructive sleep apnea possible complications

Untreated obstructive sleep apnea may lead to or worsen heart disease, including:

• Heart arrhythmias
• Heart failure
• Heart attack
• High blood pressure
• Stroke

Obstructive sleep apnea treatment

Treatment helps keep your airway open while you sleep so your breathing does not stop.

Lifestyle changes may help relieve symptoms in people with mild sleep apnea, such as:

• Avoid alcohol or medicines that make you sleepy before bedtime. They can make symptoms worse.
• Avoid sleeping on your back.
• Lose excess weight.

Continuous positive airway pressure (CPAP) devices work best to treat obstructive sleep apnea in most people.

• You wear a mask over your nose or over your nose and mouth while you sleep.
• The mask is connected by a hose to a small machine that sits at the side of your bed.
• The machine pumps air under pressure through the hose and mask and into your airway while you sleep. This helps keep your airway open.

It can take some time to get used to sleeping with continuous positive airway pressure (CPAP) therapy. Good follow-up and support from a sleep center can help you overcome any problems using CPAP.

Dental devices may help some people. You wear them in your mouth while you sleep to keep your jaw forward and the airway open.

Other treatments may be available, but there is less evidence that they work. It is best to talk with a doctor who specializes in sleep problems before trying them.

Surgery may be an option for some people. It is often a last resort if other treatments did not work and you have severe symptoms. Surgery may be used to:

• Remove extra tissue at the back of the throat.
• Correct problems with the structures in the face.
• Create an opening in the windpipe to bypass the blocked airway if there are physical problems.
• Remove the tonsils and adenoids.

Surgery may not completely cure obstructive sleep apnea and may have long-term side effects.

Obstructive sleep apnea prognosis

If not treated, sleep apnea may cause:

• Anxiety and depression
• Loss of interest in sex
• Poor performance at work or school

Daytime sleepiness because of sleep apnea can increase the risk of:

• Motor vehicle accidents from driving while sleepy
• Industrial accidents from falling asleep on the job

In most cases, treatment completely relieves symptoms and problems from sleep apnea.

Central sleep apnea causes

Central sleep apnea occurs when your brain fails to transmit signals to your breathing muscles.

Central sleep apnea can be caused by a number of conditions that affect the ability of your brainstem — which links your brain to your spinal cord and controls many functions such as heart rate and breathing — to control your breathing. Problems that affect your brainstem, including brain infection, stroke, or conditions of the cervical spine (neck).

The cause varies with the type of central sleep apnea you have. Types include:

• Cheyne-Stokes breathing. Cheyne-Stokes breathing pattern involves alternating deep and heavy breathing with shallow, or even not breathing, usually while sleeping. Cheyne-Stokes breathing is characterized by a gradual increase and then decrease in breathing effort and airflow. During the weakest breathing effort, a total lack of airflow (central sleep apnea) can occur. This type of central sleep apnea is most commonly associated with congestive heart failure or stroke.
• Drug-induced apnea. Taking certain medications such as opioids — including morphine (Ms Contin, Kadian, others), oxycodone (Roxicodone, Oxycontin, others) or codeine — may cause your breathing to become irregular, to increase and decrease in a regular pattern, or to temporarily stop completely.
• High-altitude periodic breathing. A Cheyne-Stokes breathing pattern may occur if you’re exposed to a very high altitude. The change in oxygen at this altitude is the reason for the alternating rapid breathing (hyperventilation) and underbreathing.
• Treatment-emergent central sleep apnea. Some people with obstructive sleep apnea (OSA) develop central sleep apnea while using continuous positive airway pressure (CPAP) for their sleep apnea treatment. This condition is known as treatment-emergent central sleep apnea and is a combination of obstructive and central sleep apneas.
• Medical condition-induced central sleep apnea. Several medical conditions, including end-stage kidney disease and stroke, may give rise to central sleep apnea of the non-Cheyne-Stokes variety.
• Severe obesity
• Idiopathic (primary) central sleep apnea. The cause of this uncommon type of central sleep apnea isn’t known.

Risk factors for central sleep apnea

Certain factors put you at increased risk of central sleep apnea:

• Sex. Males are more likely to develop central sleep apnea than are females.
• Age. Central sleep apnea is more common among older adults, especially adults older than age 65, possibly because they may have other medical conditions or sleep patterns that are more likely to cause central sleep apnea.
• Heart disorders. People with irregular heartbeats (atrial fibrillation) or whose heart muscles don’t pump enough blood for the body’s needs (congestive heart failure) are at greater risk of central sleep apnea.
• Stroke, brain tumor or a structural brainstem lesion. These brain conditions can impair the brain’s ability to regulate breathing.
• High altitude. Sleeping at an altitude higher than you’re accustomed to may increase your risk of sleep apnea. High-altitude sleep apnea is no longer a problem a few weeks after returning to a lower altitude.
• Opioid use. Opioid medications may increase the risk of central sleep apnea.
• CPAP. Some people with obstructive sleep apnea develop central sleep apnea while using continuous positive airway pressure (CPAP). This condition is known as treatment-emergent central sleep apnea. It is a combination of obstructive and central sleep apneas. For most people, treatment-emergent central sleep apnea goes away with continued use of a continuous positive airway pressure (CPAP) device. Other people may be treated with a different kind of positive airway pressure therapy.

Central sleep apnea symptoms

Central sleep apnea common signs and symptoms include:

• Observed episodes of stopped breathing or abnormal breathing patterns during sleep
• Abrupt awakenings accompanied by shortness of breath
• Shortness of breath that’s relieved by sitting up
• Difficulty staying asleep (insomnia)
• Excessive daytime sleepiness (hypersomnia)
• Chest pain at night
• Difficulty concentrating
• Mood changes
• Morning headaches
• Snoring
• Lower tolerance for exercise

Other symptoms may include:

• Chronic fatigue
• Daytime sleepiness
• Morning headaches
• Restless sleep

Other symptoms may occur if the apnea is due to a problem with the nervous system. Symptoms depend on the parts of the nervous system that are affected, and may include:

• Shortness of breath
• Swallowing problems
• Voice changes
• Weakness or numbness throughout the body

Although snoring indicates some degree of airflow obstruction, snoring also may be heard in the presence of central sleep apnea. However, snoring may not be as prominent with central sleep apnea as it is with obstructive sleep apnea.

Central sleep apnea complications

Central sleep apnea is a serious medical condition. Some complications include:

• Fatigue. The repeated awakenings associated with sleep apnea make normal, restorative sleep impossible. People with central sleep apnea often experience severe fatigue, daytime drowsiness and irritability. You may have difficulty concentrating and find yourself falling asleep at work, while watching television or even when driving.
• Cardiovascular problems. In addition, sudden drops in blood oxygen levels that occur during central sleep apnea may adversely affect heart health. If there’s underlying heart disease, these repeated multiple episodes of low blood oxygen (hypoxia or hypoxemia) worsen prognosis and increase the risk of abnormal heart rhythms.

Central sleep apnea diagnosis

Your doctor may make an evaluation based on your signs and symptoms or may refer you to a sleep specialist in a sleep disorder center.

Your doctor will take your medical history and do a physical exam.

• Your doctor will check your mouth, neck, and throat.
• You may be asked about daytime sleepiness, how well you sleep, and bedtime habits.

You will need to have a sleep study or polysomnography to confirm central sleep apnea. This testing can be done in your home or in a sleep lab.

Other tests that may be performed include:

• Arterial blood gases
• Electrocardiogram (ECG)
• Echocardiogram
• Thyroid function studies
• Lung function testing
• MRI of the brain, spine, or neck

A sleep specialist can help you decide on your need for further evaluation. Such an evaluation often involves overnight monitoring of your breathing and other body functions during a sleep study called polysomnography.

During polysomnography, you’re connected to equipment that monitors your heart, lung and brain activity, breathing patterns, arm and leg movements, and blood oxygen levels while you sleep. You may have a full-night or split-night sleep study.

In a split-night sleep study, you’re monitored during the first half of the night. If you’re diagnosed with central sleep apnea, staff may wake you and give you positive airway pressure for the second half of the night.

Polysomnography can help your doctor diagnose central sleep apnea. It also can help your doctor rule out other sleep disorders, such as obstructive sleep apnea, repetitive movements during sleep (periodic limb movements) or sudden attacks of sleep (narcolepsy), which can cause excessive daytime sleepiness but require different treatment.

Doctors trained in nervous system diseases (neurologists), heart diseases (cardiologists) and others may be involved in evaluating your condition. Doctors may also order imaging of your head or heart to look for contributing conditions.

Central sleep apnea treatment

Central sleep apnea treatments may include:

• Addressing associated medical problems. Possible causes of central sleep apnea include other disorders, and treating those conditions may help your central sleep apnea. For example, if central sleep apnea is due to heart failure, the goal is to treat the heart failure itself.
• Reduction of opioid medications. If opioid medications are causing your central sleep apnea, your doctor may gradually reduce your dose of those medications.
• Continuous positive airway pressure (CPAP). This method, also used to treat obstructive sleep apnea, involves wearing a mask over your nose or your nose and mouth while you sleep. CPAP is usually the first treatment given for central sleep apnea. The mask is attached to a small pump that supplies a continuous amount of pressurized air to hold open your upper airway. CPAP may prevent the airway closure that can trigger central sleep apnea. As with obstructive sleep apnea, it’s important that you use the device only as directed. If your mask is uncomfortable or the pressure feels too strong, talk with your doctor. Several types of masks are available. Doctors can also adjust the air pressure.
• Adaptive servo-ventilation. If CPAP hasn’t effectively treated your condition, you may be given adaptive servo-ventilation. Like CPAP, adaptive servo-ventilation also delivers pressurized air. Unlike CPAP, adaptive servo-ventilation adjusts the amount of pressure during inhalation on a breath-by-breath basis to smooth out the breathing pattern. The device may also automatically deliver a breath if you haven’t taken a breath within a certain number of seconds. Adaptive servo-ventilation isn’t recommended for people with symptomatic heart failure.
• Bilevel positive airway pressure (BPAP). Like adaptive servo-ventilation, bilevel positive airway pressure (BPAP) delivers pressure when you breathe in and a different amount of pressure when you breathe out. Unlike adaptive servo-ventilation, the amount of pressure during inspiration is fixed rather than variable. Bilevel positive airway pressure (BPAP) can also be configured to deliver a breath if you haven’t taken a breath within a certain number of seconds. BPAP could worsen central sleep apnea in people with heart failure. Be sure to talk to your doctor about the potential risks of BPAP if your doctor is considering this therapy and you have heart failure.
• Supplemental oxygen. Using supplemental oxygen while you sleep may help if you have central sleep apnea. Various devices are available to deliver oxygen to your lungs.
• Medications. Certain medications, such as acetazolamide (Diamox) or theophylline (Theo-24, Theochron), have been used to stimulate breathing in people with central sleep apnea. These medications may be prescribed to help your breathing as you sleep if you can’t tolerate positive airway pressure. These medications may also be used to prevent central sleep apnea in high altitude.

Surgery or other procedures

A new therapy for people with symptomatic heart failure who have moderate to severe sleep apnea involves stimulation of the nerve that runs from the brain to the diaphragm (transvenous phrenic nerve stimulation). A nerve stimulator, which is implanted in your chest, acts like a pacemaker to help you breathe normally during sleep. The device monitors your breathing and stimulates the phrenic nerve to generate a breath if you’ve gone too long without breathing during sleep.

Central sleep apnea prognosis

How well you do depends on the medical condition causing central sleep apnea. The prognosis is usually favorable for people with idiopathic central sleep apnea.

If not treated, central sleep apnea may cause:

• Anxiety and depression
• Loss of interest in sex
• Poor performance at work or school

Daytime sleepiness because of central sleep apnea can increase the risk of:

• Motor vehicle accidents from driving while sleepy
• Industrial accidents from falling asleep on the job.