What Causes Central Sleep Apnea?

Most people have never heard of central sleep apnea until a sleep study hands them the diagnosis. Unlike the more common obstructive sleep apnea, this type does not happen because the airway is blocked. It happens because the brain briefly stops sending the signal that tells your breathing muscles to work.

Central sleep apnea is caused by a problem in the brain’s breathing control system. The brainstem normally sends steady signals to the muscles that control breathing. In central sleep apnea, that signal becomes irregular or pauses during sleep. The airway stays open, but no effort is made to breathe. This pause is called an apnea, and it can last long enough to drop oxygen levels and pull a person briefly toward wakefulness.

That is the core answer. The rest of this article explains why the signal fails, what conditions are linked to it, and how doctors sort out the cause.

How Is Central Sleep Apnea Different From Obstructive Sleep Apnea?

The two conditions look similar on the surface. Both cause breathing to stop during sleep. Both disrupt rest. But the underlying problem is opposite in an important way.

In obstructive sleep apnea, the brain is still sending the signal to breathe. The throat tissues collapse and block the airway, so air cannot get through even though the chest and belly are still trying to move. The person is making an effort, but the effort fails.

In central sleep apnea, there is no blockage. The airway is open. The problem is that the brain is not telling the breathing muscles to move at all. During a central apnea, there is no breathing effort to measure.

This distinction matters because the treatments are different. A continuous positive airway pressure (CPAP) machine works by holding the airway open with air pressure. That solves a blockage. It does not fix a missing brain signal, so CPAP is often less effective for central sleep apnea on its own.

Some people have both types at the same time. This is called mixed sleep apnea, and it is common in certain heart and neurological conditions.

What Causes Central Sleep Apnea?

Central sleep apnea is not one disease. It is a pattern that can come from several different problems. Doctors group the causes into a few broad categories.

Cheyne-Stokes breathing

This is one of the most common patterns, especially in people with heart failure. Breathing gradually gets deeper and faster, then shallower and slower, then stops for a short pause, and the cycle repeats.

The cause is a delay in how the brain senses carbon dioxide levels in the blood. In heart failure, the heart pumps less efficiently, and blood flow to the brain and lungs is slower. That lag throws off the timing of the breathing control loop. The brain overcorrects, then undercorrects, and breathing swings back and forth.

Cheyne-Stokes breathing is strongly associated with heart failure and is a sign that the heart condition may need attention. It can also appear after a stroke.

Opioid medications

Opioids affect the part of the brainstem that controls breathing rhythm. Long-term use of these medications, including methadone and other prescription opioids, can blunt the breathing drive during sleep and cause central apneas.

This is a well-documented effect and a reason doctors monitor breathing in people on long-term opioid therapy.

High altitude

At high altitude, the air holds less oxygen. The body responds by breathing more, which lowers carbon dioxide levels in the blood. Low carbon dioxide can itself suppress the breathing drive, creating a cycle of overbreathing followed by pauses. This usually improves after returning to lower altitude or after a period of acclimation.

Brainstem and neurological conditions

The breathing control center sits in the brainstem. Anything that damages it can cause central sleep apnea. This includes stroke, certain neurodegenerative diseases, and other conditions that affect the brainstem. These causes are less common but important to identify.

Idiopathic central sleep apnea

Sometimes no clear cause is found. This is called idiopathic central sleep apnea. It is diagnosed when other causes have been ruled out.

What Conditions Are Linked to Central Sleep Apnea?

Central sleep apnea rarely appears on its own. It often shows up alongside another health problem, and finding that problem is a key part of treatment.

• Heart failure — the most common and best-studied link, often through Cheyne-Stokes breathing.
• Atrial fibrillation and other heart rhythm problems — sleep-related breathing problems and irregular heart rhythms frequently occur together.
• Stroke — damage to brain areas that control breathing can trigger central apneas.
• Chronic kidney disease — changes in blood chemistry can affect breathing control.
• Long-term opioid use — a direct effect on the brainstem’s breathing rhythm.
• Neuromuscular and neurodegenerative disorders — conditions that affect the nerves and muscles of breathing.

The relationship often runs in both directions. Heart failure can cause central sleep apnea, and central sleep apnea can make heart failure harder to manage. Treating one can affect the other.

What Are the Symptoms of Central Sleep Apnea?

The symptoms overlap heavily with obstructive sleep apnea, so they alone cannot tell the two apart. A sleep study is needed to do that.

Common symptoms include:

• Waking up frequently during the night
• Daytime sleepiness and low energy
• Morning headaches
• Poor concentration and memory
• Shortness of breath that improves when sitting up
• Witnessed pauses in breathing by a bed partner
• Insomnia, especially waking suddenly with a gasp or feeling short of breath

One pattern worth knowing: people with central sleep apnea often report insomnia and sudden nighttime awakenings more than loud snoring. Snoring is more typical of obstructive sleep apnea. That said, snoring can happen in either type, so it is not a reliable way to tell them apart.

Some people have central apneas that cause no obvious symptoms at all and are found only during a sleep study done for another reason.

How Is Central Sleep Apnea Diagnosed?

Diagnosis requires a sleep study, also called a polysomnogram. This test records breathing effort, airflow, oxygen levels, brain waves, heart rhythm, and muscle activity during sleep.

The key measurement is breathing effort. In a central apnea, airflow stops but there is no effort to breathe. In an obstructive apnea, airflow stops but the chest and belly are still working to pull air in. This difference is what separates the two on the test.

Doctors also look at how often apneas and shallow-breathing events happen per hour of sleep. This number, called the apnea-hypopnea index, helps grade how severe the condition is. The pattern of events across the night can also point toward a specific cause, such as Cheyne-Stokes breathing.

Because central sleep apnea is so often tied to another condition, diagnosis usually includes a heart evaluation and a review of medications. Finding the underlying cause is not optional — it shapes the entire treatment plan.

How Is Central Sleep Apnea Treated?

Treatment starts with the cause, not the breathing pattern. This is the single most important point about central sleep apnea, and it is where it differs most from obstructive sleep apnea.

When an underlying condition is found, treating it often improves the breathing problem. Managing heart failure more effectively, adjusting opioid medications with a doctor’s guidance, or addressing a neurological issue can all reduce central apneas.

For the breathing pattern itself, options include:

• Positive airway pressure therapy — CPAP or a related machine. It works better for some causes than others and is often less effective for central sleep apnea than for obstructive sleep apnea.
• Adaptive servo-ventilation (ASV) — a machine that adjusts pressure breath by breath to steady the breathing pattern. It is used for certain types of central sleep apnea, particularly Cheyne-Stokes breathing. Its use in people with a specific type of heart failure has been an area of ongoing research and caution, so eligibility is decided carefully by a specialist.
• Supplemental oxygen — sometimes used to keep oxygen levels steady.
• Medication review — reducing or changing opioids when medically appropriate, always with a doctor’s supervision.

No single treatment works for everyone, and the right choice depends on the cause. This is genuinely a condition where a sleep specialist and, often, a cardiologist should be involved.

When Should You Talk to a Doctor?

Talk to a doctor if you have witnessed pauses in your breathing during sleep, wake up gasping, feel exhausted despite enough time in bed, or have heart failure and notice your sleep getting worse.

Central sleep apnea is not something to self-diagnose or self-treat. The causes range from manageable to serious, and the treatment depends entirely on which one applies to you. If you already have heart failure, a stroke history, or long-term opioid use, it is worth raising sleep symptoms with your doctor directly.

Untreated sleep-related breathing problems can strain the heart and worsen daytime function. Getting evaluated is a reasonable and low-risk step.