Central Sleep Apnea

What central sleep apnea is

Central sleep apnea (CSA) is a form of sleep apnea in which the brain briefly fails to send the signal that tells your breathing muscles to work. For seconds at a time during sleep, the drive to breathe simply pauses — and because there is no signal, there is no effort to breathe at all. It is far less common than the obstructive kind, and it usually points to something else going on in the body.

That "no effort" detail is what separates CSA from the apnea most people have heard of. In obstructive sleep apnea (OSA), the airway physically collapses and you strain to breathe against the blockage — the effort is there, the air just cannot get through. In central sleep apnea, the airway is open, but the command to breathe momentarily does not come. Same end result — interrupted breathing and fragmented sleep — but a fundamentally different mechanism, which is why it is diagnosed and treated differently.

Central sleep apnea is most often secondary — that is, it arises as a consequence of another condition rather than on its own. Heart failure, stroke, certain medications, and high altitude are the common drivers. Because of that, finding central apnea on a sleep study is often a clue that prompts a closer look at the heart, the nervous system, or a medication list, as much as it is a diagnosis in its own right.

Central vs obstructive: the key difference

The two forms of sleep apnea share a name and a consequence, but they are mechanically opposite problems, and the distinction drives everything that follows — testing, treatment, and what the diagnosis means for the rest of your health.

One practical implication: because the difference between a central and an obstructive event comes down to whether breathing effort is present, distinguishing them reliably requires the detailed monitoring of an in-lab sleep study, which records respiratory effort directly. This is one of the situations where a home test is not enough.

What causes it

Because central sleep apnea is usually secondary to another condition, understanding the cause is most of understanding the disorder. The common drivers:

• Heart failure. This is the most important association. A specific pattern of central apnea — a smooth crescendo-decrescendo cycle of breathing called Cheyne-Stokes respiration — is characteristic of heart failure, and its presence carries prognostic weight. Central apnea and heart failure influence each other, which is why the two are managed together.
• Stroke and neurological conditions. Because breathing rhythm is generated in the brainstem, strokes and other neurological conditions affecting those control centers can disrupt the signal to breathe.
• Long-term opioid use. Opioid medications suppress the brain's respiratory drive, and chronic use is a recognized cause of central sleep apnea. This is one reason a medication review is part of the workup.
• High altitude. At altitude, the lower oxygen level changes breathing control and can produce central apneas in otherwise healthy people — usually resolving on return to lower elevation.

There is also a less common primary (idiopathic) form, where no underlying cause is found, and a "treatment-emergent" form that can appear when obstructive apnea is treated with CPAP. In all of these, identifying which kind you have shapes the treatment.

The heart-failure connection deserves a closer look, because it is both the most common and the most clinically meaningful. In advanced heart failure, the body's control of breathing becomes unstable, producing the smooth rise-and-fall cycle of Cheyne-Stokes respiration: breathing gradually deepens, then gradually fades to a pause, then repeats, over and over through the night. This pattern is not just a curiosity — its presence is associated with the severity of the heart condition and carries prognostic weight, which is why its discovery on a sleep study prompts close coordination with cardiology. The relationship runs both ways: the heart failure destabilizes breathing, and the resulting nighttime stress on the cardiovascular system can in turn burden the heart, a loop that treating both sides aims to interrupt.

The treatment-emergent form is worth understanding too, because it can surprise people. In some patients who start CPAP for obstructive apnea, central apneas appear or become more prominent once the airway obstruction is relieved. In many cases this settles with time as the body adapts; in others it requires a change in approach. It is a recognized phenomenon rather than a sign that treatment has failed, and a sleep specialist monitors for it.

Signs and symptoms

The symptoms of central sleep apnea overlap with the obstructive kind — fragmented, unrefreshing sleep and daytime tiredness — but there are some distinguishing clues.

Witnessed breathing pauses are common, but unlike obstructive apnea, they often occur without loud snoring, because there is no struggle against a blocked airway to produce the noise. A bed partner may describe pauses followed by a return of breathing, sometimes in a rhythmic waxing-and-waning pattern. People with CSA frequently report waking abruptly short of breath, difficulty staying asleep, and the daytime fatigue, poor concentration, and morning headaches that any sleep-disordered breathing can cause.

Because so many cases are tied to heart failure, stroke, or opioid use, central sleep apnea is sometimes first suspected not from the sleep symptoms themselves but in the course of managing one of those conditions — which is part of why anyone with significant heart or neurological disease and poor, broken sleep is worth evaluating.

How it's diagnosed

Central sleep apnea is diagnosed with an in-lab sleep study (polysomnography). This matters: while obstructive apnea can often be confirmed with a home sleep apnea test, distinguishing central from obstructive events requires measuring whether you are making an effort to breathe during each pause — and the belts and sensors that record respiratory effort directly are part of the in-lab setup, not most home tests.

The study counts how many apneas and hypopneas occur per hour (the apnea-hypopnea index) and, crucially, classifies them as central or obstructive based on the presence or absence of breathing effort. It can also detect the characteristic Cheyne-Stokes pattern associated with heart failure. Because central apnea is so often secondary, the evaluation usually extends beyond the sleep study to the underlying cause — assessment of heart function, review of medications, and neurological history as appropriate.

How it's treated

Treating central sleep apnea has two parts: addressing the underlying cause, and supporting breathing during sleep. The balance between them depends on what is driving the apnea.

Treat the underlying condition. Because CSA is usually secondary, optimizing the root cause is often the most important step — for example, improving heart failure management, or reviewing and adjusting opioid medications with the prescribing clinician. In altitude-related cases, the apnea typically resolves on its own at lower elevation. In many people, addressing the cause meaningfully reduces the central apnea.

Support breathing during sleep. Positive airway pressure therapy is used, but differently than in obstructive apnea — the standard fixed-pressure CPAP that splints open an airway is not always the right tool when the problem is an absent signal rather than a blockage. Specialized PAP modes, including adaptive servo-ventilation in selected patients, are designed to respond to the irregular breathing pattern of central apnea. Importantly, the choice of therapy depends on the underlying condition, and some modes are not appropriate for certain patients with heart failure — which is exactly why central sleep apnea is managed by a sleep specialist in coordination with cardiology or neurology rather than treated with a one-size-fits-all device. Supplemental oxygen is used in selected cases.

The through-line is that central sleep apnea is rarely a standalone problem with a standalone fix. It is treated in the context of the condition that produced it, by a team rather than a single device.

It is also worth being realistic about the goal. For central apnea driven by a chronic condition like heart failure, the aim is usually good control and improved sleep and daytime function, managed over time, rather than a one-and-done cure — much as the underlying condition itself is managed long-term. For reversible causes, the outlook is better: altitude-related central apnea resolves on descent, opioid-related apnea can improve substantially when medications are adjusted, and treatment-emergent central apnea often settles. What ties the good outcomes together is the same theme as the rest of the page — the central apnea tends to follow the underlying cause, so the more treatable the cause, the more treatable the apnea.

Living with central sleep apnea

Because central sleep apnea is managed alongside an underlying condition, living with it usually means folding sleep care into the broader care you are already receiving rather than treating it as a separate project. For someone with heart failure, for example, the sleep specialist and cardiologist coordinate, and improvements in heart management and in the apnea tend to reinforce each other. The practical experience for many people is a set of regular follow-ups, periodic reassessment of how well breathing is supported during sleep, and adjustments over time as the underlying condition evolves.

Adherence to whatever breathing support is prescribed matters here just as it does in obstructive apnea, and the same principle applies: a therapy only helps if it is used consistently. If a particular device or mode is uncomfortable or not working, that is information to bring back to the specialist rather than a reason to quietly stop — central apnea has more than one therapeutic option, and finding the right fit can take iteration. The encouraging reality is that effective management of the apnea often improves not just sleep quality and daytime energy but also contributes to the stability of the underlying condition, which is why getting it right is worth the follow-up effort.

It is also reasonable to expect the picture to change over time. As the underlying condition is treated, the central apnea may lessen; as it progresses, the apnea may need a different approach. This is not a sign of failure but the normal course of a condition that tracks its cause — and it is precisely why ongoing specialist involvement, rather than a one-time fix, is the model of care.

When to talk to your doctor

If a bed partner has noticed you stop breathing in your sleep — particularly without the loud snoring typical of obstructive apnea — or if you wake abruptly short of breath, it is worth raising with your doctor. This is especially important if you have heart failure, have had a stroke, take long-term opioid medication, or have another significant heart or neurological condition, because central sleep apnea is both more likely and more consequential in those settings.

Central sleep apnea is not something to self-diagnose or self-treat, and it is not a condition an over-the-counter device addresses. The right step is an evaluation by a sleep specialist, who can arrange the in-lab study needed to distinguish it from obstructive apnea and coordinate with your other doctors on the underlying cause. If you are not sure where to start, the free Sleep Score screener can help you gauge your overall apnea risk and point you toward an evaluation — though the definitive distinction between central and obstructive apnea is made in the sleep lab.