What is central sleep apnea?
Breathing is controlled automatically by the brainstem, which sends signals to the diaphragm and chest muscles. In central sleep apnea, this signal temporarily stops or becomes unstable, so breathing pauses for 10 seconds or more, with no effort to breathe. Oxygen drops, the brain briefly wakes you to restart breathing and sleep becomes fragmented, often without you remembering. See snoring remedies and mandibular advancement device for obstructive problems.
Central versus obstructive sleep apnea
- Obstructive (OSA): the airway collapses; there is chest effort against a blocked airway; loud snoring and gasping are typical; linked with obesity, a large neck and airway anatomy; treated with CPAP, oral devices, weight loss and sometimes surgery.
- Central (CSA): no effort to breathe; snoring may be mild or absent; linked with heart failure, stroke, opioids and altitude.
- Mixed or complex sleep apnea: central apneas appear when CPAP is started for OSA (treatment-emergent CSA).
- A sleep study distinguishes them. Treatments differ, so the correct diagnosis matters.
Symptoms
- Observed pauses in breathing during sleep, noticed by a partner.
- Waking suddenly with shortness of breath.
- Difficulty falling or staying asleep (insomnia).
- Morning headaches and dry mouth.
- Excessive daytime sleepiness and fatigue.
- Poor concentration, mood changes and irritability.
- Snoring (may be present but is often less obvious than in OSA).
- Swelling in the legs, breathlessness or palpitations if heart failure is present.
Causes and risk factors
- Heart failure with Cheyne–Stokes breathing, a waxing and waning pattern.
- Atrial fibrillation and other heart disease.
- Stroke, brain tumour, brainstem injury or neurological disease affecting breathing control.
- Opioid medicines (morphine, methadone, oxycodone) and some other sedatives.
- High-altitude periodic breathing.
- Kidney failure.
- Treatment-emergent central sleep apnea after starting CPAP.
- Male sex, age over 65 and low carbon-dioxide levels.
- Idiopathic central sleep apnea, with no cause found.
How it is diagnosed
- History and sleep questionnaires such as the Epworth Sleepiness Scale.
- Assessment of heart, brain, kidney and medicines.
- Overnight polysomnography (a sleep lab test) measuring breathing effort, oxygen, heart rhythm, brain waves and airflow.
- Home sleep apnea tests may not distinguish central events reliably.
- Blood tests, heart scans (echocardiogram), neurological imaging as needed.
- Referral to a sleep specialist, cardiologist or neurologist.
Treatment
- Treat the underlying cause: optimise heart failure therapy, review opioids, treat stroke recovery, descend from altitude.
- CPAP or bilevel positive airway pressure can help some patients, particularly with mixed apnea.
- Adaptive servo-ventilation (ASV): adjusts pressure to your breathing; used selectively and contraindicated in people with symptomatic heart failure and a reduced ejection fraction (LVEF 45% or lower).
- Supplemental oxygen at night in selected patients.
- Acetazolamide and, in some centres, other medicines to stabilise breathing, as prescribed.
- Phrenic nerve stimulation (an implanted device) for selected patients.
- Lifestyle: avoid alcohol and sedatives, avoid sleeping on your back if it worsens events, treat nasal obstruction.
- Treatment is tailored by a sleep specialist after the sleep study.
Why treatment matters
Untreated sleep apnea fragments sleep, causes daytime sleepiness and raises the risk of accidents, high blood pressure, arrhythmias, heart failure progression and stroke. In heart failure, central apnea is a marker of worse outcomes. Treating sleep apnea improves energy, mood and concentration, and may help heart function in selected patients.
What you can do
- Keep a regular sleep schedule and avoid alcohol and sedatives in the evening.
- Do not drive or operate machinery if sleepy.
- Tell your doctor about all medicines, particularly opioids and sleeping pills.
- Sleep with your head raised or on your side if advised.
- Treat nasal congestion. See blocked nose at night.
- Maintain a healthy weight and exercise as advised.
- Use prescribed devices nightly and attend follow-ups.
When to see a doctor
- Breathing pauses witnessed during sleep.
- Daytime sleepiness, morning headaches or waking breathless.
- Sleep apnea symptoms with heart failure, atrial fibrillation or stroke.
- New symptoms after starting CPAP or opioid medicines.
- Chest pain, severe breathlessness or fainting: urgent.
- Falling asleep while driving.
- Children with pauses in breathing or noisy sleep.
Three common situations
A man with heart failure who wakes breathless and has periodic breathing: needs sleep study and heart review.
A person on long-term opioids with pauses in breathing: medicine review and specialist assessment.
A person with OSA whose central events appear on CPAP: the sleep specialist can adjust therapy.
Key points to remember
Central sleep apnea is a failure of breathing drive during sleep, often linked to heart, brain or medicine problems. A sleep study confirms it; treatment targets the cause and may include pressure devices, oxygen or other options. Seek assessment for breathing pauses and daytime sleepiness. Our ENT team can screen for sleep-disordered breathing.
This guide is for general information and does not replace an examination by your own doctor or ENT specialist.
Questions about central sleep apnea
These answers are general information and do not replace an examination or individual medical advice.
What causes central sleep apnea?
Heart failure, stroke, opioid medicines, high altitude, kidney failure and sometimes no clear cause.
How is it different from obstructive sleep apnea?
In central apnea there is no effort to breathe because the brain does not send the signal; in obstructive apnea the airway is blocked.
How is central sleep apnea diagnosed?
With an overnight sleep study (polysomnography).
Can CPAP treat it?
It helps some patients, but others need adaptive servo-ventilation, oxygen or other therapies.
Is central sleep apnea serious?
It can be, especially in heart failure, so it needs assessment and treatment.
Does snoring mean central sleep apnea?
Not necessarily; snoring is more typical of obstructive apnea.
Sources
This guide is for general information and does not replace medical advice. How a problem is diagnosed and treated depends on your examination and medical history. If you think you have an emergency, contact your local emergency services.