Sleep Apnoea Without Snoring: Signs and Treatment

Sleep apnoea without snoring is more common than many people realise, yet the absence of loud snoring often means the condition goes undetected for years. Obstructive sleep apnoea (OSA) and central sleep apnoea (CSA) can both occur silently, causing repeated breathing pauses during sleep without the characteristic noise most people associate with the condition. Symptoms such as excessive daytime sleepiness, unrefreshing sleep and morning headaches may be the only clues. This article explains who is at risk, how silent sleep apnoea is diagnosed in the UK, and when to seek medical advice.

Can you have sleep apnoea without snoring?

Yes, sleep apnoea can occur without snoring in both obstructive and central forms, as the airway may narrow silently or breathing signals may fail without producing audible noise.

Yes, it is entirely possible to have sleep apnoea without snoring, and many people with the condition are unaware of it precisely because they assume snoring is a necessary symptom. Obstructive sleep apnoea (OSA) occurs when the upper airway repeatedly collapses during sleep, causing breathing to pause for ten seconds or longer.^[1][8] While snoring is common in OSA, it is not universal. Some people experience these breathing pauses silently, particularly if the airway narrows rather than vibrates, or if they sleep in positions that reduce airway noise.

Central sleep apnoea (CSA) is another form of the condition in which the brain fails to send the correct signals to the breathing muscles.^[2][3] CSA is generally less likely to produce snoring than obstructive sleep apnoea. The health consequences of CSA vary considerably depending on the underlying cause, which may include heart failure, stroke or the use of certain medicines, and should be assessed and managed in the context of that underlying condition.^[4][5] Because neither form requires snoring to be present, a significant number of people go undiagnosed for years.

The absence of snoring can also lead partners, family members and even clinicians to overlook the possibility of sleep apnoea. This is particularly relevant for women, who are less likely to present with loud snoring but may still be affected by OSA, often with subtler symptoms. Understanding that sleep apnoea can be silent is an important first step towards seeking appropriate assessment.

What are the signs of sleep apnoea if you don't snore?

Key signs include excessive daytime sleepiness, unrefreshing sleep, morning headaches, nocturia and difficulty concentrating; an Epworth Sleepiness Scale score above 10 supports referral for assessment.

Sleep apnoea without snoring can still produce a recognisable cluster of symptoms that affect both night-time sleep and daytime functioning. The most commonly reported signs include:

• Excessive daytime sleepiness, even after what appears to be a full night's sleep

• Waking with a headache, particularly in the morning, which may be associated with overnight changes in blood oxygen or carbon dioxide levels

• Unrefreshing sleep, where a person feels as tired on waking as when they went to bed

• Frequent night-time waking, sometimes with a sensation of choking or gasping, though this is not always remembered

• Difficulty concentrating or memory problems during the day

• Mood changes, including irritability, low mood or anxiety

• Nocturia (waking repeatedly to urinate at night)

• Dry mouth or sore throat on waking, even without snoring

A bed partner may notice pauses in breathing or restless movement during sleep, which can point towards a sleep-disordered breathing condition. Periodic limb movements may also occur during sleep, though these are not specific to sleep apnoea and can have other causes. People who sleep alone may have no external observer to report these signs.

Many of these symptoms overlap with other conditions, including depression, hypothyroidism and anaemia. This overlap can delay diagnosis, which is why a thorough clinical assessment is important rather than attributing fatigue or poor concentration to lifestyle factors alone. If several of these symptoms are present together, particularly excessive daytime sleepiness combined with unrefreshing sleep, a formal sleep assessment is warranted. As a guide, a score above 10 on the Epworth Sleepiness Scale is generally considered to indicate excessive daytime sleepiness and supports referral for further assessment, in line with UK clinical practice.^[8]

Who is most at risk of silent sleep apnoea?

Women, older adults, people with a higher BMI, type 2 diabetes, cardiovascular conditions or a naturally narrow airway are at greatest risk of sleep apnoea without prominent snoring.

Several groups are at elevated risk of sleep apnoea without prominent snoring, and recognising these risk factors can help prompt earlier investigation.

Women may present with OSA differently from men, with fatigue, insomnia and mood disturbance more prominent than loud snoring. This can mean the condition is misattributed to depression or menopause-related sleep disruption, contributing to underdiagnosis. Overall OSA prevalence is higher in men, but women are less likely to be referred and diagnosed. Pregnancy and polycystic ovary syndrome (PCOS) are also associated with increased OSA risk.^[14][15]

Other groups at increased risk include:

• People with a higher body mass index (BMI), as excess adipose tissue around the neck and upper airway increases the likelihood of airway narrowing

• Older adults, in whom muscle tone in the upper airway naturally decreases with age

• People with type 2 diabetes, who have a higher prevalence of OSA than the general population^[16]

• Those with cardiovascular conditions, including hypertension and atrial fibrillation, which are both associated with sleep-disordered breathing^[22]

• People with hypothyroidism or acromegaly, where hormonal changes can affect airway anatomy

• Individuals with a naturally narrow airway, retrognathia (a recessed jaw) or enlarged tonsils

Central sleep apnoea has a distinct risk profile. It is more common in people with heart failure, those who have had a stroke, and those taking opioid medicines, as well as in people at high altitude.^[4][5] Heart failure is a cardiovascular condition, not a neurological one, though stroke and other neurological conditions also increase CSA risk.

People who sleep predominantly on their back may experience more frequent apnoeic episodes, though positional factors alone do not determine risk. Slim individuals without obvious anatomical risk factors can still develop sleep apnoea, which is why symptom-based assessment matters as much as physical characteristics.

How is sleep apnoea diagnosed in the UK?

Diagnosis involves GP referral to an NHS sleep service, where a home sleep study measures AHI or ODI; in-laboratory polysomnography is used for complex or inconclusive cases.

Sleep apnoea is diagnosed in the UK through a combination of clinical assessment and sleep monitoring, typically coordinated through NHS sleep services following a GP referral. The initial consultation usually involves a structured symptom review, including validated questionnaires such as the Epworth Sleepiness Scale, which measures daytime sleepiness, and the STOP-BANG questionnaire, which screens for OSA risk factors.

For most people, the next step is a home sleep study, also called ambulatory polygraphy or limited channel sleep testing. This involves wearing a small monitoring device overnight that records oxygen saturation, airflow, respiratory effort and heart rate. Results are used to calculate the apnoea-hypopnoea index (AHI), which reflects the average number of breathing pauses per hour of sleep. In UK practice, the oxygen desaturation index (ODI), which measures the frequency of drops in blood oxygen, is also commonly used alongside or instead of AHI to determine severity and guide management. Based on standard clinical definitions used in UK sleep medicine and aligned with NICE guidance (NG202, 2021), an AHI of five to fourteen events per hour is classified as mild OSA, fifteen to twenty-nine as moderate, and thirty or above as severe.

In more complex cases, or where home testing is inconclusive, a full in-laboratory polysomnography may be arranged. This provides a more detailed picture, including brain activity, eye movements and muscle tone, and is particularly useful when central sleep apnoea or other sleep disorders are suspected.

NICE guidance (NG202, published 2021) supports the use of home sleep studies as a first-line diagnostic tool for adults with suspected OSA, helping to reduce waiting times and improve access.^[8][21] Bolt Pharmacy is a GPhC-registered UK online pharmacy offering online consultations, with prescriber review and pharmacist support, for those seeking guidance on sleep-related health concerns alongside other conditions. Diagnosis of sleep apnoea itself, however, requires specialist sleep service involvement.

What treatments are available on the NHS for sleep apnoea?

NICE recommends CPAP as first-line treatment for moderate to severe OSA, mandibular advancement devices for mild cases, and lifestyle changes including weight management and alcohol reduction for all severities.

NHS treatment for sleep apnoea depends on the severity of the condition and any underlying contributing factors, and NICE guidance (NG202, 2021) sets out a stepped approach to management. For mild to moderate OSA, lifestyle modifications are recommended as a first step and can meaningfully reduce the frequency and severity of apnoeic episodes. These include:

• Weight management, as even modest weight loss can reduce airway obstruction

• Reducing alcohol intake, particularly in the evening, as alcohol relaxes upper airway muscles

• Stopping smoking, which is associated with airway inflammation

• Positional therapy, such as avoiding sleeping on the back, for those with positional OSA

For mild symptomatic OSA, mandibular advancement devices (MADs) may be offered as a first-line option. These custom-fitted oral appliances hold the lower jaw slightly forward during sleep, widening the airway.

For moderate to severe OSA, or where lifestyle changes and MADs are insufficient, continuous positive airway pressure (CPAP) therapy is the most effective and widely used treatment. CPAP delivers a steady stream of pressurised air through a mask worn during sleep, keeping the airway open and preventing apnoeic episodes. NICE recommends CPAP as the first-line treatment for adults with moderate or severe OSA.^[8][10] NHS sleep services provide CPAP equipment, fitting, and ongoing support, including help with mask choice and adherence.

Central sleep apnoea may require different approaches, including treatment of the underlying condition driving it, such as heart failure or stroke, or specialist ventilatory support. Adaptive servo-ventilation (ASV) is one device-based option sometimes used in CSA, but it is not recommended for people with symptomatic chronic heart failure with reduced ejection fraction, due to evidence of increased mortality risk in this group (reflected in MHRA device safety guidance and post-SERVE-HF clinical recommendations). ASV should only be considered under specialist supervision with careful patient selection.

Surgical options exist but are generally considered only when other treatments have failed and an anatomical cause has been identified.

When should you see a GP about your sleep and breathing?

See a GP if you regularly experience excessive daytime sleepiness, unrefreshing sleep or morning headaches, or if a bed partner reports breathing pauses, even in the absence of snoring.

You should see a GP about your sleep and breathing if you regularly experience excessive daytime sleepiness, unrefreshing sleep or morning headaches that cannot be explained by other factors, particularly if these symptoms are affecting your ability to work, drive or carry out daily activities. Daytime sleepiness associated with untreated sleep apnoea is a recognised road safety risk. The DVLA requires drivers to notify them and stop driving if they have a condition causing excessive sleepiness until it is adequately treated; the specific requirements depend on the type of licence held and the severity of symptoms, and are set out in the DVLA's guidance on assessing fitness to drive.^[20]

Other reasons to contact your GP include:

• A bed partner reporting that you stop breathing, gasp or choke during sleep

• Waking frequently at night without a clear reason, especially with a dry mouth or sore throat

• New or worsening low mood, anxiety or difficulty concentrating that has not responded to other management

• Nocturia that is disrupting your sleep on most nights

• Any combination of the symptoms described in this article, even in the absence of snoring

You do not need to wait until symptoms become severe. Early diagnosis and treatment of sleep apnoea is associated with better outcomes for cardiovascular health, mental wellbeing and quality of life.^[21][22] Your GP can complete an initial assessment, arrange relevant blood tests to exclude other causes, and refer you to an NHS sleep service where appropriate.

If you experience sudden severe breathlessness, chest pain or a new episode of loss of consciousness, call 999 immediately, as these may indicate a medical emergency unrelated to sleep apnoea. For urgent but non-emergency advice outside GP hours, contact NHS 111. Suspected side effects from any medicine used in the management of related conditions can be reported via the MHRA Yellow Card scheme at yellowcard.mhra.gov.uk.

Scientific References

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2. Central sleep apnoea-a clinical review.
3. Pathophysiology of central sleep apneas.
4. More than Heart Failure: Central Sleep Apnea and Sleep-Related Hypoventilation.
5. Positive Airway Pressure Therapy for Hyperventilatory Central Sleep Apnea: Idiopathic, Heart Failure, Cerebrovascular Disease, and High Altitude.
6. Adaptive servo-ventilation: How does it fit into the treatment of central sleep apnoea syndrome? Expert opinions.
7. Central Sleep Apnea.
8. Obstructive sleep apnoea/hypopnoea syndrome and obesity hypoventilation syndrome in over 16s (NG202).
9. NG202 Terms used in this guideline (AHI severity thresholds).
10. NG202 Chapter 1: Obstructive sleep apnoea/hypopnoea syndrome (CPAP recommendations).
11. Sex inequities in sleep disordered breathing.
12. Age and Sex Matter: Phenotypic Heterogeneity, Diagnostic Gaps, and Screening Tool Performance in Obstructive Sleep Apnea.
13. Gender differences in the psychosocial and functional impact of obstructive sleep apnea: findings from the SHINE patient survey.
14. Clinical characteristics and pregnancy outcomes in polycystic ovary syndrome complicated by obstructive sleep apnea.
15. Obstructive sleep apnea in pregnancy: Nationwide assessment of obstetric characteristics and maternal morbidity at delivery.
16. Global Prevalence and Risk Factors of Obstructive Sleep Apnea in People With Diabetes: A Systematic Review and Meta-Regression.
17. Adaptive servo-ventilation for sleep-disordered breathing in heart failure with reduced ejection fraction.
18. Assessing new treatments for central sleep apnoea in heart failure: sample size considerations for reliable detection of safety signals.
19. Treating sleep disordered breathing for cardiovascular outcomes: observational and randomised trial evidence.
20. Excessive sleepiness and driving.
21. Clinical utility of limited channel sleep studies versus polysomnography for obstructive sleep apnoea.
22. Impact of Obstructive Sleep Apnea Treatment on Cardiovascular Disease Associated Mortality and Morbidity: A Systematic Review.

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