Recognising Sleep Apnoea: Understanding Symptoms, Diagnosis and Therapy
Snoring, observed breathing pauses, daytime sleepiness despite a long night. Sleep apnoea is more common than most people think and often goes unrecognised for years, especially in women. How to read the signs, what polygraphy and polysomnography really measure, what CPAP, a device and weight loss may achieve, and when assessment becomes urgent.
Sleep apnoea is one of the most frequently overlooked diagnoses I know. People come in exhausted, irritable, with high blood pressure that will not come down despite three medications, and no one has ever asked them whether they snore at night and whether anyone has observed breathing pauses. Yet the condition is widespread in the population. The HypnoLaus cohort (Heinzer 2015 in Lancet Respiratory Medicine) found moderate to severe sleep-disordered breathing in almost half of the men examined and just under a quarter of the women. An elevated measurement alone is not yet a disease, but tiredness, blood pressure that is hard to control and observed breathing pauses together are a signal that must not be ignored. In this spoke I show how to recognise sleep apnoea cleanly, diagnose it honestly and treat it with a clear head, without panic and without playing it down.
This spoke is the diagnostics and therapy workshop of the sleep cluster for the topic of breathing. We go through the question of what obstructive sleep apnoea actually is, which symptoms point to it and why it looks different in women, how reliable screening questionnaires such as STOP-Bang are, what polygraphy and polysomnography measure, what the apnoea-hypopnoea index means, what risks untreated sleep apnoea carries, and what the three pillars of therapy (CPAP, mandibular advancement device, weight and lifestyle) may achieve. At the end there are three concrete levers for the coming weeks.
What obstructive sleep apnoea really is
In obstructive sleep apnoea, the muscles of the throat relax during sleep to such an extent that the upper airways repeatedly collapse partially (hypopnoea) or completely (apnoea). Breathing falters, the oxygen content in the blood falls, the body reacts with a brief arousal to reopen the airway. This repeats dozens to hundreds of times per night. Those affected usually do not remember these micro-arousals, but they feel the consequence during the day: sleep that is not restorative.
The distinction is important. Obstructive sleep apnoea is by far the most common form. Alongside it there is central sleep apnoea, in which the breathing centre in the brain temporarily fails to send the drive to breathe, often in connection with heart failure or neurological diseases. And there are mixed forms. This distinction is not academic but decides the therapy, and it can only be made through a sleep measurement.
Obstructive sleep apnoea
The airway in the throat collapses mechanically even though the drive to breathe is present. Contributing factors are excess weight, anatomical narrowing, the supine position, alcohol in the evening, sedative medications. The most common form, well treatable.
Central sleep apnoea
The breathing centre temporarily sends no drive to breathe, the airway is open. More common in heart failure, after a stroke, with certain medications. Needs a different assessment and therapy than the obstructive form.
Simple snoring
Noise from vibration in the throat without relevant breathing pauses and without a drop in oxygen. Often harmless for the sleeper, but can be a precursor to or accompany sleep apnoea. The measurement separates one from the other.
Upper Airway Resistance
Increased airway resistance with arousals, but without the formal apnoea criteria. Can cause daytime sleepiness even though the apnoea-hypopnoea index is low. One reason why the number alone is never enough.
How common is sleep apnoea really?
HypnoLaus: sleep-disordered breathing in the general population
Real-World Raphael Heinzer and colleagues examined in 2015 in Lancet Respiratory Medicine 2121 people from the general population of the Lausanne HypnoLaus cohort with full polysomnography at home. Result: an apnoea-hypopnoea index of 15 or more per hour, that is at least moderate sleep-disordered breathing, was found in 23.4 percent of women and 49.7 percent of men. These figures are markedly higher than in older studies. One important reason is more sensitive measurement and scoring criteria. The study also showed associations between a higher index and high blood pressure, diabetes, metabolic syndrome and depression. Heinzer emphasises that a high measurement does not automatically have disease value but must be assessed in the clinical context.
Heinzer R, Vat S, Marques-Vidal P, et al. Lancet Respir Med. 2015;3(4):310-8. doi:10.1016/S2213-2600(15)00043-0 · PMID: 25682233
What follows from this study is a twofold message. First: sleep-disordered breathing is not a rare marginal phenomenon but is widespread in the population, especially with increasing age. A systematic review of 24 studies (Senaratna 2017 in Sleep Medicine Reviews) confirms that the frequency rises with age, male sex and higher body mass index and can be very high in older age (see the sister spoke on sleep in old age). Second: precisely because the pure measurement finding is so common, it must not be confused with a condition requiring treatment. The clinical art lies in recognising in whom the finding explains symptoms and carries follow-on risks, and in whom it does not.
The symptoms: how you recognise sleep apnoea
The typical constellation that makes me pay attention is three things together. First, loud, irregular snoring interrupted by breathing pauses. Second, observed breathing pauses with subsequent gasping for air, usually noticed by the bed partner because those affected notice nothing of it themselves. Third, pronounced daytime sleepiness despite seemingly sufficient sleep duration.
Added to this are further clues that are individually non-specific but together form a pattern: morning headaches, a dry mouth on waking, nocturnal urination, declining concentration and memory performance, irritability and low mood, declining libido and blood pressure that is hard to control.
The classic picture of the loudly snoring, overweight man means that sleep apnoea is often overlooked in women. Women report loud snoring less often and more often report exhaustion, problems falling and staying asleep, morning tiredness, low mood, headaches and inner restlessness. This is easily misinterpreted as stress, menopause or depression. After the menopause the risk rises markedly. Any woman who is permanently exhausted and does not wake up rested should actively raise the topic of breathing during sleep, even without loud snoring.
An important clarification: none of these points proves sleep apnoea, and their absence does not rule it out. There are people with a considerable apnoea-hypopnoea index without classic daytime sleepiness, and there are exhausted people with completely unremarkable breathing. That is exactly why, after the clinical suspicion, a measurement is needed.
Screening: what STOP-Bang and Epworth can really do
Before sending someone to the sleep laboratory, a structured risk assessment serves as a filter. Two tools have become established: the STOP-Bang questionnaire for estimating apnoea risk and the Epworth Sleepiness Scale for capturing daytime sleepiness. Both are screening instruments, not diagnostic tests.
STOP-Bang as a screening tool, 17 studies summarised
Meta-analysis Mahesh Nagappa and colleagues summarised in 2015 in PLoS One a systematic review with meta-analysis on the validation of the STOP-Bang questionnaire, including 17 studies with a total of 9206 people from different populations. STOP-Bang asks about eight items: Snoring, Tiredness, Observed Apnea, Pressure (high blood pressure), BMI over 35, age over 50, neck circumference and male sex. At a threshold of 3 or more points, the pooled sensitivity for moderate to severe sleep apnoea was around 90 percent; with a higher threshold the specificity rises but the sensitivity falls. The core message: a low score makes relevant sleep apnoea unlikely, a high score justifies further assessment but does not replace it.
Nagappa M, Liao P, Wong J, et al. PLoS One. 2015;10(12):e0143697. doi:10.1371/journal.pone.0143697 · PMID: 26658438
STOP-Bang compared with Berlin, STOP and Epworth
Meta-analysis Hsin-Yu Chiu and colleagues compared in 2017 in Sleep Medicine Reviews, in a bivariate meta-analysis of 108 studies, the diagnostic accuracy of four screening tools for detecting obstructive sleep apnoea: the Berlin questionnaire, STOP-Bang, the STOP questionnaire and the Epworth Sleepiness Scale. STOP-Bang showed the highest sensitivity across all severity grades and was thus the best tool not to overlook those affected. The specificity of all questionnaires was moderate, that is: many false-positive hits that then have to be clarified by a sleep measurement. The Epworth Sleepiness Scale measures the subjective tendency to fall asleep in everyday life and complements the picture, but is too weak as a sole apnoea screening tool.
Chiu HY, Chen PY, Chuang LP, et al. Sleep Med Rev. 2017;36:57-70. doi:10.1016/j.smrv.2016.10.004 · PMID: 27919588
In practice this means: a questionnaire is a good filter for deciding who needs a measurement. It is no substitute for one. A high STOP-Bang score in a tired person with high blood pressure is a clear argument for the next stage of diagnostics.
Diagnostics: polygraphy and polysomnography
The diagnosis of sleep apnoea is not made by talking but by measuring. Two procedures are available; they differ in effort and in their informative value.
Polygraphy
Ambulatory cardiorespiratory polygraphy is a measurement that you usually carry out at home in your own bed. A portable device records airflow at the nose and mouth, breathing movements of the chest and abdomen, oxygen saturation in the blood via a finger clip, the pulse, snoring sounds and body position. From these data it is possible to estimate how often breathing falters and how deeply oxygen drops. Polygraphy is well suited to confirming moderate to severe obstructive sleep apnoea when clinical suspicion is high. Its limit: it does not measure sleep directly, so it does not know the true sleep time and the sleep stages, which can distort the calculated index.
Polysomnography
Polysomnography in the sleep laboratory is the comprehensive reference measurement. In addition to the breathing parameters, it records brain waves (EEG), eye movements (EOG) and muscle tone (EMG) and can thereby determine the sleep stages and the actual sleep time. This allows the apnoea-hypopnoea index to be calculated precisely, the sleep structure to be assessed and obstructive sleep apnoea to be distinguished from central sleep apnoea as well as from other sleep disorders. It is indicated for an unclear or contradictory finding, suspected central sleep apnoea, relevant comorbidities such as heart failure, or when polygraphy does not match the clinical picture.
The apnoea-hypopnoea index counts breathing pauses and reductions in airflow per hour: under 5 normal, 5 to under 15 mild, 15 to under 30 moderate, from 30 severe. This number is useful, but it is not the diagnosis. A moderate index in a symptom-free person is assessed differently from a mild index in someone with pronounced daytime sleepiness, blood pressure that is hard to control and pre-existing heart disease. How deeply the oxygen drops and how strongly sleep is fragmented also count. The treatment decision arises from the overall view of the measurement, symptoms and risk profile, not from a single number.
Why untreated sleep apnoea is a risk
The repeated drops in oxygen and arousals strain the body throughout the night. They activate the sympathetic nervous system, drive up blood pressure and heart rate, promote inflammatory processes and disrupt sugar metabolism. Over years this increases the likelihood of high blood pressure, cardiac arrhythmias, heart attack and stroke. The most tangible short-term risk, however, lies during the day: daytime sleepiness increases the risk of accidents in road traffic.
Marin 2005: severe sleep apnoea and cardiovascular events
Real-World José Marín and colleagues followed in 2005 in Lancet, over a mean of around 10 years, a cohort of men: healthy controls, simple snorers, patients with untreated mild to moderate and with untreated severe obstructive sleep apnoea as well as patients treated with CPAP. Men with untreated severe sleep apnoea had markedly more fatal and non-fatal cardiovascular events than all other groups. In the multivariate analysis the risk of fatal events was around threefold higher compared with healthy individuals. In the patients treated with CPAP the event rate was at the level of the healthy individuals. Important: this is an observational study; it shows a strong association but on its own does not prove causality of the treatment.
Marin JM, Carrizo SJ, Vicente E, Agusti AGN. Lancet. 2005;365(9464):1046-53. doi:10.1016/S0140-6736(05)71141-7 · PMID: 15781100
Tregear 2010: CPAP and the risk of accidents in road traffic
Meta-analysis Stephen Tregear and colleagues analysed in 2010 in Sleep nine observational studies on the risk of motor vehicle crashes in drivers with obstructive sleep apnoea before and after CPAP treatment. Result: CPAP markedly reduced the accident risk (risk ratio 0.28, that is around 72 percent lower). Daytime sleepiness improved as early as after a single treatment night, simulated driving performance within 2 to 7 days. This makes the message concrete: anyone who falls asleep at the wheel or experiences microsleep has an acute safety problem that can improve rapidly with therapy.
Tregear S, Reston J, Schoelles K, Phillips B. Sleep. 2010;33(10):1373-80. doi:10.1093/sleep/33.10.1373 · PMID: 21061860
Therapy pillar 1: CPAP
CPAP (continuous positive airway pressure) is the gold standard for moderate to severe obstructive sleep apnoea. A mask over the nose or nose and mouth generates a slight overpressure during sleep that, like a pneumatic splint, keeps the upper airways open. With good adjustment the breathing pauses largely disappear.
SAVE study: CPAP and cardiovascular events
RCT Doug McEvoy and colleagues investigated in 2016 in the New England Journal of Medicine, in the randomised SAVE study, 2717 adults with moderate to severe obstructive sleep apnoea and existing cardiovascular disease. CPAP in addition to usual care could not, compared with usual care alone, significantly reduce the occurrence of major cardiovascular events over the study duration. However, CPAP improved snoring, daytime sleepiness, mood and health-related quality of life and reduced days off work. A major limitation: the mean nightly usage duration was low at around 3.3 hours. This underlines a central truth of sleep apnoea therapy: CPAP can only work as long as and provided it is worn consistently.
McEvoy RD, Antic NA, Heeley E, et al. N Engl J Med. 2016;375(10):919-31. doi:10.1056/NEJMoa1606599 · PMID: 27571048
The honest classification: for quality of life, daytime sleepiness and road safety the data are strongly in favour of CPAP. For the hard cardiovascular endpoint they are more nuanced, which is probably also due to the often low usage duration in studies. The biggest lever for success is not the device itself but getting used to it: a good mask fit, humidified air, patience in the first weeks and medical support. Anyone who wears CPAP for only a few hours gives away the benefit.
Therapy pillar 2: mandibular advancement device
Phillips 2013: CPAP versus mandibular advancement device in direct comparison
RCT Craig Phillips and colleagues compared in 2013 in the American Journal of Respiratory and Critical Care Medicine, in a randomised crossover study with 126 patients with moderate to severe obstructive sleep apnoea, one month of CPAP and one month of a mandibular advancement device each. CPAP reduced the apnoea-hypopnoea index more strongly (to around 4.5 versus 11.1 per hour), but the device was worn longer (on average 6.5 versus 5.2 hours per night). For the clinically important endpoints of daytime sleepiness, driving simulator performance and disease-specific quality of life, both procedures were comparably effective. The explanation: the lower efficacy of the device was offset by better usage.
Phillips CL, Grunstein RR, Darendeliler MA, et al. Am J Respir Crit Care Med. 2013;187(8):879-87. doi:10.1164/rccm.201212-2223OC · PMID: 23413266
The mandibular advancement device holds the lower jaw slightly forward at night and thereby creates more room in the throat. It is above all a serious option for mild to moderate sleep apnoea, as well as for people who do not tolerate CPAP. What is decisive is the individual fabrication with dental and sleep medicine support and a follow-up measurement of whether the device improves the finding. Ready-made devices from the internet are not an equivalent substitute. For severe sleep apnoea, CPAP remains the first choice.
Therapy pillar 3: weight, lifestyle and accompanying factors
Weight loss improves the apnoea index in mild sleep apnoea
RCT Tatu Kemppainen, Henri Tuomilehto and colleagues investigated in 2008 in the American Journal of Rhinology, in a randomised controlled trial, 52 overweight adults with mild obstructive sleep apnoea (apnoea-hypopnoea index 5 to 15). The intervention group received a very low-calorie diet with accompanying lifestyle counselling, the control group received usual counselling. After 3 months the intervention group had reduced the body mass index markedly more (by 5.4 versus 0.5 points) and the apnoea-hypopnoea index fell more strongly in this group (by 3.2 versus 1.3 events per hour). Weight loss can therefore measurably improve the severity of mild sleep apnoea, but in more severe disease it is no substitute for device therapy.
Kemppainen T, Ruoppi P, Seppä J, et al. Am J Rhinol. 2008;22(4):410-5. doi:10.2500/ajr.2008.22.3203 · PMID: 18702908
Excess weight is one of the strongest modifiable factors in obstructive sleep apnoea. Fatty tissue in the neck and throat narrows the airway, visceral fat worsens breathing mechanics. Weight loss can therefore be a real lever, especially in mild to moderate sleep apnoea, even though it does not replace device therapy in severe disease. Alongside this, practical measures help: avoid alcohol in the evening because it relaxes the throat muscles further, critically question sedative sleeping aids, avoid the supine position if the apnoea is position-dependent, and treat an accompanying blocked nose. These measures are not an either-or to device therapy but complement it.
The 4 PNI lenses on sleep apnoea
Nervous system
Every arousal activates the sympathetic nervous system and interrupts deep sleep. Over the night this adds up to chronic sympathetic over-excitation that drives blood pressure and heart rate upwards. Restorative night sleep needs parasympathetic rest phases, which are missing in apnoea.
Immune system
Repeated drops in oxygen (intermittent hypoxia) promote oxidative stress and low-grade systemic inflammation. This is one of the plausible pathways by which untreated sleep apnoea may be linked to cardiovascular risk and metabolic disorders.
Metabolism
Fragmented sleep and hypoxia worsen insulin sensitivity and are associated with metabolic syndrome and type 2 diabetes (Heinzer 2015). Conversely, visceral fat narrows the airway. This can create a cycle that can be interrupted at several points.
Hormonal system
Disturbed sleep shifts the cortisol daily profile, influences leptin and ghrelin and thereby appetite and satiety. In women, the fall in oestrogen and progesterone in the menopause changes airway stability, which partly explains the rising risk after the menopause.
What does not work: typical traps around sleep apnoea
Apps and smartwatches that record snoring or estimate an oxygen saturation can be a useful first prompt to raise the topic. But they are not diagnostics. They replace neither polygraphy nor polysomnography and can both falsely reassure and falsely alarm. A conspicuous clue from the wrist needs medical checking, an inconspicuous one rules nothing out.
Not every snore is sleep apnoea, but snoring with observed breathing pauses, daytime sleepiness or blood pressure that is hard to control is a warning sign that should not be left running for years. Conversely it also holds: quiet or absent snoring does not rule out apnoea, especially in women.
Many break off CPAP therapy in the first weeks because the mask is unfamiliar. The SAVE study (McEvoy 2016) shows how much low usage duration diminishes the benefit. The first weeks are a task of getting used to it, not a test of whether you are made for it. Mask changes, air humidification, pressure adjustment and support solve most problems. Those who persevere here often get their energy back.
The apnoea-hypopnoea index is important, but it is not the whole story. Drops in oxygen, sleep fragmentation, symptom burden and comorbidities belong in the assessment. A mild index in a severely affected person may require treatment, a moderate index in a symptom-free person perhaps not. This weighing belongs in medical hands.
You should get it medically assessed promptly if breathing pauses in sleep observed by others occur together with pronounced daytime sleepiness, blood pressure that is hard to control or high at night, cardiac arrhythmias or a previous stroke or heart attack.
It becomes urgent, that is not deferrable, when falling asleep at the wheel, microsleep in road traffic or during safety-relevant activity occurs, because that is an acute danger to you and others (Tregear 2010 in Sleep). Also to be taken seriously: a nocturnal sensation of choking with sudden waking, new shortness of breath with leg oedema or strong morning headaches with confusion. In these cases, presentation to your primary care physician or to sleep medicine is the right next step. This information does not replace a medical examination.
A recognised sleep apnoea is one of the most rewarding diagnoses of all.
It explains years of exhaustion, it can be measured, and in most cases it can be effectively treated. The first step costs only one honest question: do I snore, does my breathing pause, am I really rested during the day?
Three concrete levers for the coming weeks
Assess the risk in a structured way before you trigger a measurement
Go through the eight STOP-Bang items for yourself: loud snoring, daytime sleepiness, observed breathing pauses, high blood pressure, BMI over 35, age over 50, neck circumference, sex. Ask a bed partner specifically about breathing pauses, because that is the most valuable clue. With a high score or observed pauses, presentation to a physician is the next step (Nagappa 2015, Chiu 2017).
Tackle the modifiable accompanying factors
Independently of later device therapy, some measures provide immediate relief: avoid alcohol in the hours before sleep, medically question sedative sleeping aids, avoid the supine position in position-dependent apnoea, treat a blocked nose, and in case of excess weight initiate a realistic weight loss. Especially in mild sleep apnoea, weight loss can measurably reduce the index (Kemppainen and Tuomilehto 2008).
With therapy: rely on consistent use
When a therapy is recommended, the use decides the success. With CPAP the first weeks are a task of getting used to it: fit the mask, humidify the air, readjust the pressure, stick with it (McEvoy 2016). For mild to moderate apnoea or CPAP intolerance, the individually fabricated mandibular advancement device is a serious alternative with often better wearing time (Phillips 2013). A follow-up measurement shows whether the chosen therapy really takes hold.
What counts in the end
Sleep apnoea is not recognised by a single symptom and not by a single number, but by the overall view: snoring, observed breathing pauses, daytime sleepiness, together with risk factors such as excess weight, age and blood pressure that is hard to control. The suspicion can be structured with a questionnaire, the diagnosis is made by a sleep measurement. And the treatment is effective in most cases when it is applied consistently.
My concern in integrative medicine is to take both sides seriously: the device therapy, which is often indispensable in moderate to severe apnoea, and the accompanying factors such as weight, alcohol, nasal breathing and sleep hygiene, which help determine the severity and support the treatment success. Those who bring both together have the best chances of regaining the night and thereby the day.
Frequently asked questions about recognising sleep apnoea
How do I recognise whether I have sleep apnoea?
The classic triad is three things together: loud, irregular snoring, breathing pauses observed by a bed partner followed by gasping for air, and pronounced daytime sleepiness despite seemingly sufficient sleep duration. Further clues: morning headaches, a dry mouth on waking, nocturnal urination, problems with concentration and memory, irritability, blood pressure that is hard to control. In women, sleep apnoea often shows itself less through loud snoring and more through exhaustion, insomnia, low mood and morning tiredness, which is why it is more often overlooked. Important: none of these points proves sleep apnoea, and their absence does not rule it out. A suspected diagnosis can be structured with a screening questionnaire such as STOP-Bang; the diagnosis is only made by a sleep measurement (polygraphy or polysomnography). This information does not replace a medical examination.
How common is obstructive sleep apnoea?
More common than long assumed. The HypnoLaus cohort study (Heinzer 2015 in Lancet Respiratory Medicine) examined 2121 people from the general population with full polysomnography. An apnoea-hypopnoea index of 15 or more per hour, that is at least moderate sleep-disordered breathing, was found in 23.4 percent of women and 49.7 percent of men. These figures are well above earlier estimates, which is mainly due to more sensitive measurement criteria. The key distinction is between a pure measurement finding and a condition requiring treatment: not every elevated index automatically means disease. It becomes relevant when the measurement finding and symptoms such as daytime sleepiness or comorbidities such as high blood pressure come together. The classification belongs in medical hands.
How reliable is the STOP-Bang questionnaire?
STOP-Bang is a screening tool, not a diagnostic test. It asks about eight items: Snoring, Tiredness (daytime sleepiness), Observed Apnea (observed breathing pauses), Pressure (high blood pressure), BMI over 35, age over 50, neck circumference over 40 centimetres and male sex. Nagappa 2015 in PLoS One summarised in a meta-analysis of 17 studies with 9206 people: at a threshold of 3 or more points, the sensitivity for moderate to severe sleep apnoea is around 90 percent, the specificity is markedly lower. Chiu 2017 in Sleep Medicine Reviews compared STOP-Bang in a bivariate meta-analysis of 108 studies with the Berlin questionnaire, the STOP questionnaire and the Epworth Sleepiness Scale and found STOP-Bang to be the most sensitive tool. Practical meaning: a low STOP-Bang score makes relevant sleep apnoea unlikely, a high score justifies a sleep measurement but proves nothing. The questionnaire does not replace a medical examination.
What is the difference between polygraphy and polysomnography?
Both measure sleep, but in different depth. Polygraphy (also ambulatory cardiorespiratory polygraphy) is a measurement that you usually carry out at home. It records airflow, breathing movements of the chest and abdomen, oxygen saturation, pulse, snoring sounds and body position. It is well suited to confirming moderate to severe obstructive sleep apnoea when clinical suspicion is high. Polysomnography is the more comprehensive measurement in the sleep laboratory. It additionally records brain waves (EEG), eye movements (EOG), muscle tone (EMG) and thereby the sleep stages. This allows the apnoea-hypopnoea index to be calculated more precisely, sleep to be broken down into stages and other sleep disorders to be distinguished. Polysomnography is indicated for an unclear finding, suspected central sleep apnoea, relevant comorbidities or when polygraphy does not match the clinical picture. Which method fits is decided by the treating physician.
What does the apnoea-hypopnoea index (AHI) mean?
The apnoea-hypopnoea index indicates how many breathing pauses (apnoeas) and reductions in airflow (hypopnoeas) occur per hour of sleep. The usual classification: under 5 is considered normal, 5 to under 15 mild, 15 to under 30 moderate, from 30 severe. Important to understand: the AHI is a number, not a complete picture. A moderate index in a completely symptom-free person is weighted differently from a mild index in someone with pronounced daytime sleepiness, blood pressure that is hard to control and cardiovascular pre-existing conditions. Oxygen desaturation, sleep fragmentation and the individual symptom burden also feed into the assessment. That is why the AHI is one building block of the diagnosis, not the diagnosis itself.
What does CPAP really achieve?
CPAP (continuous positive airway pressure) is the gold standard for moderate to severe obstructive sleep apnoea. A mask generates a slight overpressure that keeps the upper airways open during sleep. The effect on daytime sleepiness, quality of life and road safety is well documented: Tregear 2010 in Sleep showed in a meta-analysis of nine studies that CPAP markedly reduced the risk of motor vehicle crashes in those affected (risk ratio 0.28). The cardiovascular benefit is more nuanced. Marin 2005 in Lancet found in an observational study over around 10 years that men with untreated severe sleep apnoea had more fatal and non-fatal cardiovascular events and that CPAP reduced this risk. The randomised SAVE study (McEvoy 2016 in NEJM) with 2717 participants, however, could not show a significant reduction in cardiovascular events for CPAP in addition to standard care, but it improved snoring, daytime sleepiness, mood and quality of life. A major limitation was the on average low usage duration. CPAP can only work as long as and provided it is worn consistently.
Is a mandibular advancement device an alternative to CPAP?
For mild to moderate obstructive sleep apnoea, a mandibular advancement device may be a serious alternative. It holds the lower jaw slightly forward at night and thereby widens the airway in the throat. Phillips 2013 in American Journal of Respiratory and Critical Care Medicine compared CPAP and the device in a randomised crossover study with 126 patients over one month each: CPAP reduced the AHI more strongly, but the device was worn longer (on average 6.5 versus 5.2 hours per night). For important health endpoints such as daytime sleepiness, driving simulator performance and quality of life, both procedures were comparably effective, because the lower efficacy of the device was offset by better usage. The device belongs in the hands of dentistry and sleep medicine together, not from the internet. For severe sleep apnoea, CPAP remains the first choice.
When should I get sleep apnoea checked urgently?
You should get it medically assessed promptly if several of the following points apply: breathing pauses in sleep observed by others, pronounced daytime sleepiness with a tendency to fall asleep in monotonous situations, blood pressure that is hard to control or high at night, cardiac arrhythmias, a previous stroke or heart attack, heart failure or type 2 diabetes. It becomes urgent, that is not deferrable, when falling asleep at the wheel or microsleep occurs in road traffic or during safety-relevant activity, because that is an acute danger to you and others (Tregear 2010 in Sleep). Also to be taken seriously: a nocturnal sensation of choking with sudden waking, new or increasing leg oedema together with shortness of breath, or pronounced morning headaches with confusion. In these cases, presentation to your primary care physician or to sleep medicine is the right next step. This information does not replace a medical examination.
More from the cluster "Treating Sleep Disorders Holistically"
- Pillar: Treating Sleep Disorders Holistically
- Spoke 17: Sleep in Old Age
- Spoke 10: Recognising Sleep Apnoea (you are here)
Connections to other topics
The pillar article of the sleep cluster. Sleep apnoea is one of the most important physical causes of non-restorative sleep and belongs in every thorough sleep assessment.
With increasing age the frequency of sleep-disordered breathing rises markedly (Heinzer 2015). How sleep, breathing and recovery change in old age and what to watch out for then.
Sources and further reading
- Heinzer R, Vat S, Marques-Vidal P, et al. Prevalence of sleep-disordered breathing in the general population: the HypnoLaus study. Lancet Respir Med. 2015;3(4):310-8. doi:10.1016/S2213-2600(15)00043-0 · PMID: 25682233 [Real-World]
- Nagappa M, Liao P, Wong J, et al. Validation of the STOP-Bang Questionnaire as a Screening Tool for Obstructive Sleep Apnea among Different Populations: A Systematic Review and Meta-Analysis. PLoS One. 2015;10(12):e0143697. doi:10.1371/journal.pone.0143697 · PMID: 26658438 [Meta-analysis]
- Chiu HY, Chen PY, Chuang LP, et al. Diagnostic accuracy of the Berlin questionnaire, STOP-BANG, STOP, and Epworth sleepiness scale in detecting obstructive sleep apnea: A bivariate meta-analysis. Sleep Med Rev. 2017;36:57-70. doi:10.1016/j.smrv.2016.10.004 · PMID: 27919588 [Meta-analysis]
- Tan A, Hong Y, Tan LWL, et al. Validation of the STOP-Bang questionnaire as a preoperative screening tool for obstructive sleep apnea: a systematic review and meta-analysis. BMC Anesthesiol. 2022;22(1):366. doi:10.1186/s12871-022-01912-1 · PMID: 36451106 [Meta-analysis]
- Marin JM, Carrizo SJ, Vicente E, Agusti AGN. Long-term cardiovascular outcomes in men with obstructive sleep apnoea-hypopnoea with or without treatment with continuous positive airway pressure: an observational study. Lancet. 2005;365(9464):1046-53. doi:10.1016/S0140-6736(05)71141-7 · PMID: 15781100 [Real-World]
- McEvoy RD, Antic NA, Heeley E, et al. CPAP for Prevention of Cardiovascular Events in Obstructive Sleep Apnea. N Engl J Med. 2016;375(10):919-31. doi:10.1056/NEJMoa1606599 · PMID: 27571048 [RCT]
- Phillips CL, Grunstein RR, Darendeliler MA, et al. Health outcomes of continuous positive airway pressure versus oral appliance treatment for obstructive sleep apnea: a randomized controlled trial. Am J Respir Crit Care Med. 2013;187(8):879-87. doi:10.1164/rccm.201212-2223OC · PMID: 23413266 [RCT]
- Tregear S, Reston J, Schoelles K, Phillips B. Continuous positive airway pressure reduces risk of motor vehicle crash among drivers with obstructive sleep apnea: systematic review and meta-analysis. Sleep. 2010;33(10):1373-80. doi:10.1093/sleep/33.10.1373 · PMID: 21061860 [Meta-analysis]
- Kemppainen T, Ruoppi P, Seppä J, et al. Effect of weight reduction on rhinometric measurements in overweight patients with obstructive sleep apnea. Am J Rhinol. 2008;22(4):410-5. doi:10.2500/ajr.2008.22.3203 · PMID: 18702908 [RCT]
- Senaratna CV, Perret JL, Lodge CJ, et al. Prevalence of obstructive sleep apnea in the general population: A systematic review. Sleep Med Rev. 2017;34:70-81. doi:10.1016/j.smrv.2016.07.002 · PMID: 27568340 [Systematic Review]