Sleep apnea: symptoms, diagnosis and management

Sleep apnea is estimated to affect nearly one billion people worldwide1, but only 20% of them are diagnosed2. This chronic respiratory condition is characterized by repeated pauses in breathing during the night that impair sleep quality and increase the risk of cardiovascular complications. For more than forty years, Air Liquide Healthcare teams provide support to people living with sleep apnea who are treated with continuous positive airway pressure (CPAP) at home. This page provides an overview of the symptoms, diagnostic tests, available treatments, and the care pathway—from identifying the signs to a personalized daily support plan.

  • Sleep apnea (OSA/OSAHS) is a chronic respiratory disease characterized by breathing pauses lasting more than 10 seconds that occur at least 5 to 10 times per hour during sleep.
  • The main symptoms include snoring, daytime sleepiness, morning headaches, difficulty concentrating, and chronic fatigue.
  • Diagnosis is based on polysomnography or ventilatory polygraphy, and the severity of sleep apnea is assessed by the apnea-hypopnea index (AHI).
  • The standard treatment is continuous positive airway pressure (CPAP) combined with lifestyle and dietary modifications. A mandibular advancement device (MAD) or, in some cases, surgery may be recommended depending on the patient’s medical condition.
  • If untreated, sleep apnea increases the risk of cardiovascular disease, stroke, type 2 diabetes, insomnia, and traffic accidents caused by drowsiness.

What is sleep apnea?

Medical definition of OSA

Obstructive sleep apnea-hypopnea syndrome (OSAHS), more commonly known as sleep apnea, is a severe respiratory disorder that occurs during nighttime rest. Physiologically, this condition is characterized by repeated partial (hypopneas) or total (apneas) closures of the upper airway at the level of the pharynx. An apnea is diagnosed when the interruption in breathing lasts at least 10 seconds and occurs more than 5 to 10 times per hour of sleep. These obstructions cause a temporary drop in blood oxygen levels (desaturation) and force the brain to trigger reflex micro-awakenings to reopen the pharynx and restore breathing. The sleeper is generally unaware of these micro-awakenings, but the quality of their sleep is profoundly impaired.

  • 10 seconds at least interruption in breathing

  • 5 to 10 times per hour of sleep

Obstructive, central, and mixed apnea: three distinct forms

There are three types of sleep apnea, which differ in their physiological mechanisms

  • Obstructive sleep apnea (OSA) is the most common form, accounting for approximately 90% of cases3. It is purely mechanical and results from a relaxation of the pharyngeal muscles and a collapse of the airway.
  • Less common, central sleep apnea originates in the central nervous system. The brain fails to send a contraction signal to the respiratory muscles. This form is not related to a physical obstruction but often results from underlying conditions such as heart failure or the aftereffects of a stroke.
  • Finally, mixed apnea is a combination of the two mechanisms. Typically, an episode begins with a lack of breathing effort (central apnea), followed by a mechanical obstruction when the patient attempts to resume breathing (obstructive apnea).

What are the symptoms of sleep apnea?

Nocturnal symptoms

Signs of sleep apnea are frequently noticed by those around the person living with a sleep apnea during periods of rest. The most common symptom is loud snoring and distressing pauses in breathing, suddenly interrupted by a noisy inhalation. The patient may experience these micro-awakenings, jolting awake with a sensation of choking or suffocation. This very restless sleep is frequently accompanied by night sweats and sudden movements. Finally, nocturia—that is, the need to urinate several times a night—is also a characteristic nocturnal symptom of this respiratory syndrome.

Daytime symptoms and daily impacts

The daytime consequences of OSA stem directly from the lack of restorative sleep and fragmented nights. Upon waking, patients experience a persistent feeling of chronic fatigue and often complain of morning headaches accompanied by a dry mouth. As the day progresses, excessive sleepiness sets in, sometimes leading to involuntary, uncontrollable—and therefore dangerous—falling asleep. These issues significantly impact their daily lives: difficulties with concentration and memory, decreased cognitive performance, as well as irritability and episodes of depression. Intimate relationships can also be disrupted, with many patients reporting a decreased libido and erectile dysfunction.

Specific characteristics in women

Sleep apnea is still frequently underdiagnosed in women4. Its symptoms are more subtle (hypopneas, insomnia, exhaustion, signs of depression) compared to the loud snoring and obvious apneas more typical in men. The prevalence of OSA becomes comparable to that in men after menopause5.

Causes and risk factors for sleep apnea

Anatomical and morphological factors Overweight, obesity, and other factors that can be addressed Non-modifiable factors: age, sex, medical history

Certain anatomical features of the ENT or maxillofacial regions predispose individuals to airway obstruction. Narrow nasal passages, a large tongue, a flat palate, or a receding chin can reduce airflow through the larynx.

Sleeping on one’s back also exacerbates the obstruction due to mechanical collapse of the tongue. In children, enlarged tonsils or adenoids are often the primary anatomical cause of sleep apnea syndrome.

Overweight and obesity are the most significant reversible risk factors. Approximately 70% of diagnosed patients are overweight6.

Evening alcohol consumption, smoking, and sedative medications also exacerbate pharyngeal collapse.

Since the tone of the tracheal muscles decreases with aging, age is a decisive factor. After age 65, 30% of people are affected by sleep apnea7.

Male gender is also a risk factor, with men being twice as likely to be affected as women before menopause8.

A family history of the condition and certain medical histories (such as type 2 diabetes or hypothyroidism) are also associated with an increased risk of developing OSA.

How is sleep apnea diagnosed?

Who should you contact, and when?

If you experience unexplained fatigue, snoring reported by your partner, or abnormal daytime sleepiness, it’s important to see a doctor. An initial appointment with your primary care physician will allow them to assess your symptoms, calculate your Body Mass Index (BMI), and refine the diagnosis using screening questionnaires such as the Epworth Sleepiness Scale. If a diagnosis of sleep apnea is highly likely, the doctor will refer the patient to a sleep center or a healthcare professional specializing in sleep, a pulmonologist, or a cardiologist for further diagnostic testing.

Polysomnography and polygraphy

Confirming a diagnosis of sleep apnea requires measuring nocturnal activity—that is, recording apneas and hypopneas using polysomnography and polygraphy.

  • The ventilatory polygraph test can be performed at home. Sensors record respiratory chest movements, nasal airflow, snoring, and blood oxygen saturation (oximetry).
  • Polysomnography is generally performed at a sleep center or in a hospital. It supplements the polygraphic setup with electrodes (EEG, EMG) that analyze brain and muscle activity, identify each stage of sleep, and detect all micro-awakenings.

Understanding severity: The apnea-hypopnea index (AHI)

Once these tests have been performed, the apnea-hypopnea index (AHI) can be calculated. It corresponds to the number of breathing pauses (apneas) and partial blockages of the upper airway (hypopneas) per hour. This index thus determines the severity of the condition.

  • Mild 5 to 15

    events per hour

  • Moderate 16 to 30

    events par hour

  • Severe > 30

    events per hour

If there are more than 30 apneas and hypopneas per hour, the syndrome is diagnosed as severe and requires treatment.

What are the treatments for sleep apnea?

Continuous Positive Airway Pressure (CPAP), the standard of care

When sleep apnea is severe or moderate with comorbidities, the first-line therapy is continuous positive airway pressure (CPAP). This treatment requires a doctor’s prescription. The CPAP device delivers pressurized ambient air through a flexible tube connected to a mask. This device keeps the airways open by delivering pressurized air. Obstructions are eliminated, oxygen levels return to normal, and the patient regains uninterrupted, restorative sleep. The benefits of treatment depend on good adherence: the CPAP device must be used for at least 4 hours per night9.

To facilitate adherence to CPAP therapy, the healthcare provider will consider several factors at the start of treatment, including the patient’s and their partner’s understanding of the therapy, the comfort of the mask (nasal or full-face), pressure settings, the possibility of implementing remote monitoring, and the ability to review and analyze this data.

Mandibular Advancement Devices (MADs) and other alternatives

For mild to moderate apnea, or in cases of CPAP intolerance, the doctor may prescribe a mandibular advancement device (MAD). This is a type of dental appliance—which can be custom-made—designed to push the lower jaw and tongue forward, thereby helping to open the pharynx during sleep. In exceptional cases where sleep apnea is caused by anatomical factors (such as very enlarged tonsils or a receded upper jaw), ENT surgery may be considered when other approaches have failed.

Lifestyle and dietary measures and weight loss

In addition to medical devices, adopting a healthy lifestyle is encouraged. Weight loss of 10 to 15% can reduce the apnea index and, in some cases, cure mild forms of the condition. It is strongly recommended to reduce tobacco and alcohol consumption, especially in the evening. Establishing a regular sleep schedule, engaging in physical activity, and learning to sleep on one’s side (positional therapy) are also valuable recommendations.

Untreated Sleep Apnea: consequences and risks

Cardiovascular and metabolic risks

Untreated OSA increases cardiovascular risk by a factor of 1.829,10. Chronic oxygen desaturation and repeated respiratory effort strain the heart muscle. This physiological stress contributes to the onset or worsening of chronic high blood pressure. The risks of arrhythmias, coronary artery disease, myocardial infarction, and stroke are increased. Beyond the effects on the heart, chronic lack of rest disrupts cellular metabolism, leading to a high prevalence of metabolic syndrome and type 2 diabetes among people with sleep apnea.

Drowsiness and risk of traffic accidents

Frequent nighttime micro-awakenings lead to sleep debt. A night of disrupted sleep slows reaction time and reduces peripheral vision. The ability to anticipate hazards is also significantly reduced. 30% of fatal traffic accidents are attributable to drowsiness while driving11, and the risk of an accident is up to 7 times higher in untreated OSA patients.

Living with sleep apnea: impact on daily life and loved ones

Sleep apnea and marital life

Untreated sleep apnea poses a major challenge to a couple’s harmony, significantly impacting the partner’s physical and mental health. Nighttime breathing pauses cause constant anxiety in the spouse, who, by monitoring the other’s breathing, increases their own risk of insomnia, fatigue, and daytime sleepiness. This disorder undermines the relationship dynamic, leading to irritability, frustration, tension, and the feeling for the spouse that they are “more of a caregiver than a partner.” Continuous Positive Airway Pressure (CPAP) therapy has been shown to have beneficial effects on the sleep quality of both the patient and their partner.

By reducing snoring (severe snoring) and nocturnal choking episodes, CPAP must be accepted by both the patient and their partner. Studies have shown that the partner’s attitude influences the person with sleep apnea’s adherence to treatment12. The partner’s positive and supportive attitude (encouragement, help with the mask) facilitates the adoption and use of the CPAP device. Open communication about the device and working together to find solutions to potential obstacles (noise, skin irritation) are therefore encouraged to integrate the device into the couple’s daily life and achieve the best health outcomes.

When insomnia and sleep apnea co-occur (COMISA)

COMISA refers to the co-occurrence of chronic insomnia and sleep apnea (OSA). This dual disorder, which affects 30 to 50% of patients with sleep apnea13, is often underdiagnosed, and these conditions exacerbate one another, with serious health consequences. Early diagnosis and a combined treatment approach are key to successful management. In fact, treating chronic insomnia improves adherence to CPAP therapy14. This holistic approach, combining CPAP ventilation with cognitive-behavioral therapy for insomnia (CBT-I) improves patients’ rest, mental health, and quality of life15.

Home support of sleep apnea by Air Liquide Healthcare

The role of the home healthcare provider

Once the medical prescription has been issued, successful adherence to treatment depends in large part on the quality of the support provided by the home health care provider. The respiratory technician or nurse visits the patient at home to explain how the equipment works and how to maintain it, to help the patient choose the most suitable mask, and to answer any questions. They ensure the safety, hygiene, and maintenance of the medical device. The role of the home healthcare provider is to support the patient throughout their therapy, collecting and analyzing adherence data in order to alert the specialist physician to adjust the treatment if necessary or simply to share this information to facilitate treatment monitoring and report on health outcomes.

Personalized support from Air Liquide Healthcare: Sleep Apnea 360

Our goal is for the 2 million people living with sleep apnea whom we support in approximately 30 countries worldwide to follow their therapy at home. Our entities specializing in home healthcare—with VitalAire as our global brand—are rolling out a support program designed to achieve the best health outcomes while simplifying the work of healthcare professionals and minimizing costs to society. The Sleep Apnea 360 program allows us to tailor the initiation of treatment and ongoing support specifically to each patient’s profile, by reactively and proactively adjusting the frequency of interactions, the content of the information shared, and the communication channels used. All these elements are adjusted based on the patient’s profile, adherence, and motivation over time. Thus, our efforts are focused not on the means of action, but on the health outcomes that matter to patients and on our collaboration with healthcare professionals.

Sleep Apnea 360 is built on three pillars:

  • Awareness and education.

    They are an essential first step in helping people recognize symptoms and understand the process of medical screening tests prescribed by their doctor.

  • Personalized initiation, once the diagnosis has been made.

    The goal is to achieve rapid adherence to treatment. During this phase, motivational interviewing helps explore patients’ preconceptions and expectations to address any barriers to therapy and increase their motivation to undergo CPAP treatment. This approach, which facilitates behavioral change through active listening and empathy, aims to significantly increase adherence and improve quality of life.

  • Tailored support to maintain long-term adherence to treatment.

    The program includes remote monitoring of health data. Whether a patient experiences mask leaks, an issue with air pressure settings, or discomfort with their mask, our teams intervene as soon as adherence data drops. Our system analyzes the challenges encountered and triggers an intervention. Furthermore, statistical analysis of adherence data helps our teams identify key trends early on so they can implement the most appropriate personalized support for these high-risk patient profiles. Digital technology and artificial intelligence are therefore powerful tools for providing personalized patient care.

A digital solution —combining a patient app designed to encourage engagement with a platform that facilitates communication with doctors—is made available with the goal of improving patients’ quality of life. Good adherence to CPAP therapy reduces comorbidities16, thereby freeing up time for healthcare professionals and contributing to the sustainability of healthcare systems.

Frequently Asked Questions about sleep apnea

What is the life expectancy for someone with sleep apnea?

When properly treated, sleep apnea has no significant impact on life expectancy. However, if left untreated, it increases the risk of cardiovascular complications (high blood pressure, stroke, heart rhythm disorders) and metabolic complications. This is why early diagnosis and treatment (using continuous positive airway pressure or a mandibular advancement device) are essential.

How can you tell if you have sleep apnea?

Loud snoring, breathing pauses noticed by your partner, extreme fatigue upon waking, daytime sleepiness, morning headaches, and difficulty concentrating are signs to watch for. The Epworth Sleepiness Scale allows for a quick self-assessment. If you have any questions, consult your primary care physician, who will refer you to a pulmonologist or sleep specialist if necessary.

How long does a sleep apnea episode last?

An apnea episode is defined as a pause in breathing lasting at least 10 seconds during sleep. In the most severe cases, these pauses can last up to 30 seconds. They occur about ten times per hour, or even hundreds of times per night, without the person being aware of them.

Can sleep apnea be cured?

Sleep apnea is a chronic condition that does not resolve on its own, but it can be very effectively managed with appropriate treatment. In cases of mild sleep apnea related to being overweight, weight loss can reduce or even eliminate episodes of apnea. For moderate to severe forms, continuous positive airway pressure (CPAP) remains the standard of care.

Who should you see if you suspect you have sleep apnea?

The first step is to see your primary care physician, who will assess your symptoms and refer you to a specialist if necessary: a pulmonologist, sleep medicine specialist, or ENT specialist. The diagnosis is confirmed by a sleep study (polysomnography or ventilatory polygraphy) ordered by the specialist, who will then prescribe an appropriate treatment.

What is the difference between CPAP and PPC?

CPAP (Continuous Positive Airway Pressure) and PPC (pression positive continue) refer to exactly the same treatment. PPC is the French term, while CPAP is the English term used internationally. The principle: a medical device delivers pressurized air into the airways via a mask, which prevents them from collapsing during sleep.

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