Man suffering from sleep apnea and waking up tired

Obstructive Sleep Apnea

Obstructive sleep apnea is a condition characterized by recurring episodes of partial or complete obstruction of the upper airway during sleep. More than 930 million adults worldwide, aged 30 to 69, suffer from obstructive sleep apnea. However, most of them are not aware of this.

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    What Is Sleep Apnea?

    Sleep apnea is a common sleep disorder that impacts millions of people around the world every night.

    Sleep apnea causes you to stop breathing during your sleep. It not only disturbs your sleep but also affects your quality of life and leads to serious health issues.

    There are 3 types of sleep apnea:

    Obstructive Sleep Apnea (OSA)
    This is when your upper airway becomes blocked while you sleep, thereby reducing or completely stopping airflow.
    Central Sleep Apnea (CSA)
    This occurs when your brain does not send the signals needed to breathe.
    Complex or Mixed Sleep Apnea
    A combination of obstructive sleep apnea and central sleep apnea.

    What Is Obstructive Sleep Apnea?

    Obstructive sleep apnea is a condition characterized by recurring episodes of partial or complete obstruction of the upper airway during sleep. It is the most common type of sleep apnea.

    Airway obstructions may be described as hypopneas or apneas:

    Hypopnea is a partial obstruction of the upper airway when airflow is reduced by 30% or more for at least 10 seconds.
    Apnea is a complete obstruction of the upper airway when airflow is reduced by 90% or more for at least 10 seconds.

    The number of episodes of partial (hypopnea) and complete (apnea) airway obstructions can help doctors determine the severity of OSA.

    Severity of Sleep Apnea

    The severity of sleep apnea is usually measured using the apnea-hypopnea index (AHI), i.e. the average number of apneas and hypopneas per hour of sleep.

    There are different levels of sleep apnea severity:

    Mild Sleep Apnea
    AHI of 5 to 14 events per hour.
    Moderate Sleep Apnea
    AHI of 15 to 29 events per hour.
    Severe Sleep Apnea
    AHI of 30 or more events per hour.

    In all cases, sleep apnea can affect a person’s quality of life. Untreated obstructive sleep apnea is associated with an increased risk of mortality and cardiovascular diseases.

    What Happens During Obstructive Sleep Apnea?

    Obstructive sleep apnea usually occurs when the muscles that control the upper airway relax too much while you are sleeping, thereby causing the throat to narrow.

    This is what happens:

    • Your tongue falls backward during sleep, blocking your throat and partially or completely blocking the upper airway.
    • When this happens, the brain sends an alarm to open the airway. This is most often associated with a brief awakening from sleep. During that brief moment, the brain quickly reactivates the muscles that hold the throat open, letting air through to restore oxygen levels. The brain then goes back to sleep. This awakening is usually so brief that you don't remember it.

    This cycle can repeat hundreds of times each night, and cause abnormal levels of both oxygen and carbon dioxide in the blood, as well as fragmented sleep. All of this leads to severe health consequences if left untreated.

    How Common Is Obstructive Sleep Apnea?

    Obstructive sleep apnea is a common sleep disorder.

    A recent analysis suggests that more than 930 million adults aged between 30 and 69 years may suffer from obstructive sleep apnea worldwide *.

    However, even though obstructive sleep apnea is common, many people may not even be aware of their interrupted sleep because they have obstructive sleep apnea. Obstructive sleep apnea is a significant, yet under-diagnosed and under-treated chronic disease.

    How Do I Know if I Suffer From Obstructive Sleep Apnea?

    Some signs of obstructive sleep apnea are:

    • Your bed partner may report loud snoring or times when you gasp, choke, or stop breathing while sleeping.
    • Frequently having headaches when waking up.
    • Waking up most of the time with a dry mouth or the need to urinate.
    • Feeling excessively tired during the day, even after a long night's sleep.

    Think you may have sleep apnea? It’s important to have it checked.

    What Are the Main Risk Factors?

    Anyone can develop obstructive sleep apnea, though certain factors put you at increased risk:

    • Age: Sleep apnea can occur at any age, but the risk increases as you get older. This is because fatty tissue can build up in your neck and tongue as you age, thereby raising the risk of obstructve sleep apnea.
    • Body mass index (BMI): The likelihood of developing obstructve sleep apnea goes up with a person’s BMI, a measure of body fat based on a person’s height and weight. Overweight people can have increased fat deposits in their necks, which can block the upper airway.

    Certain physical features also make a person more likely to develop OSA. These include:

    • A small or set-back lower jaw.
    • Large tonsils and a thick neck. These features may cause obstructive sleep apnea because they narrow the upper airway.
    • Large tongue. A large tongue in the mouth can block the airway while sleeping.
    • Excess fat surrounding the throat.
    • Endocrine disorders, or changes in your hormone levels. Hormone levels can affect the size and shape of your face, tongue, and airway. People who have low levels of thyroid hormones or high levels of insulin or growth hormone have a higher risk of sleep apnea.

    Other risk factors may include:

    • Family background and genetics. Sleep apnea can be inherited, as genes determine the size and shape of your skull, face, and upper airway. Additionally, your genes may increase the risk of other health conditions that may lead to sleep apnea.
    • Unhealthy lifestyle habits. Drinking alcohol and smoking can raise the risk of sleep apnea. Alcohol can make the muscles of the mouth and throat relax, leading to closure of the upper airway. Smoking can also cause inflammation in your upper airway, which affects breathing.
    • Nasal congestion. A stuffy nose may double a person’s chances of experiencing OSA. Nasal congestion can be caused by a variety of factors, including colds, sinus infections, and/or the flu.

    How Is Obstructive Sleep Apnea Diagnosed?

    To diagnose obstructive sleep apnea, doctors look at a patient’s medical history and symptoms, conduct a physical exam, and refer them for a sleep study.

    Medical History

    While reviewing a person’s medical history, a doctor may inquire about risk factors as well as both nighttime and daytime symptoms. In some cases, a doctor may have a person fill out a questionnaire to look for additional symptoms and help differentiate between OSA and other conditions.

    As sleepers may not recognize their night-time symptoms, roommates, bed partners and relatives may be asked to report a person's symptoms.

    Physical Exam

    Doctors typically perform a physical examination to check for physical features that increase the risk of obstructive sleep apnea, including a person’s neck and waist size, and signs of health complications associated with OSA.

    Sleep Study

    A sleep study is necessary to confirm (or repudiate) a diagnosis of obstructive sleep apnea, and also measure the severity of breathing disruptions. Also called polysomnography, a sleep study involves an overnight stay at a specialized sleep laboratory, often located within a sleep center or hospital.

    Sometimes a sleep study can be completed at home with a portable sleep monitor.

    When considered together with a person’s symptoms, the number of breathing events per hour found during a sleep study can help doctors determine the severity of OSA.

    Obstructive Sleep Apnea Treatment

    Positive Airway Pressure (PAP)

    The primary treatment for OSA is positive airway pressure (PAP) therapy.

    PAP therapy involves the use of pressurized air that is pumped through a bedside machine and blown into into the patient's nose and/or mouth to keep the airway open during sleep.

    PAP therapy may be provided using one of the following methods:

    • Continuous positive airway pressure (CPAP).
    • Bilevel positive airway pressure (BiPAP or BPAP).
    • Auto-titrating positive airway pressure (APAP).

    Although CPAP has proven to be a very effective treatment for obstructive sleep apnea, patients are often uncomfortable with the mask and adherence to this type of treatment remains problematic. For this reason, alternative sleep apnea treatments have been developed in recent years *.

    Hypoglossal Nerve Stimulation (HGNS)

    In recent years, new and innovative treatments have emerged for patients who do not tolerate PAP therapy. One of the most promising angles is hypoglossal nerve stimulation.

    Hypoglossal nerve stimulation (HGNS) relies on controlled stimulation of the tongue nerve – the hypoglossal nerve that enables tongue movement – to maintain the airway open during sleep. The effectiveness of HGNS has been scientifically proven.

    This kind of therapy is a serious option for people looking for an alternative to CPAP.

    Hypoglossal nerve stimulation helps to prevent the potential side effects of CPAP therapy such as dry mouth, nasal congestion or skin irritation caused by the mask.

    As it does not involve a CPAP machine and mask, HGNS may be recommended to patients who have failed, are intolerant to, or refuse CPAP therapy.


    Surgery is for people who have anatomical issues causing or worsening their sleep apnea. For example, if you have a deviated nasal septum, swollen tonsils, and adenoids, or a small lower jaw that causes your throat to be too narrow, surgery might help you.

    Surgery remains a last resort option. Sleep apnea doctors usually try other treatments first.

    Oral Devices / Mandibular Advancement Devices (MAD)

    Dental appliances or oral "mandibular advancement" devices keep your tongue from blocking your throat or bring your lower jaw forward. This may help keep your airway open while you sleep.

    MAD therapy is usually more suitable for mild to moderate obstructive sleep apnea.

    Behavior Changes

    Behavior and lifestyle changes can also be a starting point in the treatment of OSA as it allows most people to better manage their condition:

    • Weight loss can be an answer. Even losing 10% of your weight could make a difference.
    • Alcohol and/or sleeping pills should be avoided, as these tend to close the airway during sleep keeping you from breathing like you should for longer periods.
    • Sleeping on your side can help.
    • Nasal sprays can help if sinus problems or nasal congestion make it harder to breathe while you sleep.

    Risks & Complications of Untreated Sleep Apnea

    Untreated obstructive sleep apnea is associated with numerous negative health consequences:

    • Drowsy driving: Driving accidents are a significant risk for people with OSA. Indeed, people with OSA are two to three times more likely to be involved in a car accident than people without OSA.
    • Mental health changes: OSA is associated with a variety of mental health changes, including irritability, depression, and anxiety. People with OSA may also experience impaired attention, memory, and an increased risk of making errors.
    • Cardiovascular disease: OSA increases the risk of health conditions affecting the heart and blood vessels, such as hypertension, an irregular heartbeat, and heart failure. OSA also increases the risk of stroke.
    • Diabetes: People with OSA have a higher likelihood of being resistant to insulin, metabolic syndrome, and type 2 diabetes. OSA can also increase the likelihood of developing complications from diabetes.

    Untreated OSA can be deadly:

    • 2 times more risk of stroke
    • 2.5 times more risk of heart failure
    • 5 times more risk of cardiovascular mortality

    Living With Sleep Apnea

    It’s important for people who are diagnosed with obstructive sleep apnea to be well informed about their diagnosis and understand the importance of appropriate treatment.

    While OSA typically cannot be cured, treatment does help most people reduce breathing disruptions, improve sleep quality, and minimize health consequences.

    The following tips can help people learn to live with sleep apnea:

    • Find support. Daily use of CPAP can be a significant challenge for people diagnosed with OSA. Connecting with other people with OSA through websites and support groups may be a helpful first step in locating accurate information and social support.
    • Be cautious when driving. The side effects of OSA can make it difficult to concentrate and stay alert. People with OSA should be aware of the risks of driving, operating machinery, and performing other dangerous tasks.
    • Follow up regularly with a sleep doctor. After a diagnosis of OSA, people should maintain frequent communication with a sleep specialist to ensure that their treatment is working. Side effects should be monitored over time.
    • Avoid substances that worsen OSA symptoms. For people living with sleep apnea, it’s important to avoid substances that could aggravate breathing issues during sleep. Be sure to talk to a doctor before using sedatives, muscle relaxants, benzodiazepines, narcotics, and alcohol.
    • Talk to your doctor about your health condition. People with sleep apnea need special care when receiving anesthesia or pain medications. As a result, people should discuss their diagnosis with their doctors and medical professionals.

    People living with sleep apnea should also ensure that they get enough sleep each night.

    In addition to comply with their therapy, people can improve their sleep by following basic sleep hygiene practices:

    • Avoid caffeine late in the day, including soda and tea.
    • Don’t drink alcohol at night.
    • Quit smoking altogether, or at a minimum avoid smoking in the evenings.
    • Exercise regularly.
    • Limit any noises in the bedroom.
    • Keep the bedroom as dark and comfortable as possible.

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