What is Sleep Apnea Syndrome?
Sleep apnea syndrome (SAS) is a condition that is characterized by frequent periods of stopping breathing (apnea) and shallow or slow breathing (hypopnea). This condition is often associated with symptoms like being extremely tired during the day and serious heart-related conditions. It’s important to understand that ‘sleep apnea’ is a broad term covering a range of sleep-related breathing problems from central to mixed, obstructive sleep apnea, and hypopnea.
Obstructive sleep apnea, a form of SAS, happens when there’s a blockage or collapse in the upper part of the airway during sleep. This leads to symptoms like snoring, pauses in breathing, abnormally slow or shallow breathing, or being suddenly woken up due to difficulty breathing.
The causes, occurrence rate, physical signs, methods for diagnosis, and complications of sleep apnea syndrome are discussed in greater detail in this article. More specific information about central and obstructive sleep apnea, two main types of sleep apnea syndrome, are also discussed separately.
What Causes Sleep Apnea Syndrome?
What contributes to a collapse in the upper airway (the part of the body that allows air to flow from the mouth or nose to the lungs) are things that affect how open it remains. The upper airway is surrounded by the bones of the face and head. This serves as a framework for the upper airway and plays a key role in determining whether it stays open or collapses. So, if someone has features like a receding jaw or a deficiency in the upper and lower jaw bones, the soft tissues of the upper airway end up in a tighter space, reducing how open the upper airway remains.
On the other hand, the size and ability to squeeze the soft tissues within the framework of the facial and head bones also determines if the upper airway remains open. It’s less open when there’s more tissue in a given confined space within these bones. This can be influenced by factors such as the amount of fat beneath the mouth lining or on the tongue, as well as the amount of pressure in the neck’s blood and lymph vessels, and the influence of nerves and muscles on the muscles of the upper airway.
Risk factors considered most important for developing Obstructive Sleep Apnea (OSA), a disorder where breathing stops and starts during sleep due to airway blockage, include aging, obesity, being male, and having abnormalities in the facial and head bones. Other risks include smoking and having family members who also have OSA.
Risk Factors and Frequency for Sleep Apnea Syndrome
Sleep-related breathing disorders, particularly obstructive sleep apnea (OSA), are relatively common in the general population, including people with heart conditions. The percentage of people suffering from these conditions varies significantly. OSA is most often seen in males, but women and children can also have the condition. Notably, after menopause, the rates of OSA in women come close to those of men.
- The prevalence of Sleep Apnea Syndrome (SAS) is between 21% to 59%.
- In North America, approximately 15 to 30 percent of males and 10 to 15 percent of females have OSA.
- OSA is more common in African Americans compared to other racial groups in the United States, regardless of body weight.
- The trend of rising OSA rates is linked to increasing obesity levels as well as better diagnosis and detection methods.
- A study estimates that the prevalence of OSA in adult American males rose from 11 to 14 percent between 1990 and 2010.
Signs and Symptoms of Sleep Apnea Syndrome
If someone is showing signs or symptoms of Obstructive Sleep Apnea (OSA), it is essential to carefully review their complete history. This would involve asking questions about possible symptoms such as feeling sleepy during the day, disrupted sleep, snoring, choking or coughing while sleeping, waking up with a headache, chest pain, difficulty breathing, or experiencing changes that affect mental well-being. It’s equally important to investigate their sleep habits and check for other sleep-related issues. Ensuring the reported tiredness is tied to OSA as opposed to simple fatigue helps to clarify the diagnosis.
A comprehensive physical check and taking a detailed a history from the patient are key in figuring out if they have OSA. The doctor would particularly focus on any parts of the upper airway where there could be a blockage. They must thoroughly investigate the nasal cavity for possible issues like offset nasal septum, swelling of the bone and soft tissue in the nose, presence of lumps or unusual growths, a collapsing nasal valve, or growth of adenoids. The throat is equally carefully checked for factors that could be causing blockage such as an enlarged soft palate or uvula, which are often seen in patients with chronic obstructive lung diseases. The doctor also looks out for swollen palatine tonsils, a larger than normal tongue and how these affect throat patency. Frequently used tools like the Updated Friedmann Staging System for Obstructive Sleep Apnea are used for evaluating throat blockages by categorizing based on tongue position, size of the palatine tonsil and the body mass index.
The throat and larynx are examined for things like the shape and collapse of the walls of the throat, size and shape of the epiglottis, swelling of lingual tonsils and potential obstructive lumps or growths. However, examining these structures in a awake patient is a matter of debate. Some doctors prefer to do this while the patient is conscious using a mirror or a flexible fiberoptic laryngoscope which provides a detailed view of the structures. There are also scoring systems available like the Modified Cormack-Lehane scoring system which helps in communicating findings about the anatomy of the larynx in relation to OSA. This approach, though, has its limits as it doesn’t mimic the dynamic changes that happen while sleeping. Consequently, techniques have been developed to mimic these changes in a conscious patient, but they too have proved to be of limited use.
A new method, Drug-Induced Sleep Endoscopy (DISE), provides an alternative way to examine the upper airway. In this method, the patient is made to lie on their back and sedated, after which a flexible fiberoptic laryngoscope is inserted to observe. This gives a more realistic visual of the state of affairs since it simulates the conditions of sleep. Even so, this technique sparks controversy due to inconsistent standards of application and questions on its place in the diagnosis and treatment of OSA.
The doctor would also evaluate the skull and facial skeleton, looking at things like the shape of the jawbone, narrowness of the jaw or upper dental arches, signs of deficient upper and lower jaws, and possible bony growths that could cause blockage. Additionally, the anatomy of the neck is investigated. Having a neck circumference greater than 17 inches for males and greater than 15.5 inches for females can indicate a higher risk of OSA. Other general body characteristics like obesity, fat distribution, dwarfism, or chest wall deformities are looked for. It’s also important to check for possible side effects related to the heart, such as high blood pressure and peripheral edema (swelling caused by fluid buildup).
Testing for Sleep Apnea Syndrome
If you often feel sleepy during the day and show two or more of the following symptoms: high blood pressure, loud snoring, or have been noticed to stop breathing or make choking sounds while sleeping, your doctor may recommend tests for obstructive sleep apnea (OSA). OSA is a condition that causes you to stop breathing for short periods while sleeping. Even if these symptoms are not present, if there is a concern about OSA due to your overall health or if OSA needs to be ruled out for another health issue, similar tests may be recommended.
A tool your doctor might use to gauge your level of sleepiness is called the Epworth Sleepiness Scale. This scale asks you questions about the likelihood of falling asleep in certain situations, with a scoring system of 0-3, where ‘0’ represents never falling asleep and ‘3’ indicates a high chance of dozing off. If your total score is more than 10, it could suggest you might have OSA.
The best way to diagnose OSA is by doing an overnight sleep study, known as a polysomnogram, at a sleep clinic. Sometimes, it might be possible for the polysomnogram to be done in your home, especially if no other sleep-related conditions are suspected, an appropriate sleep study device is available for home use, and a sleep expert can interpret the results. However, if the home polysomnogram is unclear or if OSA is still suspected despite normal findings from the home polysomnogram, a lab-based polysomnogram will be recommended.
A polysomnogram tracks different kinds of sleep data, which are represented as ‘indexes’. The Apnea Index counts how often you stop breathing during each hour of sleep. The Hypopnea Index counts how often your breathing becomes unusually shallow. The Apnea-Hypopnea Index combines these two numbers. The RERA Index refers to how often you have minor episodes of restricted breathing. Other indexes may include the Central Apnea Index, counting the total number of central apneas (where your brain stops sending signals to the muscles that control your breathing) and the Mixed Apnea Index that represents a combination of central and obstructive apneas. These indexes help guide your doctor in diagnosing OSA.
An OSA diagnosis is confirmed if a polysomnogram demonstrates five or more episodes of obstructed breathing per hour (referred to as an Apnea-Hypopnea Index or Respiratory Disturbance Index of 5 or more) along with any sleep-associated symptoms or conditions. Alternatively, OSA could also be diagnosed when 15 or more obstructive respiratory events per hour are recorded regardless of the presence of associated symptoms or conditions. Based on the severity, OSA is categorized into mild, moderate, and severe: mild OSA is indicated if these rates fall between 5 and 14, moderate between 15 and 30, and severe if they are over 30.
Treatment Options for Sleep Apnea Syndrome
If you’ve been diagnosed with Obstructive Sleep Apnea (OSA), a condition where you stop and start breathing during sleep, it’s essential to understand the risks and what you can do to manage your condition. It’s essential to know that untreated OSA can lead to other health issues and even increase your risk of being involved in a car accident. If you’re planning to undergo anesthesia or start on sedating medications, you’ll need to discuss this with your doctor first.
You can take several steps towards improving your health. For those who are overweight, regular exercise and a healthy diet can make a significant difference, as losing weight can ease symptoms like daytime sleepiness and help manage your blood pressure. It’s also crucial to develop good sleep habits and possibly even change your sleep position. You should be aware that drinking alcohol and taking sedating medications might make your OSA worse.
The most common treatment for almost all OSA patients is positive airway pressure therapy. This involves wearing a mask while you sleep that keeps your airways open by pumping in air at a continuous rate. This therapy can greatly reduce sleepiness, lessen the risk of car accidents, help control blood pressure, and enhance your overall life quality. The critical part of this treatment is sticking with it, as many patients either don’t use their devices or don’t use them enough.
If the positive airway pressure therapy isn’t right for you, there are alternative treatments such as custom oral appliances. These devices can reduce problems like snoring, sleep disturbances, and low blood oxygen levels. Nonetheless, oral appliances can cause issues like tooth and jaw pain, dry mouth, and gum irritation. And they usually work best for younger, less overweight patients with mild to moderate OSA.
Surgical intervention, such as trimming the tonsils or straightening the nasal septum, can be considered if other treatments aren’t effective. Such procedures aim to remove potential sites of obstruction in your breathing pathways and may involve a hospital stay and recovery period. Some patients who can’t use positive pressure therapy or don’t benefit from it enough may be candidates for a nerve stimulation device that maintains open airways by moving the tongue forward, depending on their body mass index. It’s important to note, though, that while a tracheostomy (a surgical procedure that creates an air passage at the front of the throat) is a treatment option, it’s not commonly chosen unless the OSA is severe, or there’s another condition that also requires this procedure.
What else can Sleep Apnea Syndrome be?
It is crucial to explore other possible diagnoses in addition to obstructive sleep apnea (OSA), as patients may have other conditions related to sleep happening at the same time. This is not just important for accurately diagnosing OSA, but also helping with overall sleep health.
Obstructive sleep apnea must be distinguished from central sleep apnea, as well as from problems like primary snoring or laryngospasm. There are also other potential reasons for feeling overly tired during the day, such as:
- Narcolepsy
- Periodic limb movement disorder
- Restless leg syndrome
- Circadian rhythm disorders
- Issues related to sleep hygiene
If the doctor suspects one of these conditions, they might recommend further testing. For instance, a patient suspected of having narcolepsy might undergo a test called a multiple sleep latency test.
What to expect with Sleep Apnea Syndrome
If you are suffering from Obstructive Sleep Apnea (OSA), a condition where your breathing repeatedly stops and starts during sleep, your short-term outlook is usually good. Treatments for mild OSA often result in improvement of symptoms. However, these treatments don’t seem to impact long-term heart-related outcomes.
It’s vital to know that if OSA is not treated, it can be dangerous, potentially even life-threatening. Excessive sleepiness during the daytime, a result of OSA, can lead to a higher risk of dying from motor vehicle crashes and other sleepiness-related accidents. People with moderate to severe OSA are at an increased risk of developing heart and lung diseases, stroke, and mental health conditions, if not treated. Despite these risks, it’s important to know that currently available treatments have not been proven to reduce the long-term risk of death, heart events or cognitive function issues.
Possible Complications When Diagnosed with Sleep Apnea Syndrome
People who have obstructive sleep apnea, or OSA, have a higher chance of experiencing several negative health outcomes. A prime example is that they are likely to be involved in car crashes more frequently – two to three times as often as people who don’t have this condition. This fact is especially significant for people like commercial drivers who spend a lot of time on the road. It’s crucial to provide these individuals with effective treatment for their OSA.
Furthermore, obstructive sleep apnea can lead to problems related to brain function, such as difficulty concentrating, memory issues, cognitive deficits, and problems with executing tasks. Additionally, people with OSA are more likely to suffer from mood disorders, psychosis, and sexual dysfunction compared to the general population.
Lastly, OSA can have serious impacts on heart and lung health. These patients have a higher risk for heart diseases, high blood pressure, heart irregularities, heart failure, high blood pressure in the lungs, stroke, and type II diabetes complications. They are also twice or thrice as likely to have non-alcoholic fatty liver disease, even when weight is not a factor.
Common Risks for OSA patients:
- Increased risk of car accidents
- Difficulties with concentration, memory, and task execution
- Higher likelihood of mood disorders, psychosis, and sexual dysfunction
- Increased risk of heart diseases, high blood pressure, heart and lung-related complications
- Increased risk of complications related to type II diabetes
- Two to three times increased likelihood of having non-alcoholic fatty liver disease
Preventing Sleep Apnea Syndrome
Obstructive Sleep Apnea (OSA), a common sleep disorder that can lead to various health problems, is often screened for by doctors. If you’re diagnosed with this condition, your doctor will likely explain what OSA is, what you can expect going forward, and the different ways it can be treated. Treatment options can range from changes in your lifestyle to positive pressure therapy (a treatment that uses a machine to help you breathe), and other methods, based on what’s best for you. They’ll also discuss with you the importance of regular check-ups to keep an eye on your condition and prevent possible complications.
