Central Sleep Apnea
Obstructive sleep apnea syndrome (or OSAS) describes a condition when there are frequent pauses in breathing during sleep. OSAS is quite a common disorder and affects around 4% of the population.
Cause of sleep apnea:
Sleep apneas are caused when the muscles in your soft palate, uvula (extension of the soft palate which hangs from the roof of the mouth down towards your tongue), tongue and tonsils relax during sleep, narrowing your airways so much that they closes. This stops your breathing for a few seconds, cutting off the oxygen supply to your body and halting the removal of carbon dioxide. Because of this, your brain briefly wakes you up, re-opens your airways and re-starts your breathing. This occurs many times in a night in people with OSAS and makes proper sleep impossible.
Signs and symptoms?
Many people experience apneas during sleep. However, for a positive diagnosis of OSAS, a number of daytime and night-time symptoms should be present. In the daytime, the main symptom is excessive daytime sleepiness (EDS). Other symptoms that you may experience during the day are related to disturbed sleep and EDS, and include tiredness, slight loss of memory, difficulty in concentrating, impaired performance at work or school, headaches and/or feeling sick in the morning, heartburn and feeling depressed. During the night, snoring is common in OSAS patients, because it is also caused by narrowing of your airways. Your partner or friends may have witnessed a pause in your breathing on occasion and told you about it. You may also wake up some times feeling as though you are choking or gasping. Many patients with OSAS have insomnia. This may not show itself as a problem getting to sleep, but may be caused by sleep being regularly disturbed. Other night-time symptoms include wetting the bed, sweating and reduced libido or impotence.
How can sleep apnea be diagnosed? Polysomnography (a method of recording body measurements during sleep) is used to diagnose OSAS. This is usually carried out in a sleep laboratory, and provides full details on factors such as length and quality of sleep, breathing, position of the body and heart rate.
Complication of untreated sleep apnea:High blood pressure
Evidence suggests OSA can lead to high blood pressure (hypertension).
Maintaining a healthy weight, exercising regularly and eating a healthy, balanced diet can all help prevent high blood pressure, as can the appropriate treatment of OSA, such as using breathing apparatus while you sleep.
Road traffic accidents
As someone with poorly controlled OSA can experience excessive daytime sleepiness, they have an increased risk of being involved in a life-threatening accident, such as a car crash. Their risk of having a work-related accident also increases.
Research has shown someone who has been deprived of sleep because of OSA may be up to 12 times more likely to be involved in a car accident.
If you are diagnosed with OSA, it may mean your ability to drive is affected.
Once a diagnosis of OSA has been made, you should not drive until your symptoms are well controlled.
OSA has also been linked to an increased risk of developing type 2 diabetes. This is a lifelong condition that causes a person’s blood sugar (glucose) level to become too high. It may occur in people with OSA if your body becomes less able to break down glucose properly.
However, it is not clear whether people develop diabetes as a direct result of OSA, or whether it is the result of an underlying cause of the condition, such as obesity.
Treating obstructive sleep apnea
Common treatments for obstructive sleep apnea (OSA) include making lifestyle changes and using breathing apparatus while you sleep.
OSA is a long-term condition and many cases will require lifelong treatment.
In most cases of OSA, you will be advised to make healthy lifestyle changes, such as:
- losing weight if you are overweight or obese
- stopping smokingif you smoke
- Limiting your alcohol consumption, particularly before going to bed.
- avoiding sedative medications and sleeping tablets
Losing weight, reducing the amount of alcohol you drink and avoiding sedatives have all been shown to help improve the symptoms of OSA.
Although it’s less clear whether stopping smoking can improve the condition, you’ll probably be advised to stop for general health reasons.
Sleeping on your side, rather than on your back, may also help relieve the symptoms of OSA if you have been diagnosed with the condition.
Continuous positive airway pressure (CPAP)
As well as the lifestyle changes mentioned above, people with moderate to severe OSA will usually need to use a continuous positive airway pressure (CPAP) device.
This is a small pump that delivers a continuous supply of compressed air to you through a mask that either covers your nose or your nose and mouth. The compressed air prevents your throat closing.
CPAP can feel peculiar to start with and you may be tempted to stop using it. But people who persevere usually soon get used to it and their symptoms improve significantly.
CPAP is the most effective therapy for treating severe cases of OSA. As well as reducing symptoms such as snoring and tiredness, it can also reduce the risk of complications of OSA, such as high blood pressure.
Possible side effects of using a CPAP device can include:
- mask discomfort
- nasal congestion, runny nose or irritation
- difficulty breathing through your nose
- headaches and ear pain
- stomach pain and flatulence (wind)
Earlier versions of CPAP also often caused problems such as nasal dryness and a sore throat. However, modern versions tend to include humidifiers (a device that increases moisture), which helps to reduce these side effects.
If CPAP causes you discomfort, inform you’re your DME company (the company providing the breathing apparatus) as the device can be modified to make it more comfortable. For example, you can try using a CPAP machine that starts with a low air pressure and gradually builds up to a higher air pressure as you fall asleep.
Mandibular advancement device (MAD)
A mandibular advancement device (MAD) is a dental appliance, similar to a gum shield, sometimes used to treat mild OSA. They are not generally recommended for more severe OSA, although they may be an option if you are unable to tolerate using a CPAP device.
An MAD is worn over your teeth when you are asleep. It is designed to hold your jaw and tongue forward to increase the space at the back of your throat and reduce the narrowing of your airway that causes snoring.
Off-the-shelf MADs are available from specialist websites, but most experts do not recommend them, as poor-fitting MADs can make symptoms worse. It is recommended you have an MAD made for you by a dentist with training and experience in treating sleep apnea.
An MAD may not be suitable treatment for you if you do not have many (or any) teeth. If you have dental caps, crowns or bridgework, consult your dentist to ensure that they will not be stressed or damaged by an MAD.
Surgery to treat OSA is not routinely recommended because evidence shows it is not as effective as CPAP in controlling the symptoms of the condition. It also carries the risk of more serious complications.
Surgery is usually only considered as a last resort when all other treatment options have failed, and if the condition is severely affecting your quality of life.
A range of surgical treatments have been used to treat OSA. These include:
- tonsillectomy– where the tonsils are removed if they are enlarged and blocking your airway when you sleep
- adenoidectomy– where the adenoids (small lumps of tissue at the back of the throat, above the tonsils) are removed if they are enlarged and are blocking the airway during sleep
- tracheostomy– where a tube is inserted directly into your neck to allow you to breathe freely, even if the airways in your upper throat are blocked
- weight loss (bariatric) surgery– where the size of the stomach is reduced if you are severely obese and this is making your sleep apnea worse
Surgery to remove excess tissue in the throat to widen your airway (uvulopalatopharyngoplasty) used to be a common surgical treatment for OSA, but it is performed less often nowadays.
This is because more effective treatments are available, such as CPAP. This type of surgery can mean you are unable to use a CPAP device properly in the future if you need to.
Soft palate implants
Soft palate implants make the soft palate (part of the roof of the mouth) stiffer and less likely to vibrate and cause an obstruction. The implants are inserted into the soft palate under local anesthetic.
Sleep Medicine of the Brain, Spine & Nerves