Snoring and Obstructive Sleep Apnoea

What is Snoring?

Snoring is the sound caused by the vibration of the walls of the air passages and throat when it partially collapses during sleep. The prevalence has been reported to range from 5% to more than 80% in various population studies. In people who snore, the upper airway is narrow. When awake, the airway muscles keep the air passages open but during sleep, the muscles surrounding the air passages relax causing collapse. Intermittent collapse while breathing produces vibration and this is snoring. Snoring can be disturbing and cause sleep disturbance to sleeping partners; it can also lead to increased risk of divorce in married couples. Some people who snore are also embarrassed by it. Snoring if associated with choking, unrefreshing sleep, daytime sleepiness or fatigue may suggest the presence of a medical condition called Obstructive Sleep Apnoea (OSA).

What is Obstructive Sleep Apnoea (OSA)?

Apnoea is Greek for cessation of breathing. OSA is a condition where there is repeated upper airway closure during sleep. This choking, caused by the body's own tissue, causes Oxygen levels to drop. This is sensed by the brain which needs to wake itself up temporarily to open the airway to breathe before falling back to sleep again. On returning to sleep the obstruction occurs again and this cycle repeats. This causes poor sleep quality and unrefreshing sleep. The awakenings from sleep (called arousals) are often not remembered and someone with OSA is usually unaware of how many times choking occurs. In severe cases this can occur more than 30 times an hour during sleep.

What are the causes of Snoring and OSA?

There are many causes of a narrow airway and OSA, most patients have multiple causes. Some factors such as abnormal shape of the facial bones may be inherited but others may develop over time and this may include nasal problems that narrow the nose passages, tonsils and adenoid enlargement or obesity. Increasing age also predisposes to snoring due to laxity of the tissues in the air passages causing increased collapsibility. Alcohol causes the airway muscles to be weaker and consumption of alcohol can worsen snoring. Being overly tired does not cause snoring or OSA but it is the catching up on sleep after sleep deprivation that may make snoring or OSA worse. This is because when the body tries to catch up with lost sleep, there is a greater percentage of deep sleep and rapid eye movement (REM) sleep during the sleep period. Snoring and OSA tend to be worse during these types of sleep.

What are the symptoms of OSA?

There are many symptoms associated with OSA and not all patients have all the symptoms. In fact some patients with severe OSA may even have very few symptoms. Most of these symptoms are also not exclusive to OSA, there can be overlap of these symptoms with other conditions.

Daytime symptoms include:

- Unrefreshing sleep

- Daytime sleepiness

- Waking up with a dry mouth or throat

- Headaches on waking

- Mood problems like Depression, Anxiety

- Poor memory and concentration

Night time symptoms include:

- Loud snoring which may disturb sleeping partners

- Frequent awakenings from sleep

- Frequent trips to the toilet to pass urine

- Poor ability to stay sleep through the night (Sleep maintenance insomnia)

Using symptoms alone to diagnose OSA is inaccurate but it does raise the suspicion of the condition. It is therefore important to do an overnight sleep study to confirm OSA.

How is Primary Snoring and OSA diagnosed or confirmed?

A diagnosis of OSA is made by doing an overnight sleep study. There are several different types of sleep studies available and the most accurate types will include wires on the head to monitor the brain waves, eye movements and muscle activity during sleep. During this study, other wires on the body record the breathing pattern, heart rhythm, Oxygen level, sound level and body movement. Once OSA is confirmed, the sleep study will help guide the treatment approach. If the sleep study is negative for OSA in a snorer, the diagnosis is Primary Snoring i.e. snoring in the absence of airway obstruction.

What are the consequences of untreated OSA?

There are 3 main groups of consequences:

1. Increased risk of developing other serious medical conditions. Untreated OSA increases the risk of developing high blood pressure, heart disease and Strokes and Diabetes. These medical problems have serious medical consequences that will decrease the quality of life and one's lifespan.

2. Effects of poor sleep quality. Poor sleep quality causes excessive sleepiness may predispose to accidents in the workplace if one is operating heavy machinery or on the road if one is driving. Mood disturbances and poor memory may affect the quality of life.

3. Social problems due to snoring. Snoring by itself is not dangerous, however it may create social problems and cause sleep disturbance to the sleeping partner. This can strain relationships and increase risk of divorce. Some female snorers are also embarrassed by their snoring.

Do children snore too? Can children have OSA?

Children can develop OSA as well. The most common causes are enlarged tonsils and adenoids and uncontrolled nasal allergy. Symptoms in children may be different from adults. Children with OSA may be hyperactive in the daytime and have poor concentration in school. They may sweat during sleep, mouth breathe or have restless sleep. Disruption of sleep interrupts the secretion of Growth Hormone which is secreted during Deep Sleep. This may affect the development of a child's physical and mental growth. If this is not detected, children with OSA do not achieve their full growth potential and this may cause consequences later in adulthood.

How is Snoring and OSA treated?

There are multiple treatment options for OSA and snoring and the treatment approach is similar. Unfortunately there is no medication to cure this problem and no ideal treatment for all patients as all options have varying success rates and different potential side effects. In other words, there is no one size fits all solution. There are many types of treatments available and these consist of lifestyle changes and specific therapies. The most suitable treatment method (or methods, as some may need to be combined) has to be decided with your doctor taking into account your preferences, severity of your symptoms or sleep apnoea and effectiveness/side effects of the treatment method. It is important to understand all treatment options available before an informed decision can be made. Usually non-invasive treatment methods are tried first.

Are there any lifestyle changes that can be done?

Behavioural and lifestyle measures like losing weight if one is obese or stopping smoking are part of the management of OSA and snoring. Other measures include avoidance of alcohol as this depresses the airway muscle function. Regular sleeping schedules and avoiding sleep deprivation can also be helpful.

Different sleeping positions may affect snoring. Sleeping on the back may make snoring and OSA worse, therefore sleeping while lying on the side may improve this. However this may not true for everyone. A sleep study should be able to tell if a change in sleeping position will make any difference to the snoring and OSA.

What are the specific therapies for snoring and OSA?

On top of lifestyle changes and behavioural measures, the specific treatment options include Continuous Positive Airway Pressure therapy (CPAP), dental splints or surgery. These 3 treatment options work by various means to prevent the collapse of a narrow airway.

CPAP is positive pressure delivered by a machine that blows out air (like a reversed vacuum cleaner) and is connected to a hose and mask that is worn during sleep. The air pressure can be regulated and some CPAP machines have an automatic titrating function that will adjust the pressure according to need. Positive air pressure works by stenting the airway open thus preventing collapse, snoring and stoppage of breathing. There may be mild side effects from CPAP use like dry mouth or throat, blocked nose or ears and minor skin ulcers. Some patients may find CPAP use difficult to tolerate but those who are compliant with CPAP can have their OSA and snoring well controlled.

Dental splints are devices that protrude the lower jaw by keeping the lower teeth in a more forward position. This splint is also worn during sleep. By maintaining the lower jaw in a protruded position it enlarges the air space behind the tongue and puts the air passage tissues in greater tension. This decreases the tendency for the airway walls to collapse. Side effects from dental splints can include excessive salivation during sleep, jaw opening problems and malocclusion. Success rates for the use of dental splints may vary and may be less successful for those who are obese, elderly and have severe OSA.

Can surgery be done for Snoring and OSA?

There are many types of surgery for the treatment of snoring and OSA.

What is important to understand about surgery is not the different surgical techniques involved but when and why you should consider surgery. This is because surgery may not be suitable for everyone and may involve risks and result in potential side effects. The reasons you consider surgery are as follows:

1. When there is a simple obstruction in the airway that can be solved with simple surgery to give a high rate of cure, surgery should be done early. An example of this would be children with OSA. Children with OSA usually only have large tonsils or adenoids blocking the air passage. Removal of the tonsils and adenoids is a fairly simple procedure and this will give a high chance of cure. Therefore surgery is one of the first line treatments for children with OSA. Unfortunately most adults with OSA do not have this pattern of obstruction.

2. When there is upstream obstruction in the airway that interferes with non-invasive treatment. An example of this is severe nasal obstruction that prevents CPAP or dental splint use. Surgery to the nose can help to open up the obstructed part to enable better treatment. As there are other parts of the air passage lower down which have not been widened with nose surgery, the OSA will unlikely be cured.

3. After a trial of non-invasive treatment, when there is failure or rejection of the treatment options. In other words, surgery to cure OSA in this case is a last resort.

As there may be several points of narrowing in the air passage; the common sites of narrowing include the nose, tonsils, soft palate, back of tongue and sides of the throat. Surgery works by removing or repositioning tissues in or around the airway to enlarge it. As there are multiple areas of narrowing, multiple surgical procedures may be needed.

These procedures may be performed on the tonsils, soft palate, nose, tongue or jaws. In addition to surgery done under general anaesthesia, there are also minimally invasive surgical procedures like Pillar Implants and radiofrequency treatment that can be performed under local anaesthesia but these procedures are more effective for simple snoring and mild OSA. Success rates for surgery vary depending on the surgery, severity and site of obstruction. There is no data on how long successful surgical treatment lasts. Relapse of symptoms over time after successful treatment is variable and is usually due to worsening of the OSA. This may be due to weight gain or increasing age.

Are there any other treatment methods for OSA?

There are several home remedies and off the counter treatments which are not proven to help with OSA. It is potentially dangerous to use some off the counter treatments to treat snoring before OSA is excluded as these do not treat OSA effectively. Self therapy with these methods may delay diagnosis, proper treatment and result in adverse consequences. Interestingly, playing the Didgeridoo, which is an aboriginal wind instrument, has been shown to improve the control rates for OSA. A well done study was published in the British Medical Journal in December 2005 showing this. The improvement was thought to be due to the use of circular breathing (which is the technique used to play the instrument) improving the muscle tone of the airway.

What is important to remember about snoring?

Although snoring is common, one should not assume that it is entirely benign. It is important to be aware of the symptoms of OSA and if OSA is present, diagnose it early by doing a sleep study. If OSA is present, an informed decision should be made on the treatment approach, especially if a potentially irreversible treatment like surgery is considered. If the sleep study is negative for OSA, Primary Snoring can be left untreated as long as it does not cause social problems.