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Sleep Apnoea

As mentioned above sleep apnoea refers to snoring plus stopping breathing repeatedly after having fallen asleep. This is usually also associated with low oxygen level in the body.

How common is Sleep Apnoea?

Sleep apnoea is common. In Newcastle it affects approximately 4 in 100 people. It can start at any age but it is particularly common after the age of 40. Men are more affected than women with 4 men for 1 woman. The difference tends to diminish after menopause.

What causes Sleep Apnoea?

During sleep the muscles in the body go "floppy". This applies to all muscles including the ones in the throat. Sometimes the floppiness is so great that the lining of the throat tends to collapse, the air stops going through completely or almost completely and the person stops breathing. Stopping breathing can persist for a few seconds up to 20-30 seconds. As soon as the oxygen starts falling, however, the body has a warning mechanism, which tends to wake the person. The person can wake completely, occasionally with a choking feeling lasting 1-2 seconds. However, most of the time the person goes from a deep sleep to a light sleep, to allow the person to breathe and then back to deep sleep again (but does not wake up fully). Therefore he/she is not aware of it. For example, if the person stops breathing 40 times/hour the sleep tends to be disrupted 40 times/hour. The consequences being that, even though a person may be asleep for 10 hours, he/she never stays in a "deep resting sleep". This results in waking up unrefreshed, being tired and sleepy during the day. The memory starts to fail; the person is unable to do his job properly. The mood can also change and the person can become more irritable or snappy and cranky.

Importance of Sleep Apnoea

People may be labelled lazy and occasionally even being considered having a psychiatric disorder. More importantly the daytime sleepiness caused by sleep apnoea can result in job loss, car accidents and job-related accidents and sometimes in family problems.

Medical conditions associated with Sleep Apnoea

High blood pressure can be made worse by sleep apnoea. It is not uncommon that once sleep apnoea is treated the high blood pressure becomes either controlled or more easily controlled by medication. Sometimes a person has to reduce the amount of medications he takes when sleep apnoea is treated.

Impotence and lack of sexual drive are also a common problem in patient's with sleep apnoea.

Irregular heart beat and possibly increased risk of heart attack and stroke are also associated with sleep apnoea.

Factors which predispose to Sleep Apnoea.

The most important single factor which affects sleep apnoea is weight. A person who is only a snorer (noisemaker) and puts on 10-15kg in a short period of time is likely to progress and develop sleep apnoea. By the same token reduction of even 5-10kg can reduce the amount of stopping breathing during sleep.

Alcohol, particularly in the few hours before going to bed, is likely to make sleep apnoea worse.

Certain medical conditions such as lack of thyroid hormones and lack of growth hormones can also make sleep apnoea worse and sometimes sleep apnoea disappears following correction of these abnormalities.

The presence of a chronically obstructed nose, as well as large tonsils make sleep apnoea more likely to occur.

Severity of Sleep Apnoea

The severity of sleep apnoea depends on the number of apnoea's (the numbers of times the breathing stops) and the degree of lack of oxygen which results from it. Stopping breathing up to 5 times/hour is still considered normal. Stopping breathing completely and partially up to 15 times/hour is usually considered not particularly harmful. However, as the number of times the breathing stops increases, so does the severity of the condition, and the complications which come with it. Sleep apnoea is considered severe when a person stops breathing 50 or more times/hour. Moderate sleep apnoea is considered between 30-50 times/hour and mild sleep apnoea is below 30 times/hour. These, however, are only guidelines used by doctors.

From a patient's point of view the severity depends on how sleep apnoea affects their daytime function. For example; sleep apnoea (stopping breathing 30 times/hour) may not be terribly relevant in a person who can stay home and can rest during the day. However, it may become much more important to a train or taxi driver who is at risk falling asleep in a high-risk occupation.

Treatment of Sleep Apnoea

The treatment can be divided into groups.

1. What the patient can do.

The single most important step that the patient can take is weight control. Weight reduction is usually a very effective way in reducing the amount of stopping breathing. Avoidance of excessive alcohol and in particular alcohol in the evening hours is another important step. Similarly, avoidance of sleeping tablets and sedatives (tablets for anxiety, antidepressants) would also be useful.

2. Medical treatment.

Correction of the lack of thyroid hormones or other hormones can be an important step.
The current treatment for sleep apnoea is with a mask, tightly applied to the nose of the patient, which pumps air through the nose and keeps the back of the throat open like a pneumatic splint. This prevents the soft part of the throat from collapsing. This treatment is called nasal CPAP (nasal continuous positive airway pressure). It is usually successful in the majority of people. The treatment is very safe and virtually free of side effects. It is, however, somewhat primitive and intrusive and only approximately 60-70% of the patients who need treatment are able to tolerate it. Research for other possible treatments are underway.
Mouth guards for snoring and mild sleep apnoea are similar to mouth guards for treating people for grinding their teeth or for protecting teeth during sport competitions.
The difference is that both upper and lower jaws are covered by the mouth guard used for snoring. Oral appliances (mouth guards) work by forcing the lower jaw in a forward position. The degree of forward movement is important to treatment success. Currently mouth guard are accepted treatment for snoring and mild obstructive sleep apnoea (mild obstructive sleep apnoea = stopping breathing less than 30 times /hour). Success is obtained in 60 to 70 % of patients. It should be noted that weight reduction remains a very important part of treatment in snoring and mild sleep apnoea. Mouth guard can also be used in severe sleep apnoea when weight reduction cannot be achieved or nasal-CPAP cannot be used or tolerated.

Side effects of mouth guards: Excessive salivation and transient teeth discomfort in the morning is reported during the initial use of oral appliances. It is important that mouth guards are made respecting upper and lower jaw alignment (byte), otherwise temporal mandibular joint discomfort may result.

Oral hygiene: before a mouth guard is used it is important that dental restoration is undertaken by your dentist. It is usually not possible to use a mouth guard if total denture is fitted.