Snoring is a noise made by breathing which is caused by vibration of the soft tissues of the upper airway during sleep. It is common and can either occur without an association with a sleep-related disorder (known as primary snoring), or as a symptom of obstructive sleep apnoea (OSA).

It usually results from either complete or partial obstruction to the free flow of air through the passages at the back of the mouth and nose. Snoring is more common in men and in those that are overweight. It may be worse when lying on your back and can worsen with age. Recent study findings suggest that a narrow throat, which can be inherited, may also cause snoring and OSA.

Obstructive sleep apnoea is a condition characterised by repetitive episodes of not breathing (apnoea). These episodes are followed by gasping and choking noises resulting in a decrease in blood oxygen saturation (the amount of oxygen carried around the body).

It is characterised by excessive daytime sleepiness, morning headaches and unrefreshed sleep. In the long term there is an increased risk of stroke, high blood pressure and heart disease.

Snoring, if severe, may be associated with interrupted sleep and deprive the snorer of appropriate rest. Primary snoring is not associated with increased risk of cardiac disease. People may be unaware of the fact that they snore and it may only come to light when a partner complains about their interrupted sleep. It may even lead to marital dysfunction.

People who snore may suffer from:

Poor muscle tone in the tongue and throat. When the muscles are too relaxed the tongue falls back into the airway.
The airway can be obstructed by excess tissue in the airway e.g. by large tonsils, large tongue.

Obstructed nasal passages - this can occur in nasal rhinitis (inflammation of the lining of the nose) and can be caused by certain allergies.

Deformities of the nose or nasal septum (the division between the two nasal passages) may increase nasal resistance.
Being overweight. Those with bulky neck tissue may also be affected.
Snoring can be associated with hormonal conditions such as hypothyroidism (under active thyroid gland) or acromegaly (excess production of growth Hormone).

Diagnosis:

A full history and examination is taken. It is important to differentiate primary snoring from obstructive sleep apnoea. You may be asked to fill out a questionnaire about daytime sleepiness, unrefreshed sleep etc. If obstructive sleep apnoea is suspected then a sleep study may be undertaken. This records sleep patterns and requires an overnight stay in hospital.

Treatments

The aim is to prevent disturbance of the partner's sleep and to relieve the sleeper's embarrassment about his/her snoring. Here are some tips to help reduce snoring:

Lose weight; this also confers other health benefits.
Sleep on your side.

Avoid cigarettes and alcohol. Smoking contributes to disordered breathing and alcohol worsens upper airway obstruction and decreases muscle tone.

If the problem is nasal rhinitis then nasal decongestants and nasal inhaled steroids may be prescribed.
Mechanical devices:

These are designed to keep the mouth open and increase the upper airway size during sleep. Some devices bring the jaw forward, some elevate the soft palate and some keep the tongue from falling back into the airway and blocking the airway. They are usually fitted by dentists.

The following devices are specifically used in the treatment of obstructive

sleep apnoea:

Continous Positive Airway Pressure (CPAP):

This is a machine which is attached to a mask which surrounds the nose and mouth. It blows air into the nose and keeps the airway open and unobstructed.

Biphasic Positive Airways Pressure (BiPAP) :

This machine blows air through a nose mask at two different pressures. When one breathes in, the pressure is higher and when one breathes out, the pressure is lower.

There is surgery available called uvulopalatopharnygoplasty which removes the uvula and excess tissue. The uvula is the fleshy part that hangs down at the back of the throat. The palato refers to the palate and pharyngoplasty is surgery to the pharynx (joins the windpipe and gullet).