Obstructive sleep apnoea, known as OSA, is a condition when people stop breathing while they are asleep. Tissue in the airways relax, the airways close and the person stops breathing. When this happens, the brain wakens them to begin breathing again. This cycle can repeat hundreds of times a night, and often the sufferer is unaware of the problem.

The condition can affect men or women at any age, but is more common in males, particularly when overweight, with Maori and Pacific Islanders shown to be more at risk.

The Thoracic Society of Australia and New Zealand report the problem, which research indicates affects about 16,000 adults and two per cent of children, costs taxpayers $40 million per year. This figure is made up of lost production, medical costs and increased risk of accidents and other illnesses such as hypertension, diabetes, cardiovascular disease and respiratory failure.

How do you know if you have OSA?

Some of the symptoms of OSA include:

• waking in the morning feeling tired and groggy
• having headaches and feeling sleepy during the day
• difficulty concentrating and finishing tasks
• being overweight
• having high blood pressure
• stopping breathing during sleep for 10 seconds or longer (your partner can report this)
• waking up frequently for no apparent reason
• getting up two or three times a night to urinate.

A detailed history of the problem and examination of the throat for signs of narrowing can help diagnose OSA, but the key symptom is snoring, particularly in conjunction with daytime or early evening sleepiness. It may often be helpful for the person's spouse or partner to be present, as they can explain what happens to the person during sleep.

Tests may be used to confirm the diagnosis of OSA. Polysomnography is the most comprehensive medical test available, but is not usually required to identify patients who will respond well to treatment. Often, a simple home monitor can be used to assess long-term risk and treatment can be initiated based on clinical presentation of snoring and tiredness.

Managing OSA

Dental appliances, such as special mouthguards and other devices, assist some people with very mild OSA but are generally intended only for those patients who have snoring without symptoms of associated sleep disturbance.

Surgery might be helpful when specific abnormalities, such as enlarged tonsils or a blocked nose, are found that are contributing to the condition. However, results of surgery in patients without specific abnormalities are often disappointing if there is any degree of OSA.

Continuous positive airway pressure (CPAP)

Continuous positive airway pressure (CPAP) is the gold standard treatment, and modern CPAP technology has become unobtrusive and comfortable enough that many thousands of New Zealanders use it to control not only OSA, but also simple snoring.

This is the most common treatment for OSA, but is increasingly being used for the treatment of sleep disturbance arising from snoring, and even straight snoring. It involves the use of a small bedside flow generator which increases the air pressure in the upper airway via tubing and a mask fitted to the nose.

The slight increase in air pressure effectively splints the airway so it remains open as it is when awake. CPAP is the only treatment for snoring and sleep apnoea which is guaranteed to work.

Many people find they feel much better within a few days of commencing CPAP, as they get the benefit of deep restorative sleep that they previously lacked.

If you have a sleep problem, you should seek medical advice if:

• you have had insomnia for months
• lack of sleep is interfering with your ability to function normally during the day
• you have early morning waking, mood changes or feel under stress
• you wake often to go to the toilet (for men, this may be a sign of prostate problems)
• you are being woken by pain
• you are taking prescription medicines that are interfering with your sleep
• you have untreated respiratory, cardiovascular or gastrointestinal disease symptoms.

See also Sleep - what is it? and Sleep disturbances.

Original material provided by everybody. Reviewed by Bryn Sparks, sleep physiologist, Sleep Well Clinic, August 2008.