Sleep apnea

What is sleep apnea?#

Sleep apnea (also known as obstructive sleep apnea, or OSA) is the common form of sleep apnea. It occurs when the throat muscles relax too much during sleep, so that breathing stops for a time before starting again. It is linked to a disruption of the mechanisms that control the rate and depth of breathing.

If you have sleep apnea, the walls of your throat collapse and narrow as you breathe in while asleep. As air tries to pass through the narrowed airway, it makes the tissues at the back of the throat vibrate, producing the sound known as snoring. Sometimes the throat collapses so much that not enough air reaches the lungs (hypopnea), or it blocks off completely so that no air gets through (apnea).

These partial or complete obstructions cause your breathing to slow or stop for a short time, generally between 10 seconds and up to one minute. They are sometimes called episodes or interruptions. When they happen, the brain receives signals that something is wrong and briefly rouses itself from sleep. Most people are not aware of these arousals, but the pattern can repeat hundreds of times a night, leaving your sleep fragmented.

This can leave you feeling unrefreshed in the morning, with fatigue and sleepiness throughout the day that contributes to poor concentration and reduced work performance.

Who gets sleep apnea?#

Anyone can get sleep apnea. It is estimated that about 5 per cent of adults have it, with around 1 in 4 men over the age of 30 affected. In the over-30 age group, the disorder is about three times more common in men than in women. People with narrow throats are more likely to have sleep apnea and to snore as their throat muscles relax.

How severe is it?#

The severity of sleep apnea depends on how often your breathing is interrupted. As a guide:

• Mild – up to 15 interruptions per hour.
• Moderate – between 15 and 30 interruptions per hour.
• Severe – more than 30 interruptions per hour.

Symptoms#

Symptoms of sleep apnea may include:

• regular periods of reduced or absent breathing during sleep, often with loud snoring and/or gasping for air
• poor-quality sleep and daytime sleepiness or fatigue
• poor concentration, poor memory and slow reaction times
• irritability and mood changes, depression or anxiety
• dry mouth and headaches
• needing to get up to use the toilet frequently at night
• reduced sex drive (libido) or impotence (erectile dysfunction)

Driving and other safety#

Sleep apnea can affect your ability to drive, and people with significant sleep apnea have an increased risk of motor vehicle accidents. Many driving and licensing authorities recognise that certain sleep disorders, including sleep apnea, can affect fitness to drive.

You may be legally required to notify your licensing authority of any serious or chronic medical condition that may affect your ability to drive, and failure to do so may affect your insurance cover. People with sleep apnea are usually assessed on a case-by-case basis and may be asked to provide medical reports on the severity and treatment of their condition. In some cases a conditional licence may be issued until the sleep apnea is adequately treated.

People with sleep apnea should also think about safety in other situations, such as at work, where falling asleep could put others in danger – especially if the condition is severe and has been untreated for a long time.

What causes sleep apnea?#

Contributing factors for sleep apnea include:

• being overweight or obese – fat inside the neck surrounds the throat and makes it narrower
• age – throat muscles tend to relax more during sleep as people get older
• alcohol, which also relaxes the throat muscles during sleep, leading to apnea and snoring
• certain illnesses, such as reduced thyroid production (hypothyroidism) or a very large goitre
• large tonsils and adenoids, which may cause sleep apnea in children
• nasal congestion and obstruction
• the shape of the facial bones and the size of the muscles, such as an undershot jaw
• certain medications, such as sleeping tablets and sedatives

Sleep apnea can also increase your chance of having high blood pressure, and may increase your risk of heart attack, stroke and abnormal heart rhythms.

How is sleep apnea diagnosed?#

If you think you or someone you know has the signs and symptoms of sleep apnea, see a doctor. If sleep apnea is suspected, you may be referred to a sleep specialist.

A sleep study is a medical test used to diagnose a range of sleep disorders, including sleep apnea. It looks at what happens while you sleep. You are attached to a portable machine, and monitoring leads placed on your body track your sleep through the night. Most sleep studies measure:

• breathing and snoring
• brain signals
• oxygen levels in the blood
• sleep position and limb movements
• heart rate

Sleep studies can be done at home or by staying overnight in a special sleep clinic, and are available through public and private health services.

Treatment#

Sleep apnea is a very treatable condition. Treatment can range from lifestyle changes to surgery. Any contributing medical conditions, such as low production of thyroid hormone or large tonsils, may also need to be treated.

Lifestyle changes#

The first line of treatment is making changes to your lifestyle, including:

• losing weight, in people who are overweight or obese – this may improve your sleep apnea and possibly cure it, and has other health benefits too
• cutting down on alcohol

Continuous positive airway pressure (CPAP)#

The most effective treatment available is a mask worn at night that delivers increased air pressure into the airway to keep the throat from collapsing. This is called nasal continuous positive airway pressure (CPAP), and it is the most common treatment for sleep apnea.

It is non-invasive and uses a small pump that blows air through tubing into a mask worn over the nose and/or mouth. The air pressure reaches the back of the throat and holds it open, even when the throat muscles have relaxed too much during sleep. The key to CPAP is finding a mask and machine that match your needs.

Dental devices#

If you have mild to moderate sleep apnea, an oral appliance such as a specially made mouthguard (for example, a mandibular advancement splint, or MAS) may help. These are designed to pull the lower jaw forward to create more room in the throat, though they do not prevent the throat collapsing during sleep. They need to be fitted by a dentist and worn whenever you sleep, and are also used to treat snoring.

Positional devices#

Some people only have sleep apnea when sleeping on their backs, and you may move around in your sleep without realising it. Attaching something to keep you off your back – such as a tennis ball sewn into a T-shirt or pyjama top – can help. Commercial positional devices are also available from some CPAP suppliers.

Upper airway surgery#

Surgery may be considered when other treatments have not worked. Surgery to the palate and base of the tongue may be suggested, especially for school-aged children and young adults. However, there is a limit to how much tissue can be removed, and surgery does not prevent the throat collapsing during sleep, so it may not be effective. Any surgery of this kind should be done by a specialist ear, nose and throat surgeon (an otolaryngologist). Your treating team can discuss your concerns and help you weigh up the benefits.

Sleep apnea in children#

Large tonsils and adenoids can block the throat during sleep and cause snoring. In some cases this is bad enough to cause obstructive sleep apnea. The more severe a child’s OSA, the more likely it is that removing the tonsils and adenoids will improve their health and quality of life.

A tonsillectomy for sleep apnea is considered if a child usually breathes noisily during sleep and has at least two of these related problems when they are not sick:

• struggling to breathe while asleep
• pauses in breathing during sleep
• gasping or choking during sleep
• persistent daytime mouth breathing
• daytime tiredness, or concentration or behaviour problems not related to other causes

Two out of three children with mild sleep apnea get better over 6 months without surgery. If your child is young, you may wish to wait 6 months before deciding whether surgery is an option.

Key points#

• Obstructive sleep apnea is the common form of sleep apnea.
• It is linked to a disruption of the mechanisms that control the rate and depth of breathing.
• In the over-30 age group, the disorder is about three times more common in men than in women.
• Large tonsils and adenoids may cause sleep apnea in children.
• Treatment may range from lifestyle changes to surgery.

Where to get help#