Sleep apnea occurs when the walls of the throat come together during sleep, blocking off the upper airways. Breathing stops for a period of time (generally between ten seconds and up to one minute) until the brain registers the lack of breathing or a drop in oxygen levels and sends a small wake-up call. The sleeper rouses slightly, opens the upper airway, typically snorts and gasps, then drifts back to sleep almost immediately.
In some cases, the person suffering from sleep apnea doesn’t even realise they are waking up. The pattern can repeat itself hundreds of times every night, causing fragmented sleep. This leaves the person feeling unrefreshed in the morning, with excessive daytime sleepiness, poor daytime concentration and work performance, and fatigue. It’s estimated that about five per cent of Australians suffer from this sleep disorder, with around one in four men over the age of 30 years affected.
Degrees of severity
The full name for this condition is obstructive sleep apnea. Another rare form of breathing disturbance during sleep is called central sleep apnea. It is caused by a disruption to the mechanisms that control the rate and depth of breathing. The severity of sleep apnea depends on how often the breathing is interrupted. As a guide
- Normal sleep – fewer than 5 interruptions per hour
- Mild sleep apnea – between 5 and 15 interruptions per hour
- Moderate sleep apnea – between 15-30 interruptions per hour
- Severe sleep apnea – more than 30 interruptions per hour
Symptoms of sleep apnea
People with significant sleep apnea have an increased risk of motor vehicle accidents and high blood pressure, and may have an increased risk of heart attack and stroke. In the over-30 age group, the disorder is about three times more common in men than women. Some of the associated symptoms include:
- Daytime sleepiness, fatigue and tiredness
- Poor concentration
- Irritability and mood changes
- Impotence and reduced sex drive
- Need to get up to toilet frequently during the night
Obesity is one of the most common cases of sleep apnea. Other contributing factors include:
- Alcohol, especially in the evening – this relaxes the throat muscles and hampers the brain’s reaction to sleep disordered breathing
- Certain illnesses, such as reduced thyroid production or the presence of a very large goitre
- Large tonsils, especially in children
- Medications, such as sleeping tablets and sedatives
- asleep apnea congestion and obstruction
- Facial bone shape and the size of muscles, such as undershot jaw.
Treatment for sleep apnea
Treatment for sleep apnea relies on changes to lifestyle, including losing weight and cutting down on alcohol. Any contributing medical condition, such as low production of thyroid hormone, also needs to be corrected. Any surgical conditions such as large tonsils should be corrected.
The most effective treatment available is a mask worn at night that prevents the throat from collapsing by transmitting increase air pressure to the collapsible segment of the throat. This is called ‘sleep apnea continuous positive airway pressure’ (CPAP). The key to this treatment is finding a mask and machine that match the needs of a given individual with sleep apnea.
Another treatment is the use of a mouthguard (or oral appliance or mandular advancement splint). Mouthguards work by holding the jaw forward during sleep. When properly made, they can be effective for mild to moderate sleep apnea.
Although not always effective, surgery to the palate and base may be useful when other therapies fail. The types of surgeries are best undertaken by otolarygologists (ear, nose and throat surgeons) who take a special interest and have had training in sleep-related surgery