The big snore
Sleep apnoea affects more than 24,000 New Zealanders. Rose Miller explains this common condition that can have major implications for health.
Snoring may be the butt of many a joke, but for a lot of New Zealanders it’s no laughing matter. And it’s not just a problem for those who have to listen to the noise – snoring can have serious implications for the snorer’s wellbeing, too.
Snoring is a key symptom of obstructive sleep apnoea (OSA), a chronic and progressive sleep disorder with potentially serious health consequences.
During deep sleep the muscles in our throats relax. For someone with OSA, the muscles become so relaxed that part of the airway is closed off and the person stops breathing. The level of oxygen in the blood drops, and the sleeper will choke and gasp then wake up for a moment and begin to breathe again, quickly falling back to sleep and rarely remembering waking. This can happen hundreds of times a night, and the moments without oxygen might last up to or over one minute.
A person with OSA may often have no idea they have a problem – a family member or bed partner might be the first to notice signs of sleep apnoea. They may still feel sleepy when they wake, and have a headache and dry throat. Daytime sleepiness is one of the most common symptoms and sufferers may often need to take daytime naps.
Someone with OSA may also experience problems with their memory, may feel grumpy and irritable, have mood changes, morning headaches, and have difficulty concentrating. They could have chronic exhaustion and lose interest in sex. Some of these symptoms can be put down to other causes, such as stress, which is why OSA can often be missed.
OSA affects about 9% of men, 4% of women, and 3% of children between 2 and 12 years of age in the general population. OSA is most common in men over 50.
It is more common if a person is overweight.Excess weight on the outside of the throat increases pressure on the inside of the throat, which narrows the airway. That being said, while being overweight is commonly associated with OSA, up to 20% or more who have been diagnosed with OSA are not overweight. Other risk factors include alcohol, and taking tranquillisers or sleeping tablets.
Left untreated, sleep apnoea has been linked to high blood pressure, heart disease, stroke, memory loss, obesity, and insulin resistance, a precursor to type 2 diabetes. The good news is that successful treatment (see panel) may reduce the risks of these ailments.
What is less well known is the possible association between OSA and type 1 diabetes. OSA is prevalent in those with type 1, but more studies are necessary to understand the link.
Lifestyle changes will be recommended for milder OSA cases. The most significant thing you can do is to try and lose weight – even a small loss can improve symptoms. Other recommendations include avoiding alcohol for at least a few hours prior to going to sleep. Don’t use sleeping tablets or tranquillisers, and try to sleep on your side rather than on your back.
A specially designed dental appliance or device can help to hold the jaw and tongue in a particular position to help maintain an open airway. These need to be fitted by a specialist dentist or orthodontist and are most effective in cases of mild OSA.
Continuous positive airway pressure (CPAP) is the most common treatment for OSA. It involves the use of a pump that delivers low-pressure air into the airways via a mask fitted to the nose. It is worn during sleep and delivers enough pressure to keep the airway open.
Surgery may be an option to address specific abnormalities that contribute to the airways obstruction, for example removing tonsils and adenoids, correcting abnormalities in the nasal passages, and removing excess tissue from the back of the throat or tongue. Surgery for OSA, though, is rarely performed.
If you think you might have symptoms of sleep apnoea, see your GP.