Sleep Apnoea: The Cost
It doesn’t take a rocket scientist to recognise that sleep apnoea is on the rise. Around 1 in 20 Australian adults has been diagnosed with sleep apnoea (that is a staggering 775,000 adults), and nationally the cost of treating sleep apnoea is between $400 and $500 million. The cost of devices for sleep apnoea alone (mainly CPAP machines) is around $80 million per year. However, the real incidence of this disorder is thought to be much higher than 1 in 20, as many sufferers remain undiagnosed, and the indirect costs of this disorder due to lost work time due to fatigue, other health problems that develop as a result of sleep apnoea, and the cost of accidents due to fatigue (sufferers are 2-7 times more likely to be involved in a motor vehicle accident) raises the real cost of sleep apnoea many times over.
In terms of health, sleep apnoea increases the risk of arrhythmia, coronary heart disease and heart attack, high blood pressure, congestive heart failure and stroke.
The Problems with CPAP
A recent study looking at the effect of treatment with CPAP (continuous positive airway pressure) and the incidence of further health problems has shown that compliance with CPAP does not reduce the risk of heart attack and stroke. It does however reduce fatigue, it does reduce the risk of motor vehicle accidents, and remains the most successful conventional therapy for sleep apnoea for those that can comply with it. Unfortunately a good percentage of the $80 million that Australians invest in CPAP machines each year ends up under the bed or in the back of the wardrobe because so many sufferers find CPAP difficult to adjust to. CPAP therapy works by a wearing an airtight mask over the nose and mouth (or just the nose with a chin strap to keep the mouth closed) and then delivering a constant stream of air to the mask from a small pump located beside the bed. Sleep apnoea sufferers often find this is difficult to adjust to – with complaints ranging from dry eyes (caused by leaks around the mask), dry irritated airways, bleeding nose, sleep disturbance from the noise or discomfort of the tubing, and the social inconvenience of looking like Hannibal Lector every night. Another difficulty is that treating obstructive sleep apnoea with CPAP sometimes leads to the development of central sleep apnoea (CSA). When this happens it is diagnosed as “Treatment Emergent CSA.” Unfortunately central sleep apnoea does not respond as well to CPAP therapy.
As CPAP is not a cure for the disorder, but rather a symptomatic treatment, the use of CPAP is needed for the lifetime of the sufferer. The discomfort associated with CPAP plus the requirement to comply for a lifetime means that compliance with CPAP therapy is troublesome. The medical definition of compliance with CPAP is that the sufferer wears the CPAP mask 4 hours a night for 70% of all nights – not a rigorous definition of compliance by any stretch of imagination. However, various studies show that compliance, even with such a generous definition, falls steadily over the years after diagnosis of sleep apnoea. Initial rates suggest that around 4 in 5 persons are compliant, and over five years this steadily falls to 3 in 4, and in some studies even as low as 1 in 2. The most successful conventional treatment for CPAP is not very successful at all. Fortunately this is an alternative, and this alternative treats the cause, not just the symptoms.
The Cause of Sleep Apnoea
Many sleep specialists now recognise that the driving cause of central sleep apnoea is a lowered level of carbon dioxide in the blood caused by over-breathing. It is also recognised by sleep specialists that lowered levels of carbon dioxide play a significant role in obstructive sleep apnoea. The over-breathing that results in the sound of snoring works to lower the pressure of carbon dioxide in the lungs (3% – 6.5%) to equalise it with the level in the air we breathe (0.03%). This is not a good outcome, as carbon dioxide is an essential substance in the human body with a range of beneficial effects. It works to:
- Keep the pH of the blood plasma in the necessary range (7.35 – 7.45) for necessary chemical reactions
- Relax smooth muscle
- Open (dilate) airways
- Open (dilate) blood vessels
- Allow the bond between oxygen and haemoglobin to break so that oxygen can be delivered to the cells in the tissues of the body
Thus, lowered carbon dioxide levels during sleep can cause a range of symptoms in the sufferer.
Carbon Dioxide – The Breathing Driver
During the day there are several mechanisms in the body that drive the breathing process. During sleep some of these are inhibited, meaning that the main driver for breathing during sleep is the level of carbon dioxide in the blood. Changes in blood oxygen levels too, can be a driver to breathe, but generally only if the oxygen pressure falls below 70%. The breathing centres of the body are much more sensitive to rises and falls in carbon dioxide than oxygen. When carbon dioxide is chronically lowered the breathing centres become even more sensitive to carbon dioxide, resulting in an increased breathing rate to ride the body of carbon dioxide, hence a chronically lowered level of carbon dioxide in the blood. During episodes of increased breathing during sleep the increased pressure in the airways causes the airway to collapse, causing obstructive sleep apnoea. Not until the carbon dioxide level rises to normal levels does the sufferer wake with a start (not usually remembered later) and begin breathing again. By this time oxygen levels have usually dropped significantly.
How Breathing Retraining Works
There are no current devices or medications known to safely correct over-breathing and/or increase CO2 levels in the blood back to normal levels. (If there was you could be sure that there would be a rash of studies by medical and pharmaceutical companies to develop and patent such a device or medication, and we would hear a lot more about the real cause of sleep apnoea – lowered CO2!). Because there is no patentable cure there is a heavy reliance on symptomatic treatment using devices such as CPAP machines. However thousands of people have now found relief from sleep apnoea through natural techniques involving breathing retraining and management of dysfunctional breathing habits. This is because (as scientists have increasing discovered in the last 50 years) the brain is plastic – it can be retrained. Dysfunctional breathing over time moves the CO2 blood level progressively downwards, eventually and periodically dipping it below the level that is required to stimulate breathing, particularly at night when the body is most reliant on CO2 levels to stimulate breathing. However, as the breathing centres are retained to tolerate higher levels of CO2 and faulty breathing habits corrected, the occasional and periodic dips in CO2 no longer drop the CO2 level below the level required to stimulate breathing. Hence the apnoea episodes are reduced or stopped. For this reason many sleep apnoea sufferers have retrained their breathing habits and no longer suffer with sleep apnoea.