Sleep Apnea Types: What Is Complex Sleep Apnea?

giugno 26, 2020

Sleep Apnea Types: What Is Complex Sleep Apnea?

Many have heard the two most spoken about Sleep Apnea types: obstructive and central. However, did you know that there is a third type? Below, we introduce you to Complex Sleep Apnea and give you all the information you need to know to recognize this form of Sleep Apnea and how it is caused. 


What Is Complex Sleep Apnea? 

Complex or Mixed Sleep Apnea was only recently discovered in the field of sleep medicine after being diagnosed in an individual in 2006. As the name suggests, it is in fact the presence of both OSA and CSA at the exact same time. 

This type of Sleep Apnea occurs in an individual who previously presented symptoms of Obstructive Sleep Apnea (OSA) which then progressed into Central Sleep Apnea (CSA) as a result of CPAP therapy treatment. This is a lot to unpack and complex to understand - hence the name. 

While most cases of CPAP therapy are successful in treating the symptoms of OSA in some very rare cases, it can cause an individual’s breathing pattern to change. This breathing change can then cause breath holding which triggers CSA. It is important to note though that only when a certain number of CSA events happen during CPAP therapy is it diagnosed as Complex Sleep Apnea. 

According to sleep specialists, an individual must have at least five CSA apneic events per hour for Mixed Sleep Apnea can be diagnosed. It is believed that CSA apneic events are quite common at the beginning of CPAP or BiPAP therapy for OSA. However, fortunately, in most cases, these events stop once patients become used to Sleep Apnea treatment. 

It is believed that only 2% of people that are diagnosed with OSA go on to develop Complex Sleep Apnea. 


How Is It Caused And What Are The Risk Factors? 

The exact causes of this type of Sleep Apnea are not yet fully known. While it has been linked to the use of CPAP therapy, some studies suggest that there are certain individuals who may be predisposed to developing Mixed Sleep Apnea due to instability in breathing control. 

Some sleep specialists also suggest that those who have difficulty managing sleep, such as those with insomnia, may also be at a higher risk of developing OSA and CSA at the same time. 

It is important to note that it is not only CPAP therapy that has seen a trigger of this condition. Other forms of treatment for Sleep Apnea such as surgery and oral appliances have been reported as another risk factor for developing this sleep disorder. 


Treatment Options: What Is The Best Way To Treat It

While medical professionals are still developing ways in which to treat Complex Sleep Apnea effectively, most sleep specialists believe that patients should use a CPAP machine with a low-pressure setting to reduce the likelihood of developing CSA apneic events during treatment for OSA. 

Identifying the underlying causes will also be beneficial for improving compliance with CPAP therapy and possibly reducing the risk factors that lead to Complex Sleep Apnea such as ensuring that masks fit correctly and that your CPAP pressure setting is too high

As development in this area of sleep studies continues to unveil new revelations in regards to Sleep Apnea types, the good news is that in 98% of cases individuals who experience OSA and CSA at the same time get relief from adequate treatment. 

If you have OSA and are not happy with your Sleep Apnea treatment it is important that you speak with your sleep specialist immediately. They will help you determine whether there is anything being missed or whether your prescription is not right for you. 

For more information on the other Sleep Apnea types, Obstructive Sleep Apnea and Central Sleep Apnea, browse our Better Sleep Blog or reach out to our team of experts.

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