There's great relief from a CPAP, even though it directs more dirty air into our lungs than by not using a unit at all. Many simply guess it's a trade off; i.e., better to breathe dirty air than not to breathe at all. But wait. There may be a better answer.
Until now the discussion has been like the air itself, kind of hazy at best. One woman wrote:
"I don't know if this will be of any value to you but I recently started using a CPAP with a HEPA filter in the line along with a humidifier. What I have found is that in the morning I can actually breath better through my nose than I used to be able to before using CPAP. I'm thinking that the HEPA filter is taking out the mold spores, dog dander, etc and the humidifier is keeping my sinuses wetter and these are the reason for the improved breathing. All is not a bed of roses though because sometimes the machine seems to plug up my nose during the night."
The problem with using a CPAP alone, even if it is equipped with a HEPA filter, is that there's just too much dirt, dust, dander and other VOC's, gases, particulates and allergens in bedroom air, not to mention aldehydes and off-gassing elements in the room. When the CPAP draws from polluted bedroom air and aggressively directs the air into one's respiratory system, there's more pollutants for one's own body to have to filter.

The answer is to have a separate, qualified, professional air cleaner in the bedroom. The best bedroom air cleaner is made by Austin Air.
http://www.austinair.com .
Austin Air + CPAP = Relief from Apnea.
Austin Air is the leader in clean indoor air.