I have been a CPAP user since last fall following my diagnosis of severe SA with a primary Central Sleep Apnea component.
I find my Obstructive Sleep Apnea to be pretty well controlled but the Central SA is a real wildcard. Never know what to expect.
I am interested in connecting with anyone who has a similar profile to compare notes.
Thanks!
At diagnosis with an AHI of 37, central sleep apnea was a minor component. Now, with CPAP treatment, central apnea has risen to form about 50% of the total AHI, with another 40% due to hypopnea, and the remaining 10% obstructive apnea. Currently my AHI is averaging about 3, so CPAP treatment has been very effective in reducing obstructive apnea. But, the central apnea, plus the hypopnea which I believe to be central in nature, remains a problem. But, with AHI under 5, it is considered acceptable. While it does, I do not plan to lose a lot of sleep (so to speak) over it.
If you have pure central sleep apnea then a CPAP is probably not going to work. An ASV is more appropriate. If you have both obstructive and central apnea that can be a difficult situation. Pressure tends to reduce the OA, while it increases the CA. What would be helpful if you gave more detail on what your AHI composition is, and what pressures you are using to treat it.
One of the best articles I have read on complex sleep apnea (both OA and CA) is at another part of this site in the Blog area. You can find it at this link. I would recommend reading it.
Hope that helps some, but if you post some more detail on where you are at, I may be able to be more specific.
Typically, of late, my composite AHI has been averaging between 3 and 4 (occasionally lower, occasionally as high as 7) over about 6 hours of sleep which seems to work well for me.
Generally my events are scattered thru the night with some stretches of early sleep being largely uninterrupted.
The overall AHI has typically consisted of a mix of obstructive, central, and hypopnea events with the CA component usually being the largest.
The CAs tend to mostly appear: (a) just as I am dropping off to sleep, (b) as I try to fall back asleep after waking during the night, and (c) most often in a flurry of events just prior to getting up (say during last 40m or so of night). These flurries can often consist of 10 or 12 events strung together over a brief period of a few minutes.
There seems to be a "handoff" issue from my waking breathing to my sleeping breathing in the patterns I've observed using Sleepyhead to view the data.
Does this help?
Yes, that is helpful. Sounds similar to what I suffer from, although I typically get a fairly event free first half of the night. You may want to zoom in on that flurry of events strung together. They can be Cheyne Stokes Respiration, although if your machine is a ResMed it should flag it. DreamStation calls it periodic breathing. Sometimes medications can be a problem. I suspect my beta blocker for blood pressure increases my CA event frequency, and I convinced my doctor to half the dose.
But I think if the AHI averages under 5 it is not going to get much attention from a sleep doctor. If you can't stay under 5 and it is almost all CA then an ASV may be worth looking into. At least that is my plan. Stick with my AirSense 10 AutoSet for as long as I can, and then hopefully get a prescription for an ASV. The disturbing part of central apnea is that if it is not drug related, it most often indicates cardiovascular issues. And they should always be investigated and treated on their own merit.
Thank you.
Yes, we appear to have a lot of similarities.
I too am currently using an AirSense 10 AutoSet.
I also take a BP med although mine is an Ace Inhibitor.
On occasion, maybe a handful over past the 8 months I've exhibited one brief episode of CSR during a night.
I am also under the care of a cardiologist, monitoring a minor MVP. Otherwise my recent tests revealed no other obvious cardiovascular issues.
Agree that at current AHI levels, while a drag, I am unlikely to get moved to an ASV.
I also take an ACE inhibitor (perindopril), but I don't suspect it is a problem.
One of the things you might want to think about is pressure. Over the months I reduced the maximum pressure and increased the minimum pressure until I only had about 1 cm difference. My theory based on a detailed review of the events recorded in SleepyHead is that the ResMed machine is chasing hypopnea events with more pressure. And, it is designed to do that, as it assumes a hypopnea event is caused by an obstructive flow restriction that does not go to a full obstructive apnea.
The problem is that the hypopnea event can also be caused by a reduced effort to breath, which is really central hypopnea. For these reasons I think it is of benefit to me to restrict the maximum pressure that the machine can go to, as increased pressure, at least in me, causes more central apnea. With this theory, I finally got to the point of trying a single fixed pressure (CPAP mode). It actually achieved a better AHI than even a narrow 1 cm pressure range in APAP mode. It does however takes long trial periods at different pressures to find the ideal. It would seem that one would just have to reduce pressure until obstructive apnea becomes a problem. I found it is not that simple. It seems even a single short obstructive apnea event can start a minute ventilation cycle which can result in multiple central apnea events. More pressure can cause centrals, and at some point less pressure can also cause centrals. So there is no sharp clear cut pressure which is obviously ideal. It just takes trial and error and a long time at a pressure to see how good or bad it is. As a check I also use total time in apnea as a measure. To me that is even more important than AHI.
I was running a pressure up to 15 cm in Auto mode, but now I use a single fixed pressure of 11 cm and get better results.
Hope that helps some,
Interesting you say this as what you describe is along the lines of what I was thinking of trying based on my own data analysis and what I have researched regarding CSA and air pressure. Thank you for sharing this.
Another factor I found increases my frequency of central apnea is using EPR. I originally used it at a setting of 3 when in Auto mode. I believe it increases the pressure in Auto mode and as a result increases CA's. Now I use it in AutoRamp only, and it shuts off when the ramp ends. I think that is one of the reasons I can now use the fixed pressure mode at a lower pressure.
Since the above was written I've enjoyed a good run of improved AHI's running in the approx 1.3 - 2.5 range. I still have "off" nights, never exactly sure why. Still, my off nights are considered "mild SA" according to the AHI tables.
When I do have off nights though, they tend to be as described above in my earlier post in the sense that I enjoy relatively undisturbed sleep for 5.x of the 6.x or so hours I tend to sleep, with a flurry of CAs in the last 40-60 minutes that raise say a 1.3 for the 5 hr segment to say a 3.0 for the night (i.e. the majority of the interrupts occurring as I drift in and out of sleep at the end of the night, never returning to deeper sleep).