This is NOT medical advice; everything I say here is my experience and should not be taken as medical advice; please ask your doctor if you have questions about your medications and your Sleep Apnea.
Secondly; I am sure there is a thread about this somewhere, but I want to share my experience in hope that it can help someone else and to bring it to the front of mind for some other posts I have been following.
My Story:
I have been on CPAP for over 2 years, and in that time I have had a DreamStation APAP and a Resmed APAP and never could seem to understand how to get my AHI to below 5… I am always 12 or above (mostly centrals; so i'd have like an AHI of 21 which was made up of 3 OSA, 7 HA, 11 CAI).
As a Arthritis sufferer, I have been on an off a number of different medications. This one particular medication I was put on, I was on it for about 8 months before I was diagnosed with Sleep Apnea... I wish I had have been smarter back then - but at the time I was vulnerable, I wasn't aware of my sleep apnea (re-phrase I wasn't diagnosed with sleep apnea) and I had been suffering from chronic pain for a lot longer than I care to admit so I was willing to try anything (I should have researched it first, a lesson I have since learnt).
Fast forward 12 months, I had pneumonia and as part of the investigation, the respiratory doctor determined that I should have a sleep study, the study showed that I had obstructive sleep apnea (moderate) and I was started on an APAP machine.
I had a very bad experience, I had an AHI that would fluctuate from one day to the next, AHI of 5 or 6 one day, then an AHI of 12 to 32 the next; it was all over the shop, so the doctor increased the pressure I was on to 10-20 and the 95% pressure would always be almost 20 and my AHI's were rubbish. I tried different EPR settings, I tried lower pressures, I tried different machines... I tried everything I read on here and more… but my centrals would always dominate: at least X4 of my OSA value.
I think I found - PART - of my problem through accident/coincidence.
The medication I have been taking for my arthritis for years isn't working, I am still in pain and the relief the medication gives me is not worth the side effects, I gave it a good try (1 year 5 months, 26 days) but I decided that it isn’t managing my symptoms and I was only taking it because I would get huge withdrawals if I stopped taking it…. So I decided that I was going to stop taking the medication (AMA), however with a 32 hr half life it takes 3 days for a single dose to get out of your system, and 1-4 weeks for the withdrawals to subside… I tried to quit cold turkey, it was hell, so I researched how to do it properly and started a very aggressive taper regime, to slowly - but aggressively - get the damn thing out of my system.
So far over the last 4 weeks I have managed to cut down my dose (against medical advice - so everything I am saying is an opinion and a story of my experience NOT medical advice), I have managed to cut down from 16mg a day to 4mg a day over the last 4 week... absolute HELL, the withdrawals are horrendous; If only I knew I would NEVER have touched the S**t, and I am in constant pain while I find an alternative treatment methodology...
BUT…
... my average AHI has dropped - specifically - my Centrals have dropped - significantly - over the last week my centrals have averaged 3.9 per hour compared to my previous average of 9.7 - It doesn't look like the medication is what is causing me to have Central Apneas as my centrals started to show up about 3 months into my treatment and I was on the medication for over 7 months before I started CPAP treatment (and there's evidence of me having sleep apnea going back to 2003 so its not medication induced apnea).
In this case I was prescribed Buprenorphine for chronic back pain and arthritis; Buprenorphine is a partial optiate agonist, it is supposed to have a ceiling effect that means that it is supposed to be less addictive and have a decreased impact on respitiory depression in comparison to primary or full agonist opiate like Codiene, Oxycontin etc. In my case its very hard to determine if the Centrals are PRIMARILY caused by drugs or not - as I was ok for 4 months before the centrals started to show up on the machine, by that I mean I was using the APAP machine for over 4 months with OSA's dominant before I started to see Centrals >5 creep in and then become consistently a problem where almost every night in the last 6 months I have had centrals >5 every second day (usually 9+).
However during the last 3 weeks; since I have decreased my medication down by 3/4 (from 16mg to 4mgs) the centrals I have been experiencing have dropped by about 1/2.
So my point is...
Do your own research into the medications you are taking and what effects they can have on your sleep apnea because sometimes; something that is as obvious as a medication you are taking could be causing unnecessary problems that can be overlooked. I told the doctor about all my medications, gave the doctor a referral with all my medications on it, I took in updated health summaries every 3 months when I would go for a check-up to try and and get advice as to how to improve my situation, but either the doctor didn’t know or didn’t understand what the medication I was and on was and what risks it has.
Anyway, that’s my 2c, take back control of your own health.