[Diagnosis] Help interpreting diagnostic report

[rleaman]

Hi, I am a new forum member and new to sleep apnea in general. Thanks for the great resource, already very helpful.

I've been having some trouble with my doctor not giving me enough information, with some of it contradictory. I would like to ask for help interpreting the diagnostic report attached, which shows the results of my home sleep study. 

My interpretation is that I have sleep apnea, since it shows an AHI of 10.0. Looks like it is about 3x worse on my back, suggesting positional apnea is a big problem for me. My average blood oxygen is probably fine (94%) but I spent 19 minutes at less than 88%; that tells me that whatever issue I have is intermittent (possibly suggesting positional again).

I want to check the interpretation of the "Apnea Index" line in the middle: it seems to show that the 3.6 apneas per hour listed in the first row (Events Index), that 0.4 are obstructive and 3.2 are central. I'm not sure why the doctor diagnosed me with obstructive sleep apnea if my apneas are mostly central.

Any advice, interpretations or informed disagreements welcome. Thanks!

[OpalRose]

Obstructives are 0.4, Central 3.2, and Hypopnea 6.4 (This adds up to 10 AHI.)

It seems common for doctors to label the results as Obstructive. Sleeping on your side would more than likely cut down on apneas, but that's not easy to do. Also, Hypopnea can also be disruptive to sleep along with Flow Limitation, Snores and Reras.

[Crimson Nape]

Usually, you must be over an AHI of 20 before treatment will be offered. Everyone has a higher incidence of apnea events while in the supine position. This is because your throat muscles relax while asleep and gravity helps collapse the airway. Sleeping on your side is the preferred position to reduce a lot of these apneas.

[Geer1]

Do you have the other pages (note this page says 1 of 3). One of the pages should have charts and it would be interesting to see when your oxygen levels were low and if it corresponds with apnea, hypopnea etc.

Your ahi of 10 is mild, treatment of such cases is only usually done when symptoms largely align with apnea (daytime sleepiness, snoring etc). Your time below 88% is larger than I would have expected based on your results so that is the main thing that caught my eye. As mentioned a
I am curious if the graphs would help explain this.

You are right that apnea was mostly recorded as central. Note that some of these might have been falsely flagged events as this machine is not capable of determining if you were asleep so if you held breath for 10 seconds while awake then it can show up as a central apnea. 3.2 is at the higher end of ahi that can be caused by falsely flagged events but it is possible especially if you slept poorly due to having equipment hooked up so just something to keep in mind. However if your desaturation periods were occurring during these central apnea then they are more likely to be real as falsely flagged events rarely have significant desaturations associated with them.

Although apnea looks mostly central being worse in supine position is supportive of an obstructive diagnosis. Regardless of whether this is obstructive or central in nature basic cpap/apap is the first recommended treatment. You should be able to trial a machine and the results of that test should be helpful.

[rleaman]

Thanks everyone for your replies. Interesting that treatment is usually only offered if AHI is greater than 20, though I definitely have had daytime sleepiness and more cognitive issues in recent months. The comments about obstructive vs central make sense. I did do a CPAP titration, which I just realized showed 0 central apneas, so maybe the instrumentation on the home study being less able to differentiate is part of the issue. The titration shows zero events (central, obstructive or hyponeas) at IPAP/EPAP of 8, 9, 10 or 11; I was prescribed CPAP with 9.0 (though I'm having real trouble with that - but it's a different issue, so I'll ask in a separate thread if needed).

As for this report, unfortunately, the only other page I have only contains the interpretation (Mild Obstructive sleep apnea worse in supine position) and a list of recommendations (CPAP, sleep on side, lose weight, etc). There are no graphs /charts. This doctor only gives the written reports upon request, and they tend to be low on details; one of my (many) complaints with this doctor.

Again, thanks everyone!

[Crimson Nape]

You are entitled to a complete copy of your sleep report. I would ask for it.

[Gideon]

An official diagnosis of central apnea requires a AHIc of 5 or greater. The hypopnoea were not split into obstructive and Central so with a CAI of 3 it is not. Classified as central apnea.

[ThinMountainAir]

Hi Rleaman, Your profile says you're using a Resvent iBreeze. If that machine allows you to use OSCAR then I highly recommend it. It will give you data from many nights rather than just the one night from your at-home study. Of course, it will give you data on how things are while on CPAP whereas the home study was without CPAP but if you're having centrals you'll have them even if on the machine. At least I think that's true, I'm not sure. I'm also fairly new to all this and there's a lot that puzzles me. For example, why did you have a titration study if you have an auto-CPAP machine and why were you put on a fixed pressure. I'm not actually asking those questions, I assume there's a good reason in your case. Regardless, welcome to the forum, I've been learning a lot from it (wit still a long way to go).