Opinion on Sleep Study

[dataq1]

see if her treatment appears to be adequate.

What she would like to know is ..... "treatment for what ? "

Does the second segment of her sleep study ( from about 3:10 to 6 am) establish that she has a medical necessity for Cpap therapy? 

(because it looks to me as if her 3 hypopneas (and associated desaturations to 89%) over a 3 hour period (HI~1) are well in the normal range of the general population)

She (and I, now that I understand the initial reason for the sleep study) is inclined to think that the sleep doc is being overly aggressive to acquire a new client.  

BTW, the doc who initially requested the study is not the sleep doc, but the sleep doc was the one who read the study and recommended the Cpap therapy.  (We also have learned that the sleep doc is a partner in the DME he assigned her to))

Anyway, I'm about to suggest to her that she does question the doctor that ordered the study, if for no other reason she should understand  the "why".

Finally, since you have faith in home studies, I'll suggest to her that she consider obtaining one of the several home studies that are marketed on-line.

[Geer1]

Not sure how you only counted 3 hypopnea. She had a minimum (the odd lines might be double events, hard to tell) of 2 apnea, 17 hypopnea, 17 cases of snore and nearly constant flow limitation in the ~2.5 hours from 3:30-6. Based on that she clearly has at a minimum mild apnea and SDB.

I am 90% sure these Resmed home studies are automatically scored by Resmed similar to how their CPAP machines score and record data and that the techs/doctors just look at the results and interpret them the same way we look at and interpret OSCAR data. I know this because in my case my AHI was just below the 15 minimum required for insurance coverage so they tried collecting a 2nd night of data and then sent the worst of the two in for manual scoring (cause both were under the 15 minimum and I refused to pay out of pocket).

As for how to proceed, for sure question the ordering doctor if she doesn't understand the reasons behind him ordering the test. If he doesn't have a good answer and she believes she doesn't have symptoms then ignore the study since it shouldn't have been ordered in the first case. If he does have a decent reason then imo she is best accepting that this data is accurate and moving on. 

Follow up home sleep studies aren't really going to do much other than prove SDB or create controversy if they don't (which any good doctor would say is due to the variability of apnea). I also doubt her ordering doctor is going to believe an on-line ordered home test over the clinic he regularly deals with. If she really thinks these results are wrong and she wants them refuted then I think the only way would be an in clinic PSG due to their higher accuracy.

[SarcasticDave94]

If I were to base my decision to treat or not with that chart given in post 1, I would consider getting ResMed AutoSet. AHI 11.1 was mentioned, which is the higher end of mild.

Obstructive and Central weren't too bad. Hypopnea, flow limit, and snoring were notably worse though, especially flow limits almost straight through.

If the person being tested chooses not to get PAP now, they'll likely need to be on it later. Being proactive and getting it treated now may not be a bad thing.

[dataq1]

If the person being tested chooses not to get PAP now, they'll likely need to be on it later. Being proactive and getting it treated now may not be a bad thing.

The patient has been on Autoset 11  now for 90 days with an average AHI of 1.17 (highest=4.5, lowest=0.2) with an average pressure of 9.3. She reports no improvement in sleepiness or other symptoms when comparing pre and post therapy. ( she says she had no complaints before she  started this experiment). Her Epworth sleepiness  assessment is unchanged.

What she questions is if the original sleep study was flawed.  (it is obvious that there was a problem with the pulse ox)

She is a very compliant patient (eager to follow dr's direction) but what is now on her mind is the prospect of having to use this Pap equipment for the rest of her life. 

(She has confided that she sees the potential of her sitting in a nursing home corridor at the age of 90 and having a aide attending to her mask and Pap equipment every time she nods off while watching Family Feud reruns in the afternoon - all because some doctor, who she never met, who has never examined her, placed his faith in a sleep study where some of the equipment wasn't working correctly).

Now this thread has drifted somewhat away from the original request to have others here express an opinion as to justification for requesting a new sleep study. - Her question (seems to me) centered on the fear that once having started Pap therapy (regardless if justified or nor) they can ever hope to get off therapy.  

So maybe it's time to begin a new thread about how to end therapy.

[SarcasticDave94]

I don't think another study will give what your friend is after. She wants to get ammunition to decide not to be on PAP because the study was wrong in some way in her mind. Some parts of that test maybe were inaccurate but the main wasn't lacking. She has Apnea, 11 AHI says so. And realize once diagnosed with Apnea unless it's very light it's a life issue and it's not going away on its own. Denial treats nothing.

I don't think another thread will change these facts. She wants to justify denying Apnea are an issue and wants to shelve CPAP. OK just do that then. But the fact that 11 AHI is there isn't going to change. She doesn't need our permission or support in pulling the CPAP plug. She's an adult, do whatever she's of mind to do, taking responsibility for one's actions.

---

Last thought about this that's seemingly going to feel off topic, you don't need to quote on every post. Just type your comments. Common board etiquette. Thanks.

[Geer1]

You stated her average pressure is 9.3 which appears to indicate that she has flow limitations or something driving her pressure up (I assume her minimum pressure is lower like 4 or 6 cm). If that is the case it is in agreement with her original sleep study which showed high flow limitation. If you are going to start a new thread it should be to post OSCAR data for review as that will tell us and her more than any old single day sleep study.  

Most people that go on CPAP are on it for the rest of their lives, SDB rarely goes away unless it is specific to something that can be fixed such as being significantly overweight, chronic nasal congestion issues etc. If there are no known issues that can be improved then the apnea is most likely related to narrow airways or flabby tissue that obstructs the airway. There are different forms of treatment for this but CPAP is the primary one with the best success, a mandibular advancement device (similar to a mouth guard) is one of the other more common treatments but similarly it would have to be used for the rest of her life (or until she switched back to CPAP).

If she thinks using CPAP is BS then she has the choice to be like many patients and discontinue treatment. It does appear that she has SDB but lots of people have SDB and don't use or need CPAP. AASM only recommends treating mild apnea if a patient has symptoms which you claim she does not so unless there is a good medical reason for her to be on CPAP then she is free to discontinue it and she doesn't need any other data or opinions to do so.

[quiescence at last]

just a snarky remark that should just be taken with a grain of salt is that she won't be needing a nurse to strap up a mask on her in her 90s if she dies before that from heart disease or stroke that generally does follow apnea around.

i have a relative that has apnea, and can't seem to make the jump into full use, partly because he thinks he'll die of his diagnosed cancers before the heart disease will get him (and he may be right).  I think not, since he already succombs to frequent afib and tachycardia.


Kidney disease and Apnea - NIH Article PMC4513269 says:

Recent studies suggest that sleep apnea induces CKD through increases in blood pressure, oxidative stress, and renal hypoxia. In other words, OSA may be an unconventional risk for CKD. There is clear evidence of an association between severity of OSA and extent of kidney damage.

QAL

[dataq1]

If she thinks using CPAP is BS ...

 I just want to be clear, she has never said anything like that.

She is looking to me (who is looking at this community) for reassurance that she has to either resign herself to being tied to a Cpap machine for the rest of her life or that she has to push her doctor to justify that treatment is actually medically necessary.  (That may be a tall order, as the doc has already filed the statement of medical necessity with her insurance)

As to flow limitations driving her pressure to 9-ish, that is indeed the case and have discussed that with her.  What is puzzling to us is that the so called flow limitation is not considered important enough to warrant an indexed value.

[kappa]

Late to this conversation, but when I look at the original sleep study I don't see necessarily faulty data. The patient could have paroxysmal atrial fibrillation which wouldn't necessarily be picked up by a cardiologist in a brief checkup, or even from a longer term (1-3 day) holter monitor study (if that's been done). Pulse rate isn't necessarily measured by counting - the inverse of the RR interval could be used, and RR intervals in AF are all over the place. Here's an example of paroxysmal AF from a Wellue SleepU pulseox:
   
As to whether CPAP is indicated... clearly the doc has made that call. The ODI seems to be fairly high (similar to AHI) and there's a strong correlation between O2 desatuation events and Hypopneas, which given that they are derived from different data sources would indicate that the pulseox data is valid.

[Geer1]

Ok she hasn't said that but that is how it came across because you/she are questioning both doctors, sleep study and the diagnosis. It has sounded like she wants any excuse not to use CPAP instead of evidence to support its continued use. The evidence to support continued use is in the original sleep data (like I mentioned before apnea, hypopnea, snore and flow limitation, literally every primary aspect of SDB) and sounds like it is in her OSCAR data as well. If she had good healthy breathing the pressure would be staying close to the min pressure and only momentarily fluctuating.

Ultimately it is her decision to treat SDB or not and the main thing I see is that she needs to understand why she is treating her SDB. I still don't get how she ended up being sent for a sleep study if she never thought sleep was an issue and as previously mentioned the recommended treatment for mild apnea cases (AHI < 15) is to only treat if a patient is symptomatic. It sounds like she isn't symptomatic so that means treatment likely isn't necessary. The only grey area is if the letter of medical necessity is targeted at treating the SDB to deal with other health issues, if it is just recommended to treat her sleep issues then it isn't what I would call a medical necessity (those letters look like they are pretty much just prescriptions/notes to insurance and could be significant like say a pacemaker or meaningless like say CPAP for a person with no symptoms). In short without CPAP she has to work harder to breath at night but if that isn't causing issues then it doesn't really matter.

Flow limitations are signs of SDB but single flow limitations are not usually an issue which is why they are a somewhat grey area. The issue is when groups of flow limitations cause excessive effort and/or high CO2 levels causing arousals (RERAs). These are often (not always) scored on PSGs but they aren't scored on home sleep studies because they don't have the EEG data to do so. Flow limitations and RERAs can have as much effect as more severe apnea can and there is an entire separate diagnosis (Upper Airway Resistance Syndrome) that covers patients with this issue. If your friend had symptoms but AHI was less than 5 she could have been diagnosed with UARS but because she also had obvious apnea and hypopnea and AHI > 5 her case is considered apnea. Since the majority of her events are hypopnea it does support that her issue is mostly a partial obstruction/restriction based SDB. Since RERAs are not scored (at least nowhere near accurately) by these CPAP machines it is also possible your friend hasn't seen any improvement in sleep or symptoms because she isn't yet adequately treated but we can't help determine any of that without OSCAR data.

I believe you already have all the information you need to help her make a decision (well at least if you can get some clarification from ordering doctor as to reasons she should be on CPAP).