In Lab vs At Home sleep study.

[Yaatri]

This issue might have been covered before.  I apologise for raising it again if it has been discussed before. 

I have had 8 sleep studies between 2007 and 1017 2017, all of them were split studies done in a lab setting where you are monitored without any therapy for half the duration and the latter half is spent in titration in order to determine the appropriate pressure settings. I have not had a sleep study since 2017. 

The lowest AHI I have had without a PAP was 47 and the highest 90.8.   I have read of cases where patient, a long term PAP user showed a very low AHI in an at home study and was denied a prescription of CPAP?

My current insurance does a home a study.  How reliable is a home study? I don't want to be stuck with a crappy sleep study. 

Thank you all in advance.

[kappa]

Depends on the study. See this wiki page on different sleep test types. A Type II home test is pretty good IMO - you get to sleep in a familiar setting and they get similar data to an in-hospital test (EEG, EOG, ECG, etc - lots of wires & electrodes, chest/waist effort belts, etc). The Type III tests like watchpat collect way less data and type IV even less...

What are they hoping to find in this study that hasn't been determined previously?

[Crimson Nape]

I've heard, meaning I can't verify this, but stopping CPAP use 5 to 7 days in advance of the sleep study will eliminate any residual therapy benefit by the CPAP.

[hh9797]

Both in lab and at home have their own advantages and disadvantages. Obviously with the in lab one they general get a lot more data  because in addition to the equipment they can also observe as well, but with an in home sleep study you might get more accurate information as to what is closer to normal for you since obviously you are sleeping in your bed with your pillows in your normal sleep positions and so the data can be a little bit more accurate in that way. 

I know when I had my sleep study I had two separate ones, the first one was the most basic to see if I was eligible for a more detailed one because my complaint was with always getting headaches at a specific time of the day and didn't really mention being tired all the time because I was still dealing with Thyroid stuff and so didn't think twice about my fatigue since I had been fatigued since having my Thyroid removed to the point where it was just normal. 

Being in a lab they can get more information but being in your normal environment they can get more accurate information.  So it is quantity vs quality. Like if I don't have my normal pillows most the time the sleep is more like a rest then a sleep because I am awake and conscious a majority of the time because I can not get properly comfortable as such my data would be skewed in a lab to look better than it really is because of not being fully asleep. Much like how right now on nights I don't really sleep well my AHI on my CPAP is showing like 4-6, but on nights I do get a full nights sleep the AHI on my CPAP is showing 9-15 because on the nights I don't sleep well obviously my breathing isn't the same while semi conscious as a pose to fully asleep. 

So honestly while it may seem dumb the in home sleep test can be more useful data then an in lab one due to getting a better representation of your sleep.

[foss]

After moving to Texas, my local doctor ordered a home sleep study. It was some kind of Resmed device. My apnea scores without a cpap are very high.

I cannot sleep without a cpap. After suffering half the night, I removed the device and went back to my regular A10 Autosense and slept the rest of the night. The home study company out of Tampa was pretty ugly about it and wanted me to pay for the test. I called Medicare and they said just to send it back with a return receipt and not to send them any money.

I don't know what I will do when my A10 wears out. I may just have to buy one out of my own pocket. One of the companies listed in this forum's database has a copy of my prescription so buying it will not be a problem.

foss

[dataq1]

@hh9797: 
You corrected yourself later, but the statement;
"Being in a lab they can get more information but being in your normal environment they can get more accurate information." is somewhat misleading. Your normal environment may lead to better representative results but has nothing to do with more accurate.

That said, an even better representation of sleep dysfunction would be a HSAT (home study) conducted over several days. (I know that I don't have the same quality sleep day-after-day).

Aside from that, my principle concern about HSATs is whether, in their current configuration such as Resmed Apnea Air Link, all of the air flows are accounted. IMO, persons who mouth breathe on occasion ought be fitted with lip seals or a oro-nasal cannula (to measure both airways).

Are there any academic/medical studies that examine the impact of incomplete air-flow measurement for those with mild/moderate OSA, perhaps specifically hypopneas? 

[hh9797]

@hh9797: 
You corrected yourself later, but the statement;
"Being in a lab they can get more information but being in your normal environment they can get more accurate information." is somewhat misleading. Your normal environment may lead to better representative results but has nothing to do with more accurate.

While out of three times making a similar statement the second time I did make the statement shorter, but right at the very beginning the statement was "but with an in home sleep study you might get more accurate information as to what is closer to normal for you since obviously (blah blah blah about your sleeping environment)" clarifying "as to what is closer to normal for you thus defining what I meant by accurate right off the start as to based upon your normal environment. Yes the second time I made the same statement I left off the defining point about "what is normal to you" and so could be construed as misleading if you didn't pick up what I had said the first time about the environment, and then the third time to summarize I worded it entirely differently. 

So while yes if you take the single sentence out of context then yes I could see how it could be misinterpreted, but I assumed having defined "more accurate as to what is normal to you due to the environmental differences" in the first paragraph I didn't need to redefine that exact same constraint in the second paragraph because it had already been defined. But I guess it would also be fair to assume that maybe not everyone on here necessarily has English as their first language and so yes I probably should have picked a better wording, like the phrasing you used. Because while "accurate" was defined in relationship to environment right in the very first paragraph I can see how that could be missed or misunderstood if reading quickly. So fair point, I will try to pick my wording more carefully as a pose to defining what I mean by a word and then not redefining it every time I use it, I will take that into consideration in the future.

[dataq1]

@ hh9797. 
I believe that we are both on the same page, what is desired is a sleep study that most accurately represents a client's normal sleep experience. Not only would we want measurements made during a normal sleep experience (your overall point) but we would want those measurements be made with accuracy (my point about misreading airflows). 
I hope you don't think I was criticizing you, not my intent. But very often the public has a confused notion about  accuracy . (ie, we accurately counted the votes, but we only counted the votes from one county ---- accurate but not representative of the state).

Yaatri, the OP, asked the question how reliable is a home study.  The key word is reliable - what a person means when they say "reliable".  In one context, I would suggest that reliability is measured by repeatablity.  ( the same test repeated multiple times gives answer).

Although Yaatri implies that he has has multiple lab-based tests over the years, the measured result 40.7 and 90, are very different - hence one could say the test was not 'reliable'. OTOH, the diagnosis apparently was the same - significant OSA - so viewed in that contest the test was reliable.

But, Yaatri is asking about reliability of home-based sleep studies (usually classed as Type III and Type IV sleep studies). If he means reliable in terms of consistently getting the same "answer" (AHI is X +/- y) on repeated testings, the likely answer is no.  IF he means reliable in terms consistancy of diagnosis and recommended treatment, then that answer is likely varies according to the class of OSA degree.

(I have searched for academic/medical papers for HSAT consistancy (measured AHI) over multiple patients that have had HSATs multiple times in close succession, but have not found any yet -- I'd appreciate any leads.

[hh9797]

Ah no, I got what what you meant, my point was simply that while yes I should have chosen words that are, for a lack of better words harder to misunderstand or mistranslate seeing as I had defined what I meant in the first paragraph and assumed that the one definition didn't need repeating but that could lead to confusion. I was not offended by your comment at all, it was a good point to make because it is always best to just chose the right word in the first place as a pose to having to redefine a word because it reduces the chance of being misunderstood.

I didn't read it as an attack or anything I read it basically "Hey you used this wording which could be misread like this, maybe this wording instead would be better" to which I agreed the wording you picked was probably less confusing because I didn't think about how it could be misread until you pointed it out. The thank you for pointing that out was not being sassy, it was genuine.

[hh9797]

But, Yaatri is asking about reliability of home-based sleep studies (usually classed as Type III and Type IV sleep studies).

If he means reliable in terms of consistently getting the same "answer" (AHI is X +/- y) on repeated testings, the likely answer is no. 

IF he means reliable in terms consistancy of diagnosis and recommended treatment, then that answer is likely varies according to the class of OSA degree.

The hard part with saying yes or no to the first meaning of X +/-Y is it is extremely hard to tell because the variables used to generate X and Y are almost never the same and so while they can vary wildly based on the variables of that specific night and so would be no, but if you are looking deeper and are looking for X +/- Y with controlled variables then the answer would be yes. Now obviously the issue is that while X could be a constant of your average AHI, Y would change based upon the variables like how tired you are, how much energy you have to burn, the temperature, the humidity, are you sick or not, wither or not your mussels are sore from work, wither you rolled left or right first thus changing the rest of the positions you are a sleep the entire rest the night etc. If you have variables A,B,C,D,...,Q,R,S are all the exact same then X and Y would be the exact same as well BUT it is impossible to keep all those variables the exact same and as such you are correct is saying no. So while you are correct in saying no to that part it is a bit misleading because it makes it sound like the test itself is at fault, but that would be true of both at home and in lab tests and are not exclusive to one or the other and as such while that answer is correct, with his concern being about in home vs in lab you really should define the fact that that is true regardless of location.

To the second part, that is 100% fair because if one night you are say 8 and the next night you are say 15 and the next night you are say 4.5 depending on the doctor one could interpret that as you are in the normal range but just had two wacky nights, another could conclude that you are mild and you had one really good night and one really bad night, and another could conclude that you a moderate and you just had skewed data on the two lower ones due to not being able to sleep and so the test shows one number but doesn't exclude the time that you are more or less resting and not sleeping which is part of why the number can be misleading to someone who doesn't look at the data all day everyday because they can go "yeah this number seems right, they were in a good sleep all night" or go "yeah the computer is saying x but it is probably a fair bit higher then x because I can tell from the data that 1.5 of the 6 hours the person was merely resting which can artificially lower the numbers because a bit". If you are at 40, one night, 70 another night, and 46 another night then it doesn't really matter that the gap is much larger because all three are consider sever regardless of the quality of the sleep to get the data.  

Reason I say that the number is only part of what is important and having someone trained to look at the data is a lot more valuable is because like lets take my last nights data for example, if you look at it as a whole and treat it as someone who is not trained to look at the data then you would see an AHI of 10.47, but for someone who is trained to look at the data they may go "Well I can see that going to sleep and waking up when you are mentally awake you are fighting the pressure causing an increase of obstructive events because you are not adjusted to the pressure yet, if we lop off the first 20 minutes and last 5 minutes of data then your true AHI for when you were sleeping was actually 6.18 and not 10.47, still a bit high but not to the degree that it first appears if we ignore the data of when you are actively fighting the pressure".

So in short for your first part you are correct but that can be a bit misleading because that is true of any test regardless of if it is a home or in lab test. And your second part is spot on, it really comes down to how the person looking at your data interprets it because it is not always black and white, sure the numbers give a rough ball park to what it probably is but it requires a deeper dive then what any machine can truly do.