New sleep study results

General Discussion on any topic relating to CPAP and/or Sleep Apnea.
Sanjay1976
Posts: 12
Joined: Fri Jun 10, 2022 6:43 pm

New sleep study results

Post by Sanjay1976 » Tue Jun 28, 2022 2:41 pm

I go to the Dr for sleep study because my heart doctor wanted to find out if I had sleep apnea.
Few weeks ago, my study was done with my mouth open (wife says so)
I called the sleep center and they said I should have been asked if I breath with my mouth at night.
They said that they would repeat (at no cost to me) and give me a strap and tape to keep the mouth closed.

I haven't seen the head Dr yet but the staff was allowed to give me the numbers today, and met with the dr in August.

Someone asked what the results of the studys were:
First Study (with mouth open
OAI 1.4
Hi 11.3
CAI 0.15
O2 93

Repeat (moth closed)
OAI 0.9
Hi 2.2
CAI 0.2
O2 94

my appointment with Dr is in August - so I'll see if I need treatment

Tec5
Posts: 173
Joined: Mon Mar 28, 2022 10:32 am

Re: New sleep study results

Post by Tec5 » Wed Jun 29, 2022 6:49 am

That is a really significant change in sleep study metrics in a matter of a few weeks, that appears to be attributed to mouth breathing.
IIRC, the reason for the repeat sleep study (both done before any Cpap treatment) was that you thought that some airflow was being missed because only nasal flow was measured in the original — is that correct?

Did anything else change between the two studies?

also, Sanjay you really should have appended this report to your thread that was started a couple of weeks ago. For anyone interested — that prior post is at: viewtopic.php?f=1&t=184526&p=1413984#p1413918
I am neither a physician nor a lawyer, so DO NOT rely on me for professional medical or legal advice.

User avatar
ChicagoGranny
Posts: 14409
Joined: Sun Jan 29, 2012 1:43 pm
Location: USA

Re: New sleep study results

Post by ChicagoGranny » Wed Jun 29, 2022 9:38 am

Tec5 wrote:
Wed Jun 29, 2022 6:49 am
That is a really significant change in sleep study metrics in a matter of a few weeks, that appears to be attributed to mouth breathing.
You can see the first study with the mouth open recorded more events than the second study with the mouth closed. This is to be expected because the mandible naturally moves slightly backward when the mouth opens. This backward movement tends to crimp the airway and impede airflow. (Although making assumptions about a mere two data points is fraught with the danger of being flat-out wrong.)

The ResMed ApneaLink Air device has a good record of identifying sleep-breathing issues whether the mouth is open or closed.

dataq1
Posts: 816
Joined: Sat Dec 24, 2005 8:09 am
Location: Northeast Ohio

Re: New sleep study results

Post by dataq1 » Wed Jun 29, 2022 9:52 am

ChicagoGranny wrote:
Wed Jun 29, 2022 9:38 am
making assumptions about a mere two data points is fraught with the danger of being flat-out wrong.
Agreed, but isn't that exactly the danger in reliance on a single data point, such as a one-night sleep study.
"THE INFORMATION PROVIDED ON CPAPTALK.COM IS NOT INTENDED NOR RECOMMENDED AS A SUBSTITUTE FOR PROFESSIONAL MEDICAL ADVICE."

User avatar
ChicagoGranny
Posts: 14409
Joined: Sun Jan 29, 2012 1:43 pm
Location: USA

Re: New sleep study results

Post by ChicagoGranny » Wed Jun 29, 2022 10:12 am

Sanjay1976 wrote:
Tue Jun 28, 2022 2:41 pm
give me a strap and tape to keep the mouth closed.
You now have a (limited) amount of data showing you breathe better with your mouth closed. And I have given you a description of the mechanism that matches this data. If you do some research, you will find that nose-breathing is overall healthier than mouth-breathing whether asleep or awake. Given these three points, are you doing anything to prevent mouth-breathing between now and your doctor's visit?

You might also want to adopt healthy side- or stomach-sleeping positions due to common greater breathing difficulty on the back.

Tec5
Posts: 173
Joined: Mon Mar 28, 2022 10:32 am

Re: New sleep study results

Post by Tec5 » Wed Jun 29, 2022 9:35 pm

ChicagoGranny wrote:
Wed Jun 29, 2022 9:38 am
You can see the first study with the mouth open recorded more events than the second study with the mouth closed. This is to be expected because the mandible naturally moves slightly backward when the mouth opens. This backward movement tends to crimp the airway and impede airflow.
I won't argue your point about mandible movement, because I just don't enough about it.
But intuitively, is does make sense that a mouth open would register more incidents of diminished air flow if the nasal cannula is not measuring the total inspiration airflow.
If the mouth is open consistantly throughout the sleep session (such that the measured nasal flow is, for example, 75% of the actual inspired flow ) I can imagine the variations in measured airflow would be minimized.
OTOH, if the mouth breathing is intermittent, the airflow measured at the nostrils will vary. Not necessarily because the total inspired flow has changed, but because the measured airflow is is missing the component of air that is passing through the oral access.
Hypopneas, by definition are periods of diminished airflow. If the total airflow is not being accurately measured (because of air escaping measurement during mouth breathing) AND the mouth breathing is intermittent, I could well imagine that the reported hypopnea events would be increased.
I suspect that that is what is going on with the OP, intermittent mouth breathing with a system that is only measuring nasal airflow, resulting in a higher HI (as compared with a measurement system that is only measuring nasal air movement.
That problem can be alleviated by either shuting down the alternate air pathway, or as Rubicon suggested using a oro-nasal cannula.

What is really significant is the OPs saturation level. IMO, there is no significant difference between 93 and 94 (1% is certainly within the margin-of-error). So I don't think we could suggest that Sanjay was any better oxygenated with his lips sealed. Admittedly, we don't know if the 93/94 values are average 02 or nadir O2.

What most stands out, is is a five fold change in hypopneas, with the only reported change being closing down that alternate airway (oral).
I am neither a physician nor a lawyer, so DO NOT rely on me for professional medical or legal advice.

Sanjay1976
Posts: 12
Joined: Fri Jun 10, 2022 6:43 pm

Re: New sleep study results

Post by Sanjay1976 » Wed Jun 29, 2022 9:58 pm

Hello everyone, answering a few questions,

@Tec5 I really sorry, I couldn't find the other topic. I apologize. Will I still be allowed to write here?

@ Grannie, I almost always have to sleep on my side because my wife and I have a small bed, so we cant really sleep on our backs much. Even though I am a small sized person, with both on our backs it is crowded.

@Tech5 Nothing has changed . I have no complaints about sleeping.

Thank you all very much,
Sanjay

User avatar
Pugsy
Posts: 63941
Joined: Thu May 14, 2009 9:31 am
Location: Missouri, USA

Re: New sleep study results

Post by Pugsy » Wed Jun 29, 2022 10:07 pm

Anytime you want to find one of your own posts it is easily done.

1. Click on your profile link
2. Look on the right side and click on "search user posts".....this will give you a list of all your posts and the topic(s).

I am okay with this new topic... it would be nice for everyone to read your history so here is a link to your another post.
viewtopic.php?f=1&t=184526&p=1413984#p1413984

And the first post that got derailed with all the nastiness which people can just ignore
viewtopic.php?f=1&t=184495&p=1413479#p1413479

Not that big of a deal you didn't stick to the other post. You aren't the first and you certainly won't be the last.

_________________
Machine: AirCurve™ 10 VAuto BiLevel Machine with HumidAir™ Heated Humidifier
Additional Comments: Mask Bleep Eclipse https://bleepsleep.com/the-eclipse/
I may have to RISE but I refuse to SHINE.

If you want to try the Eclipse mask and want a special promo code to get a little off the price...send me a private message.

User avatar
ChicagoGranny
Posts: 14409
Joined: Sun Jan 29, 2012 1:43 pm
Location: USA

Re: New sleep study results

Post by ChicagoGranny » Thu Jun 30, 2022 6:25 am

Tec5 wrote:
Wed Jun 29, 2022 9:35 pm
ChicagoGranny wrote:
Wed Jun 29, 2022 9:38 am
You can see the first study with the mouth open recorded more events than the second study with the mouth closed. This is to be expected because the mandible naturally moves slightly backward when the mouth opens. This backward movement tends to crimp the airway and impede airflow.
I won't argue your point about mandible movement, because I just don't enough about it.
But intuitively, is does make sense that a mouth open would register more incidents of diminished air flow if the nasal cannula is not measuring the total inspiration airflow.
If the mouth is open consistantly throughout the sleep session (such that the measured nasal flow is, for example, 75% of the actual inspired flow ) I can imagine the variations in measured airflow would be minimized.
OTOH, if the mouth breathing is intermittent, the airflow measured at the nostrils will vary. Not necessarily because the total inspired flow has changed, but because the measured airflow is is missing the component of air that is passing through the oral access.
Hypopneas, by definition are periods of diminished airflow. If the total airflow is not being accurately measured (because of air escaping measurement during mouth breathing) AND the mouth breathing is intermittent, I could well imagine that the reported hypopnea events would be increased.
I suspect that that is what is going on with the OP, intermittent mouth breathing with a system that is only measuring nasal airflow, resulting in a higher HI (as compared with a measurement system that is only measuring nasal air movement.
That problem can be alleviated by either shuting down the alternate air pathway, or as Rubicon suggested using a oro-nasal cannula.

What is really significant is the OPs saturation level. IMO, there is no significant difference between 93 and 94 (1% is certainly within the margin-of-error). So I don't think we could suggest that Sanjay was any better oxygenated with his lips sealed. Admittedly, we don't know if the 93/94 values are average 02 or nadir O2.

What most stands out, is is a five fold change in hypopneas, with the only reported change being closing down that alternate airway (oral).
All that being said, the most widely cited (349 citations) study of the ResMed ApneaLink published in a peer-review journal found,
... The results demonstrate a high sensitivity and specificity of the at-home ApneaLink AHI compared with the AHI from the simultaneous polysomnographic study at all AHI levels, with the best results at an AHI of ≥ 15 events per hour (sensitivity 91%, specificity 95%). The AHI comparison from the home and laboratory studies also demonstrates good sensitivity and specificity at AHI levels of ≥ 15 and ≥ 20 events per hour (sensitivity 76%, specificity 94%, for both).

Conclusions: Given the prevalence of sleep apnea in the adult population and in specific comorbid conditions, a screening tool may be useful in many diagnostic settings. This study demonstrates that the ApneaLink device provides reliable information, is a simple, easy-to-use device, and is highly sensitive and specific in calculating AHI, when compared with the AHI obtained from full polysomnography.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1978315/
I'll take the studied and tested opinion of experts before adding complexity for the patient.

Tec5
Posts: 173
Joined: Mon Mar 28, 2022 10:32 am

Re: New sleep study results

Post by Tec5 » Thu Jun 30, 2022 1:57 pm

Ahem, you do understand the difference between a screening tool and a diagnostic tool?
I would not dispute that the Type III is useful to screen, but an OSA diagnosis ought be based on diagnostic tests, not screening tests.
Additionally, I would be very interested if any of these studies you report specifically looked at detection of hypopneas with and with concurrent mouth breathing.
I certainly have not done a through examination, but I’ve yet to find any study that compares hypopnea measurement for nasal breathers versus dual airway breathers where only a nasal sensor is used.

That is all rather academic to the OPs situation, his provider apparently felt it was necessary to seal his oral airway to get a second (repeat) study.
I am neither a physician nor a lawyer, so DO NOT rely on me for professional medical or legal advice.

User avatar
ChicagoGranny
Posts: 14409
Joined: Sun Jan 29, 2012 1:43 pm
Location: USA

Re: New sleep study results

Post by ChicagoGranny » Thu Jun 30, 2022 3:02 pm

Tec5 wrote:
Thu Jun 30, 2022 1:57 pm
Ahem, you do understand the difference between a screening tool and a diagnostic tool?
Ahem, did you even read the part of the study I quoted?
ChicagoGranny wrote:
Thu Jun 30, 2022 6:25 am
Conclusions: Given the prevalence of sleep apnea in the adult population and in specific comorbid conditions, a screening tool may be useful in many diagnostic settings.
Don't just read the word "screening". Read the whole sentence carefully. Read that the researchers know there is a high prevalence of sleep apnea. HSTs are getting thousands of people properly diagnosed every year. This is being done using a small fraction of the resources needed for in-lab sleep studies.
Tec5 wrote:
Thu Jun 30, 2022 1:57 pm
his provider apparently felt it was necessary to seal his oral airway to get a second (repeat) study.
You don't know that. His doctor may have been simply mollifying a worried patient. His doctor may have been very careful that the patient does not take a complaint back to the cardiologist who referred him.

The ResMed ApneaLink is a very important tool in diagnosing sleep apnea without requiring huge resources.

Tec5
Posts: 173
Joined: Mon Mar 28, 2022 10:32 am

Re: New sleep study results

Post by Tec5 » Thu Jun 30, 2022 3:55 pm

ChicagoGranny wrote:
Thu Jun 30, 2022 3:02 pm
Ahem, did you even read the part of the study I quoted?
ChicagoGranny wrote:
Thu Jun 30, 2022 6:25 am
Conclusions: Given the prevalence of sleep apnea in the adult population and in specific comorbid conditions, a screening tool may be useful in many diagnostic settings.
Don't just read the word "screening". Read the whole sentence carefully. Read that the researchers know there is a high prevalence of sleep apnea. HSTs are getting thousands of people properly diagnosed every year. This is being done using a small fraction of the resources needed for in-lab sleep studies.
As a matter of fact I did read that very carefully. What I hear that statement saying is that there are many many people that may have sleep apnea. Medical practioners do not have the resources to provide PSG for all candidates that complain. So enter the screening tool, Type III and VI, that can be done at a small fraction of the resources time/money needed for a Type I or II.

Type I is still considered the gold-standard for diagnosis - is it not?

Other types III and IV are lesser standards - otherwise known as screening tools.
I am neither a physician nor a lawyer, so DO NOT rely on me for professional medical or legal advice.

User avatar
Rubicon
Posts: 1678
Joined: Sun Feb 20, 2022 6:59 am

Re: New sleep study results

Post by Rubicon » Thu Jun 30, 2022 4:58 pm

Well I tell ya, having administered hundreds (perhaps thousands) of ApneaLink studies, IMO for vanilla OSA I think it's VERY accurate. I especially loved the airflow signal, and the other channels were more than sufficient.

That said, once you get to train wreck sleep architecture (and you need to actually measure "sleep") then you need to drag out the expensive stuff.
Freeze this moment a little bit longer.
Make each sensation a little bit stronger.
Experience slips away.

Tec5
Posts: 173
Joined: Mon Mar 28, 2022 10:32 am

Re: New sleep study results

Post by Tec5 » Thu Jun 30, 2022 6:16 pm

Rubicon wrote:
Thu Jun 30, 2022 4:58 pm
Well I tell ya, having administered hundreds (perhaps thousands) of ApneaLink studies, IMO for vanilla OSA I think it's VERY accurate.
Glad to have the perspective of a experienced clinician.
The discussion on "accuracy" of Resmed ApneaLink is tangential to the information that Sanjay provided, and does not serve to illustrate the information he provided.
( I think I invoked your name earlier in this thread, to wit: a oro-nasal cannula could be used in lieu of straps/tape to capture oral airflow)

It looks to me that Sanjay's HI changed by a factor of five, and the only acknowledged change is that his oral airway was 'sealed'.

Can you offer any explanation for a change of that magnitude in HI?

I'm assuming that a factor of 5 ( 2.2 to 11) is well beyond the bounds of normal hypopnea measurement variation.
I am neither a physician nor a lawyer, so DO NOT rely on me for professional medical or legal advice.

User avatar
Rubicon
Posts: 1678
Joined: Sun Feb 20, 2022 6:59 am

Re: New sleep study results

Post by Rubicon » Fri Jul 01, 2022 3:39 am

Tec5 wrote:
Thu Jun 30, 2022 6:16 pm
Can you offer any explanation for a change of that magnitude in HI?

I'm assuming that a factor of 5 ( 2.2 to 11) is well beyond the bounds of normal hypopnea measurement variation.
These guys demonstrated a change in magnitude of 29:
The frequency of upper airway obstruction during sleep for all 12 subjects was profoundly influenced by the breathing route, being much greater during oral ventilation (apnoea-hypopnoea index 43±6) than nasal ventilation (apnoea-hypopnoea index 1.5±0.5, p<0.0001). Despite the fact that subjects had more REM sleep during the nasal breathing condition, the apnoea-hypopnoea index standardised for position (in the eight subjects who had position-comparable sleep periods in the two parts of the study) was still significantly greater in the oral breathing condition (supine position: nasal 3±2, oral 31±8; p=0.006 (fig. 4⇓); lateral position: nasal 2±1, oral 29±9; p=0.009 (fig. 5⇓)).
https://erj.ersjournals.com/content/22/5/827

so it's certainly within the realm of possibility that whatever the OP did was effective.
Freeze this moment a little bit longer.
Make each sensation a little bit stronger.
Experience slips away.