Looking for assistance interpreting SPO2 data

Hi everyone,

I've been curious about the possibility of having some degree of sleep apnea. I can provide some background/health info if requested. I did some research into pulse oximeters and found a good deal on the CMS-50F and recorded with it for the first time last night. I know there's no substitute for a real diagnosis from a doctor and a proper sleep study, and my intent isn't to conclude I have sleep apnea and treat myself without ever getting a diagnosis. In the event that the data seems to indicate that sleep apnea is plausible, I will seek a proper diagnosis.

I'm brand new to this and I was hoping someone could look over my data and weigh in with their opinion. Unfortunately I didn't sleep too well last night (a fair bit of tossing and turning and quite a few forceful coughing fits since I've got a lingering dry cough from being ill a few weeks ago -- I'm assuming those are the cause of pulse rate spikes and elevations), so I know the data isn't great since I didn't spend the whole night actually sleeping. I plan on recording a few more nights of data at the very least.

With the default SleepyHead settings (flag SpO2 desaturations of 3%+ for 8 seconds or more), there are 92 Sp02 Drop events throughout the recording, making for an 11.57 AHI which appears to be moderate sleep apnea.

However, I've read elsewhere of a criteria of 4%+ desaturations for 10 seconds or more, and there were 11 of those events, making for a 1.38 AHI.

I've also read that drops of 4%+ of the awake + resting baseline are significant (and that baseline for me appears to be 98% based on my initial observations wearing the CMS-50F for a few minutes at a time while awake), but SleepyHead doesn't appear to be 'honoring' my attempt to change the "Flag SPO2 Desaturations Below" to 94% (nothing changes when I click Automatic Oximetry Cleanup, and when I return to the Preferences menu that option has reverted back to 88% -- a glitch maybe?). It looks like there would be a very large number of events if that were the criteria.

The lowest saturation level throughout the night was 88% for 7 seconds immediately followed by 87% for 4 seconds. That was the only time I hit 88% or lower.

Below are the graphs:



Again, I'm not seeking a diagnosis over the internet of course, but since I'm a little confused by the multiple criteria I've read about for determining the AHI, I was hoping someone could look over this and weigh in. Just vague thoughts like "everything looks fairly normal, probably not an issue unless you want to see a doctor to rule it out" or "the data is concerning, I recommend you get a proper sleep study" are totally fine and appreciated!

You can't determine AHI from sp02 readings. Your levels don't look horrible. I would suggest recording for a few nights in a row and let us know which nights you felt like you slept best.

A sleep study is only way to know for sure but why do you think you have sleep apnea?

jeffyj432 wrote: . . . In the event that the data seems to indicate that sleep apnea is plausible, I will seek a proper diagnosis. . . .

In my opinion, that thinking reflects a flawed premise. The fact is that sleep apnea is plausible regardless of the data you are collecting.

Although it is true that data from home SpO2 does fairly well indicating whether someone has severe untreated OSA, it cannot in any way whatsoever indicate that OSA is unlikely for a person, since it too often misses those with so-called moderate-to-mild OSA, which can easily wreck sleep and health very significantly. In other words, your test can indicate a positive likelihood finding for severe OSA, but it is incapable of providing a conclusive negative finding for the likelihood for OSA itself. Many people with serious sleep disturbances from breathing issues never desaturate in a way that a home pulse-ox will register clearly.

OSA cannot be simplified down to a mere breathing/saturation issue. It is a serious sleep disorder. A pulse-ox tells you zilch about quality of sleep and how breathing is affecting it. A person who desaturates may have OSA. But a person who does not desaturate in a sustained way may have OSA too.

Although most pulse oximeters have a sensitivity of 100% and specificity of 95% in people with 25 or more desaturation events per hour, this drops to 60% sensitivity and 80% specificity in people with five to 15 desaturation events/hour. Additionally, not all pulse oximeters are equivalent in their ability to detect the 4% desaturations necessary to detect hypopneas. -- http://www.rtmagazine.com/2009/06/the-r ... p-studies/

I didn't say what was quoted.

USMCVet wrote: ↑

Mon Mar 05, 2018 12:47 pm

I didn't say what was quoted.

Sorry about that. Not sure how that happened. I fixed it. By hand.

And I liked your answer better than my wordier way of saying the same thing, anyway.

I'd be quite happy with those results and get on with my life. There is nothing significant to treat. You can do a sleep study if you want to, you may still be arousing from sleep
This is what sleep apnea with o2 desaturation looks like

https://imgur.com/a/FrT8O