Smart watches and sleep apnea ?

[RobbyM684]

Another thing that crazy about these watches......
Last night I was asleep (as far as I was "aware" I was unconscious)...for 6 hours and 22 minutes,
But my watch tells me that I was AWAKE for a total of 50 minutes in 22 episodes.

Since we know that "awake time" is not reliable for apnea event detection,
That suggests that about 15% of my breath record is not reliable?

Do you suppose that there is too much reliance on inference and extrapolation?

[lazarus]

I personally would consider ALL watch info about the human body, awake or asleep, to be unreliable info in every way, other than perhaps as providing possible hints for very broad trending impressions over very long periods of time.

On the other hand, I consider use of overnight fingertip recording oximeters to be somewhat useful for occasional use by an OSA sufferer on PAP (despite movement artifact issues). And I consider AHI info from a CPAP machine to be very, very valuable (although imperfect in comparison to PSG)--in fact the most valuable available info of all for tweaking treatment parameters and comfort settings.

The rings fall somewhere in the middle to me, but much closer to the unreliable watches than to a good recording fingertip pulse-ox.

Hey, just me.

And I'm often wrong.

Just not as wrong as the Tweedle Bros.

[I'm not a Robot]

My sleep specialist told me not to believe ANY of the sleep data on the smart watch.

It is good for counting steps....most of the time. It can be fooled if I wave my arm around frantically.

It does tell the correct time.

[dataq1]

My sleep specialist told me not to believe ANY of the sleep data on the smart watch.

It is good for counting steps....most of the time. It can be fooled if I wave my arm around frantically.

It does tell the correct time.

Try wearing it while drumming in a rock band. 10K steps easy in one set.

[lazarus]

if I wave my arm around frantically.

I know you say you aren't a robot. But, by any chance, do you happen to shout anything like "Warning, danger, Will Robinson!" when you do that?

https://youtu.be/zePYlaVVo_M

Asking for a friend.

[I'm not a Robot]

if I wave my arm around frantically.

I know you say you aren't a robot. But, by any chance, do you happen to shout anything like "Warning, danger, Will Robinson!" when you do that?

https://youtu.be/zePYlaVVo_M

Asking for a friend.

My cat's name is Will and the family just purchased an "exciting new cat dryer feature" for the microwave.

[babydinosnoreless]

if I wave my arm around frantically.

I know you say you aren't a robot. But, by any chance, do you happen to shout anything like "Warning, danger, Will Robinson!" when you do that?

https://youtu.be/zePYlaVVo_M

Asking for a friend.

My cat's name is Will and the family just purchased an "exciting new cat dryer feature" for the microwave.

[chunkyfrog]

Long ago, I had the good fortune to have a step counter that was very waterproof.
And the bad luck to leave it in my pocket, where it was washed.
Yes, it was fooled--a lot!
It had over a week's worth of steps that afternoon.

[Janknitz]

Long ago, I had the good fortune to have a step counter that was very waterproof.
And the bad luck to leave it in my pocket, where it was washed.
Yes, it was fooled--a lot!
It had over a week's worth of steps that afternoon.

The step counter on my Apple Watch gives me credit for knitting. When my husband's FitBit is close to a round number (he regularly gets between 16,000 and 20,000 steps a day without cheating!) he gives a dog a belly rub to round up his numbers.

I do look at mileage for goals and comparisons, and exercise minutes, but I don't trust the number of steps. The altitude thing isn't accurate either. I live on the top of a hill. Somehow the distance I go downhill is less than the distance I go uphill on my walks. Even when I reverse my route. Hmmm . . .

Lots of Apple Fan Boys swear by the accuracy of their Apple Watches. They don't like to hear it isn't so.

[lazarus]

Lots of Apple Fan Boys swear by the accuracy of their Apple Watches. They don't like to hear it isn't so.

According to some I know who work there, Apple and its customers can be more of a cult-community than a company.

May Lord Cook and his disciples bless and protect us all.

But in defense of the fan boys, many of us naturally take more (and thus, shorter) strides going uphill. But it is claimed that it all eventually evens out over time based on your average on level ground.

Although I find sorting all that out can often be an uphill battle.

[dataq1]

Y'all are conveniently ignoring an actual scientific review of published studies
https://www.ncbi.nlm.nih.gov/pmc/articl ... s%200.993.

But why let established controlled studies get in the way of bias?

[Janknitz]

Y'all are conveniently ignoring an actual scientific review of published studies
https://www.ncbi.nlm.nih.gov/pmc/articl ... s%200.993.

But why let established controlled studies get in the way of bias?

I guess my Apple Watch didn't read the review article or the studies it's based on. Personal experience does not correlate.

The article indicates that the readings in each study were initiated (to initiate an O2 sat reading you have to open the Blood Oxygen app and sit still with your wrist in a particular position for 15 seconds while it takes the reading--it will tell you if you are moving too much or it can't measure during the initiated reading because of wrist position, tightness or looseness of the wristband, and who knows what else. Even when the watch measures for the full 15 seconds, the readings often fail. The watch also takes reading at random intervals without initiation. I'm seeing the difference in the random, uninitiated readings my AW makes. I don't know if there are other random readings that fail, because the watch does not report those.

I have heard of first responders on a plane using an AW to monitor someone experiencing a cardiac event during flight, and probably in that situation, with initiated readings, it can give a reasonable indication of whether O2 sat is good or not. Whether it's accurate to the degree cited in the studies under very controlled conditions is unknown.

But, in my experience the random readings are not always accurate by a long shot. For example, my AW 6 (the same model used in the studies cited) recorded O2 sats down to 84% during sleep (using CPAP on my usual settings). The recording pulse oximeter had me well into the 90's, no desats. One of the really low random readings this past week (85%)was at about 6 PM, when I was wide awake, probably reading at the time, not in any respiratory distress, heart rate was my usual resting heart rate around 60. It doesn't flag me, so I didn't check with the finger pulse oximeter (only saw that reading today, when I was responding here), but when I have been at 85% O2 sat for real due to illness or altitude I have definitely felt awful--that was not the case here. Note that you cannot use the AW to do things like monitor during activity, because if you aren't holding still it will fail. When I'm sick with bronchitis or pneumonia, my resting O2 sat is usually marginal but drops significantly during activity. The watch can't tell me that, the finger pulse oximeter does.

My personal experience is that the random readings sometimes vary by a lot, and--unlike the studies cited--the readings tend to be lower than the pulse oximeter readings.

Where the AW could be particularly helpful for our population is during the night to see if we are getting good oxygen perfusion while using CPAP. Any reading during sleep would be random, not initiated under clinical conditions. My experience says that it's not useful in that context at all. It is NOT a medical device.

But don't let my real life get in the way of your studies.

[lynninnj]

Another thing that crazy about these watches......
Last night I was asleep (as far as I was "aware" I was unconscious)...for 6 hours and 22 minutes,
But my watch tells me that I was AWAKE for a total of 50 minutes in 22 episodes.

Since we know that "awake time" is not reliable for apnea event detection,
That suggests that about 15% of my breath record is not reliable?

Do you suppose that there is too much reliance on inference and extrapolation?

Multiply your AHI by hours you were “asleep” and compare.

I often wake up when I have an apnea that becomes prolonged.

[VVV]

Does anyone use these smart watches for the blood oxygen and ecg and are they worth the cost ?

My answer is to different questions than what you are asking. First, I won't bore you with any detail about how I ended up with an Apple Watch that I never wanted. But, I did, and I reluctantly started using it.

1. The sleep data has been great as an aid for me to improve my sleep hygiene and see the results reported in the watch. When it reports my total sleep was 7 hours with one hour each of REM and Deep, I feel great the next day. When the total sleep drops to 6 hours and REM and Deep are less than one hour each, I get really fatigued in the late afternoon of the next day.

2. I also look at my sleeping heart rate. If it has a couple of periods of 60 - 63 BPM, I know my sleep was good, and I will be energetic during the day.

3. It's also been reassuring to see that I am falling back to sleep after awakenings more quickly than I realized. Maybe the watch shows it took me from 3:00 a.m. to 3:20 a.m. to fall asleep again. Lying awake for those 20 minutes always felt like an hour. Worrying about this tended to stress me. Now, I can look in the morning and see I wasn't awake as long as it seemed. This is refreshingly reassuring about how I will feel during the day.

4. Exercise and heart rate. I now strictly use the optimal heart rate zones that Apple recommends. I have always been aggressive about training, and I know my exercise was at heart rates that were too high for my age. My trainer has shown me how better results can be achieved by using the lower rates that Apple recommends for me. I not only use these zones for aerobic training but also for weight lifting. At the end of each lift, I check that my heart rate did not go into the orange zone. If it did, I lower the number of reps by two on the next lift.

5. As a side benefit, my sleep is better since I started limiting my heart rate during exercise. My trainer said this was to be expected.

6. Oxygen levels. On some long, tiring days before dinner, I will take a 15-minute timed nap sans CPAP. If I awaken feeling like I had apneas, I can look at the watch and it will show a desat to 89%. If I awaken feeling refreshed, the ox runs from 95 to 99%. (If you are really concerned about overnight oxygen levels, get a recording pulse-oximeter that is compatible with OSCAR.)

7. ECG. My heart is healthy, so I am not a good judge of this function. I did print out a couple of ECGs to show to my PCP at an annual visit. I told him there was a concern that my ECG graph was not perfect. He said everyone's heartbeat has some irregularities and mine were of no concern. (He was impressed with the quality of the report.)

8. I had a 42-day bout of long COVID in 2021 and a 70-day bout in 2022. I tracked my sleeping and resting heart rates during these periods. It was clear that my heart rate was running 10 to 12 BPM higher than when I was healthy. More recently, I had a short, but violent norovirus infection. For a few days, my rate was again up 10 beats. When the virus cleared, I was weakened. I used the heart rate function to tread easily back into the gym. Without the Apple Watch, I would have gone back in too hard and too soon.

That may not have answered your questions, but I am so excited about the results my Apple Watch has helped me achieve, I wanted to express this.

[VVV]

But, in my experience the random readings are not always accurate by a long shot. For example, my AW 6 (the same model used in the studies cited) recorded O2 sats down to 84% during sleep (using CPAP on my usual settings). The recording pulse oximeter had me well into the 90's, no desats.

Both recording pulse-oximeters that I have owned frequently reported alarming artifacts (desats) that I feel were not accurate. I believe this is even true of the monitors used in hospitals.