Mythbusting: Are Smartwatches and Rings Accurate for detecting AFib and monitoring Sleep?

Are you putting too much trust in your health and fitness tech? In this 5-Minute Check In, we ask: Can your smartwatch really detect AFib and is your ring accurately monitoring sleep? We're diving deep into the scientific data to reveal what these devices actually promise vs. what they actually deliver. Get the insights in just a few minutes.

Guests: Dr. Thomas McGinn, SEVP and Chief Physician Executive Officer; Dr. Ankita Sagar, System VP Clinical Transformation and Well-Being; Dr. Phil Chang, Chief Medical and Quality Officer; and Brooke Burgess, System Director Clinical Communications

Studies: https://www.jacc.org/doi/10.1016/j.jacadv.2025.102133

https://pubmed.ncbi.nlm.nih.gov/41230431/ 

Transcript

SPEAKER_02 0:06

Hi, and welcome to another episode of Mythbusters. Well, we have two very interesting myths to discuss today. And to help us discuss this and set the stage, I have three amazing guests. Backed by popular demand is Brooke Burgess, who heads up clinical communications for Common Spirit Health. Brooke, thank you for being here.

SPEAKER_00 0:26

Thank you for having me.

SPEAKER_02 0:27

And like always, we have Dr. Ankara Sagar, our VP for clinical transformation. Dr. Sagar, thank you for joining us.

SPEAKER_03 0:35

Hey, it's great to be here.

SPEAKER_02 0:37

And I think this is your first time. Dr. Philip Chang, our new Chief Medical Quality Officer for Comet Spirit Health, is joining us. Phil, thank you for joining us.

SPEAKER_01 0:47

Yes, thank you. Excited to be here.

SPEAKER_02 0:49

We're going to talk about two things today. Uh, one is the two wearables, the ring and the watch that do a lot of data collection. And so, Brooke, tell us a little bit about how we ended up wanting to talk about this. What's going on out there? I have a watch. I think you got a couple of things, if I'm not mistaken.

SPEAKER_00 1:06

I take your watch and raise you a ring. I've got two. Um, and I'm so excited about this.

SPEAKER_02 1:11

By the way, Phil wins. Phil's got all three. He's got three things, by the way. So, yeah. Okay.

SPEAKER_00 1:16

This is an exciting talk. I'm excited about it. Uh, you know, wearables are really popular right now. Many people have a ring, a smartwatch, what have you. And I think I speak for many people when I say we just want to know: are these devices accurate? Are they reliable? Or at the end of the day, just causing more anxiety? And so I'm curious to hear what this group thinks.

SPEAKER_02 1:36

Those are excellent questions, a lot of questions. But let's focus on one. Okay. And I'm going to turn the first one over for the watch to Akara. And in this very specific question, this is because it's hard to get the data on these things. Can the watch detect an arrhythmia, an irregular heart rate called AFib on its watch? From distinguishing it from normal science, but so what is the data on that? So that might be, we're going to anchor on that one question for the watch, but take it away.

SPEAKER_03 2:06

Okay. So this has been a question long in the making since I think the first watch came out. So 2025 great meta-analysis published that looked at the accuracy of smartwatches in specifically detecting age of fibrillation in patients who did not have a history of AFib.

SPEAKER_02 2:26

So just normal, normal good old folks who's walking around gonna pick up AFib. Yep.

SPEAKER_03 2:31

Exactly.

SPEAKER_02 2:31

Okay.

SPEAKER_03 2:32

Okay. So in the meta-analysis, 26 studies, so almost 17,500 patients just a lot of watches. A lot of watches. And it wasn't just a US-based population, which I like, because then you can really generalize it at larger scale because of multiple nations. Bottom line, sensitivity of 95%, meaning it can detect a lot. And then when we think about specificity, can it specifically look at a detect a fib? 97% specificity.

SPEAKER_02 3:07

Good numbers.

SPEAKER_03 3:08

Good numbers, but I'm gonna give you a new number we haven't talked about these series before, which is the pooled area under the curve on the AUC.

SPEAKER_02 3:18

Very nice.

SPEAKER_03 3:20

Um the pooled AUC basically is a grades test to determine whether the test that we are looking at currently is accurate in differentiating between normal and abnormal. Abnormal being AFib.

SPEAKER_02 3:36

AFib. Yep. And how did it do?

SPEAKER_03 3:40

So 0.5 is the lowest score, one is the highest, meaning 100% accuracy. The smartwatches came almost one per to a full one. It was 0.98. So 98% A plus plus.

SPEAKER_02 3:56

A plus bottom line is good at detecting AFib. Okay.

SPEAKER_03 4:01

I think it's better than a physician, maybe even in detecting AFIB.

SPEAKER_02 4:04

All right, well, let's all right. Let's take it easy. Okay, come on. Maybe easy go here. Maybe all right. Well, let's turn to the second question. All right. Um, Dr. Chang, your question is on the rings that people are wearing these days, giving a lot of information about sleep. The question is, is that data accurate compared to, say, like a regular sleep study? Is it giving you accurate information, things you can actually depend upon, or is it you know all over the place? What what what did you find when you looked at the literature and as aware of the ring?

SPEAKER_01 4:39

Yeah, so so I think I think zero in on sleep is it's great because the ring, many of these rings have lots of functions, and the this the data coming out from around the measurement of sleep is is quite rich. So similarly, I I uh I'm gonna zero in on my meta-analysis that was published in 2025 from Auto Open, which is an auto-angology article. Um, published lead also, Dr. Khan from Sydney Buffalo, six studies in this meta-analysis from 2020 to 2024, almost 400 patients. But this is a little bit different from AFib, which is sort of all or none. In sleep studies, what they're able to do is to compare medical sleep lab parameters. So these are parameters such as um uh total sleep time, uh late light sleep time, deep sleep time, onset of sleep, etc. So in these different measurements, is the ring, and this article specifically talks about a popular ring called aura ring, is the ring in these measures comparable to a professional sleep app like a PSG polysonography or a tigraphy, ACT? And the answer is there's no statistical significance in each one of these measures. So validating that the measurement, each measurement is accurate uh or accurate enough. Um that's not to say it doesn't say as opposed to AFib, Bill, you've got sleep apnea. It doesn't do that.

SPEAKER_02 6:12

Right, it's it's just telling your oxygen is low, your sleep is hesitant, you know, late to start. Okay. So 100%. So we can say it's accurate, but we're not we're it's not diagnostic. So what do we do with that data then? So what do we recommend a patient does? It lets I mean if you know, if you're concerned, I suppose we should just send the data somehow to your physician, I guess. Because you you you're not gonna make the diagnosis yourself.

SPEAKER_01 6:40

Right. Right. I I would imagine, you know, look, I'm not a sleep expert uh physician, I'm a trauma surgeon. I would imagine that if if I'm bothered by my sleep and I'm an educated person who can Google research, um, I might take a look at my numbers and go, okay, I don't have any significant drop in my oxygen saturation that's causing my sleep quality to go down. Maybe I shouldn't be as concerned. Or I'm concerned, let me bring my phone to my physician and have my physician take a look at these parameters. And and the good thing is I have weeks, if not months, of data. Well, that's good for you.

SPEAKER_02 7:20

It's not so good for the doctor who's got to read all that, but yeah. So so we have so we have two situations. I think one is more of a diagnostic thing where this watch can diagnose AFib. The other one is more it's like a lot of data, pretty valid, unclear what you're gonna do with all that sometimes. So, but now, Brooke, people use these things for other reasons, they don't really walk around thinking, I wonder if I have AFib or I wonder if I have sleep apnea. And I guess, you know, you asked the question at the very beginning: is it good for people to have these things? That's a different question about whether they're accurate. So I, you know, what you wear them. Do you think they're good for your day-to-day life?

SPEAKER_00 7:56

Or you know, I think it gives me some information that's useful. Um, and for me, I think what I'm hearing this group say is if you've got some data, if you've got some concerns, uh reach out to your physician, reach out to your primary care doctor, uh, get an appointment, um, and and and ask your questions. Um, but you know, data can't isn't a bad thing. So if we look at these myths, are we saying they're busted? Are we saying number one, is a myth that watches can accurately detect AFib? True or false?

SPEAKER_02 8:26

I think they can. So it is not a myth. They can actually detect a fib.

SPEAKER_00 8:33

And then rings give accurate information about sleep?

SPEAKER_02 8:36

I think that's true. So it's not a myth. So we have two truths, and they're not myths. So that's very exciting for us. Um normally we're busting and and yeah, they're all myths. So, two things, two wearables. Data seems to be accurate. I I'm gonna end this by saying though, I don't know if they are good for you in other cases, you know. So, I mean, we did talk a little bit about sleep anxiety and this potentially causing people to get too anxious because of all the data they're getting that they're not sleeping. So, um, you know, you they can be an extension of your sleep hygiene and help you think about am I really doing things the correct way? But they may also make you so anxious that you can't get to sleep. So that you know, that that story is not yet figured out. So all right. Well, thank you, the three of you, for talking about these two wearables. And I really enjoyed the conversation. And I am not gonna get a ring. Sorry, I'm not gonna do it. So I can't do it. But Christmas present. Christmas present, yeah.

SPEAKER_03 9:41

Don't I don't have either. So Tom, what do you have over there?

SPEAKER_02 9:44

I'll cut it what are you exactly?

SPEAKER_03 9:46

I have like an old school watch, everybody, like you know, the one that you wear and then you wind it.

SPEAKER_02 9:52

You wind it. All right, I'm with you. I think I if I didn't have somebody gave me this watch, I wouldn't wear it otherwise. But well, thank you everybody for joining me in this episode of Mythbusters, and we'll see you at the next episode.