Interview with Dr. Cathy Goldstein

We sat down to talk with Dr. Goldstein on what she sees as the future of wearables in the sleep clinic. Enjoy!

Thank you for taking the time to meet with me today! Could you take a minute to introduce yourself and say a little about what your job is?

Cathy Goldstein, MD. I’m a neurologist, Associate Professor of Neurology here at Michigan Medicine, and my clinical practice is entirely in sleep medicine.

You’ve done work with [Arcascope CEO] Olivia on wearables, and you’re heavily involved in the AASM and consumer sleep technologies. Where do things stand today for consumer sleep technology and wearables, and where do they need to go?

These devices really started becoming prominent about 8 years ago. I remember I was right out of my fellowship at that time, and I thought, wow, these will be so awesome for when a patient sees me in the clinic: I have all these questions about their sleep and sleep timing, and how they sleep on the weekdays vs weekends vs vacation, and they’re in the position of having to try and remember what their problems have been over the long time they’ve been waiting to see me.

And the problem with a sleep log [that someone fills out manually] is that it’s hard to keep up with every day. In this busy world, you need more of a passive degree of tracking, particularly over time. So when wearables came out I was like, wow, you know, wouldn’t it be cool if when the patient shows up I can just take a look at their data in the last six months and see their sleep patterns.

The problem as far as adoption has gone, is that we don’t know how accurate they are at tracking sleep. So, there’s a medical grade version of consumer trackers called “actigraphy”, although they’re not completely accurate, we KNOW how accurate they are. And so, particularly in science and medicine, what is known is better and less scary—even if the performance isn’t great— than the unknown.

There are a lot of unknowns in regard to consumer-targeted sleep tracking because there’s not a lot of peer-reviewed literature about the performance of these. It’s growing, but even when the accuracy does get reported in a paper, oftentimes the algorithms change with updates, or the hardware changes a little bit with each iteration. The big thing is—we just don’t know. And that’s really prevented adoption in research and clinical practice, unfortunately.

What are the biggest misconceptions about sleep wearables that you see out in the world?

The biggest misconception is that they’re totally inaccurate, that they’re inferior to actigraphy for some reason, because the data that we have so far doesn’t necessarily suggest that. For many of these devices, we just don’t know, but the ones that we do know about appear to perform similarly.

I’d say the other misconception is people say, “My watch tracks my sleep.” Your watch doesn’t track sleep: your watch tracks your heart rate or your pulse, and your watch tracks movement. And then, math estimates your sleep from that device. So, that’s a big misconception of people telling me in the clinic, “My device is telling me I don’t have REM, so my sleep is really bad.” Sleep stages like REM, NREM are polysomnography EEG constructs. So, to use a consumer wearable sleep tracker’s components of dream sleep, light sleep, deep sleep, interchangeably with PSG-defined states— we’re just not there yet in my opinion.

I do think the estimates are getting better, and they do use properties of heart rate variability that we know change in the different sleep stages, but still, those [stages] are defined by brainwaves and eye movements. So, it’s very hard to recapitulate that. The question is, “Do we even need to track that on a daily basis?” What we’re really looking for, and what the clinical and research world wants, is to track on a longitudinal basis— objectively— just sleep-wake patterns day to day.

How do sleep trackers fit in with sleep clinics right now?

People sometimes think that doctors just don’t want to look at sleep wearable data because we don’t like it—that’s not true. A lot of us love seeing this data and love seeing sleep patterns over time, particularly if a patient can tell me “Hey you know, you treated my sleep apnea with this CPAP machine, and look at the change in my wearable tracked sleep.” One of the massive problems, though, is that clinical practices are really, really busy. We have a lot of patients that need help, and we need to give everybody high-quality care.

This means we have a high volume of work and most of our work takes place through something called the Electronic Health Record, and at this point, there is no real way to interface the data that comes from consumer wearable devices with that Electronic Health Record. So, we really don’t have a good way of integrating any of this into our clinical practice. It’s not that we are absolutely opposed to using this as an adjunct, particularly the ones that have some idea about performance, but we don’t really have a way of getting it in there to make it an easy part of our workflow. Patients will send me screenshots, or they will show me their app in the clinic.

I think medicine moves slower than consumer-geared technologies for a multitude of reasons, including security issues, but I do think that one day we will get there. And again, we’re not using these as diagnostic tools; we’re using them as an adjunct to our clinical decision-making. So, as long as they are reasonably accurate, and we overall know how they work, I think a lot of doctors would like to adapt them into their practice as long as we have a way of seamlessly integrating that data into our workflow.

Do you think we’re going to see circadian rhythms enter the clinic more in the near future?

Yeah, and what I would hope is that they don’t just enter the sleep clinic, but they enter the wellness and general health area as well. I think a lot of us are doing all of our body systems a big disservice by living in desynchrony with both our central clock and peripheral clocks.

When my friends and family ask, “What are some of the best things I can do for my sleep and circadian health?” I say “Wake up at the same time every single day.” That’s going to entrain your circadian phase. And hopefully, you’re eating in line with that (and you’re not eating when you’re supposed to be asleep), and when you’re getting light when you wake up. We are all undergoing mild degrees of circadian disruption by varying our wake-up time and getting as much light at night as we are.

Definitely. Especially with screens. I was one of the people who thought my phone screen couldn’t possibly affect my quality of sleep.

Exactly! And I think people are becoming more aware. I mean when you talk about intermittent fasting, that’s kind of a chronotherapeutic measure. It’s so simple, but people get so excited about it. It’s like yeah, don’t eat when your body is biologically prepared to be asleep.

You’re right that it’s incredibly simple, and I think people really respond to small changes that make a big effect on their health and wellness.

And it’s not magical, it’s timing. It’s literally all about timing.

What do you believe the future holds for sleep technology? What are you most excited about?

I’m just hopeful for a day where we change the way clinical evaluation works now, where a patient might be waiting for me to see them for months and months, and then I see them, give them instructions, send them home with sleep logs so I can see how they’re doing, and tell them to come back to the clinic in 6 months because I’m booked out I can’t see them sooner.

I want to get to a point where I see them, and at that initial point of care I know what their last 6 months of sleep looked like, and then I can come up with an intervention that’s precise for them and that’s also adaptive based on how their sleep looks in response to intervention.

Then possibly, when they do go home, we can change that intervention, maybe in an automated way, maybe with me being able to interact with an app, whatever it may be – but instead of writing down instructions and giving people medications, we’re using the mobile application as a prescription to really make patient-specific interventions that are based on wearable data.

So, it’s important to make it less labor-intensive for the patient because then it’s less likely to be done correctly or be done at all.

Exactly, we’re talking about behavior change here. That’s one of the cornerstones of so many diseases we take care of in medicine: they’re due to things that with behavior change could be different, and behavior change is hard. One of the behaviors that we’re really, really good at in current society is working with our devices and our apps. So, I think it’s just a no-brainer as far as delivery goes, I think it’s really time to make this stuff an adjunct and a helper in healthcare.

What have you seen in the clinic in the age of COVID?

I’ve seen a dichotomy. I mean I don’t think we’ve ever collectively (people my age, middle age, most of my patients) have gone through a stressor like this. So, there are quite a few people who had significant insomnia; there are people that had COVID that had major health disruptions during and following that, including fatigue during the day. Then there are people who actually had marked improvements in their sleep because they can sleep according to their clock, and they have more time due to less commute and so they can extend their sleep a bit.

There have actually been patients who go off alertness-promoting medications, and are a bit happier with their sleep. There was a great article about a gentleman who had always felt confined to the service industry because he was a night owl. He was always kind of stuck, like a bartender/server, and during COVID (because hours were more flexible with work from home), he was able to go into other industries and have regular hours at the time he selected, and have a more stable work path. Which is what he wanted. You know, we shouldn’t chronotype shame people. Just because you’re biologically late you shouldn’t be at a disadvantage in life, and that’s helped a lot of people’s sleep.

It’s nice to hear some good news come out of the year 2020. That’s all the questions I had lined up, but do you have anything you would like to add?

I think there’s also, what can wearables NOT do. So, we don’t know how accurate the oximetry is yet, we don’t use this as a way to diagnose sleep apnea, I don’t think that sleep staging is something we should rely on. It’s that sleep disordered breathing, is not really something we have not been able to pick up yet, so when people have some episodes of sleep snoring or gasping, feeling sleepy during the day – even if your wearable says you sleep great, that is a limitation and you should still see your doctor.

So, if you feel something isn’t right, it’s best to go in and talk to your doctor.

Exactly, trust your body. The manifestation of diseases is how you feel, not just how your numbers are.