It was at the start of the pandemic that my sleep monitor made me panic for the first time. I was testing SleepScore, Wirecutter’s choice for the best sleep tracker app, and I noticed that although most of my data from the night before (how much time I spent in light, deep, and REM sleep) was fairly normal, my breathing rate was twice as fast as usual . A quick Google search confirmed what I already knew: rapid breathing could be a symptom of respiratory illness. My mind jumped at the conclusion of the moment, “Oh my god I have the coronavirus.”
(Spoiler alert: I didn’t.)
It wouldn’t be the first time someone has turned to a sleep tracker for disease. Sleep trackers are designed to assess the quality of your sleep, typically by measuring how long you sleep and how much time you spend at each stage of sleep. But many sleep trackers, especially wearable sleep and activity trackers, collect much more data, including your nighttime heart rate, heart rate variability (HRV), body temperature and respiratory rate, as well as the duration of sleep. Researchers studied this wealth of data to see if they can identify changes (often subtle) in people’s baseline data that could predict the onset of infections like COVID-19, especially asymptomatic or pre-existing cases. symptomatic.
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Since 2014, Michael Snyder, PhD, professor of genetics at Stanford University who founded and consults various precision medicine companies, has been studying the potential of wearable sleep and fitness trackers (including the Oura ring, Fitbit trackers, and the Apple Watch) to detect disease, primarily using heart rate data. He even lucked out doing the methods on his own, detecting his own Lyme disease using a smartwatch: “Basically my heart rate went up and my blood oxygen dropped before I got there. don’t be symptomatic, ”he said.
Since the start of the pandemic, Snyder and his team have applied their research to detecting COVID-19. Recently the team published results demonstrating that by analyzing data collected from popular wearable sleep and fitness trackers, they could (on average) detect cases of COVID-19 four days before symptoms start and seven days before diagnosis. COVID-19 was not the only focus of the study – influenza and other respiratory illnesses were also detected two days before symptoms appeared.
Last year I reviewed the Oura ring, a wedding ring-like device that measures your heart rate, heart rate variability, breathing rate, and body temperature while you sleep. The Rockefeller Neuroscience Institute (RNI) at the University of West Virginia recently conducted a specific study on the ring’s ability to track COVID-19. When you are sick, your heart rate and respiratory rate are likely to increase, and the variability in your heart rate is likely to decrease. Using app, AI model, and data from Oura Ring, RNI reports, predicted cases of COVID-19 three days before symptoms appear, with greater than 90% accuracy (the study was not peer reviewed).
Meanwhile, at the University of California, San Francisco, researchers used the skin temperature monitoring capabilities of the Oura Ring to detect fever early (Oura Health provided less than 10% of the funding for the study, a company representative told us, and some of the researchers are associated with the company). In their first peer review study out of 50 Oura Ring wearers who ended up contracting COVID-19, 38 of them had an elevated temperature recorded by continuous monitoring of their tracker before they had symptoms that they could recognize. Due to the original promise of the Oura ring in detecting asymptomatic and pre-symptomatic COVID-19, the The NBA gave rings to players participate in the Orlando, Florida “bubble” last summer.
But for the potential of all these devices, there is a downside. A small university 2020 of Copenhagen study of 27 patients with chronic heart disease found that using a fitness tracker could increase anxiety, especially when wearers are not meeting their fitness goals or have alarming health indicators (this what I could relate to after my fear of the respiratory rate). Scientists concluded that for these devices to be the most useful, people needed the advice of medical professionals to correctly interpret the data.
And then there is the possibility that the device will take an incorrect reading, either due to a fault or user error. Perhaps this is what happened with my high reading, which was not, it turned out, an early sign of infection. My early morning health scare was probably the result of testing multiple sonar sleep trackers at once, an occupational hazard at Wirecutter. (With twice as many sonar waves reflected off my chest, it makes sense that my reading was wrong.)
After several months of testing these devices, I am ambivalent about their usefulness for this type of predictive health monitoring. At a time when I was already hyper-vigilant about my health, dealing with so much data from devices and apps became more annoying than reassuring. Clearly, reliable and accessible testing, safety precautions such as masking and vaccination are better ways to overcome the current pandemic. For now, I’ll continue to use sleep trackers to learn more about my sleep patterns and (maybe) to be notified when I might have a cold.