Smartwatches can track COVID-19 symptoms, study finds
If a COVID-19 infection develops, a wearable device may eventually be able to clue you in. A study at the University of Michigan found that a smartwatch can monitor how symptoms progress.
The study evaluated the effects of COVID-19 with various factors derived from heart-rate data. This method also could be employed to detect other diseases, such as influenza and the common cold, at home or when medical resources are limited, such as during a pandemic or in developing countries.
Tracking students and medical interns across the country, the University of Michigan researchers found that new signals embedded in heart rate indicated when individuals were infected with COVID-19 and how ill they became.
For instance, they discovered that individuals with COVID-19 experienced an increase in heart rate per step after the onset of their symptoms. Meanwhile, people who reported a cough as one of their COVID-19 symptoms had a much more elevated heart rate per step than those without a cough.
“We previously developed a variety of algorithms to analyze data from wearable devices. So, when the COVID-19 pandemic hit, it was only natural to apply some of these algorithms to see if we can get a better understanding of disease progression,” says Caleb Mayer, a doctoral student in mathematics at the University of Michigan and a co-first author of the study.
People may not internally sense COVID-19’s direct impact on the heart, but “heart rate is a vital sign that gives a picture of overall health," says Daniel Forger, a University of Michigan professor.
Millions of people are tracking their heart rate through wearable devices. This information is already generating a tremendous amount of data for researchers to analyze, says co-author Daniel Forger, professor of mathematics and research professor of computational medicine and bioinformatics at the University of Michigan.
“Heart rate is affected by many different physiological signals,” Forger explains. “For instance, if your lungs aren’t functioning properly, your heart may need to beat faster to meet metabolic demands. Your heart rate has a natural daily rhythm governed by internal biological clocks.” While people may not internally sense COVID-19’s direct impact on the heart, he adds that “heart rate is a vital sign that gives a picture of overall health.”
Among the total of 2,164 participants who enrolled in the student study, 72 undergraduate and graduate students contracted COVID-19, providing wearable data from 50 days before symptom onset to 14 days after. The researchers also analyzed this type of data for 43 medical interns from the Intern Health Study by the Michigan Neuroscience Institute and 29 individuals (who are not affiliated with the university) from the publicly available dataset.
Participants could wear the device on either wrist. They also documented their COVID-19 symptoms, such as fever, shortness of breath, cough, runny nose, vomiting, diarrhea, body aches, loss of taste, loss of smell, and sore throat.
Experts not involved in the study found the research to be productive. “This work is pioneering and reveals exciting new insights into the many important ways that we can derive clinically significant information about disease progression from consumer-grade wearable devices,” says Lisa A. Marsch, director of the Center for Technology and Behavioral Health and a professor in the Geisel School of Medicine at Dartmouth College. “Heart-rate data are among the highest-quality data that can be obtained via wearables.”
Beyond the heart, she adds, “Wearable devices are providing novel insights into individuals’ physiology and behavior in many health domains.” In particular, “this study beautifully illustrates how digital-health methodologies can markedly enhance our understanding of differences in individuals’ experience with disease and health.”
Previous studies had demonstrated that COVID-19 affects cardiovascular functions. Capitalizing on this knowledge, the University of Michigan endeavor took “a giant step forward,” says Gisele Oda, a researcher at the Institute of Biosciences at the University of Sao Paulo in Brazil and an expert in chronobiology—the science of biological rhythms. She commends the researchers for developing a complex algorithm that “could extract useful information beyond the established knowledge that heart rate increases and becomes more irregular in COVID patients.”
Wearable devices open the possibility of obtaining large-scale, long, continuous, and real-time heart-rate data on people performing everyday activities or while sleeping. “Importantly, the conceptual basis of this algorithm put circadian rhythms at the center stage,” Oda says, referring to the physical, mental, and behavioral changes that follow a 24-hour cycle. “What we knew before was often based on short-time heart rate measured at any time of day,” she adds, while noting that heart rate varies between day and night and also changes with activity.
However, without comparison to a control group of people having the common flu, it is difficult to determine if the heart-rate signals are unique to COVID-19 or also occur with other illnesses, says John Torous, an assistant professor of psychiatry at Harvard Medical School who has researched wearable devices. In addition, he points to recent data showing that many wearables, which work by beaming light through the skin, may be less accurate in people with darker skin due to variations in light absorption.
While the results sound interesting, they lack the level of conclusive evidence that would be needed to transform how physicians care for patients. “But it is a good step in learning more about what these wearables can tell us,” says Torous, who is also director of digital psychiatry at Beth Israel Deaconess Medical Center, a Harvard affiliate, in Boston. A follow-up step would entail replicating the results in a different pool of people to “help us realize the full value of this work.”
It is important to note that this research was conducted in university settings during the early phases of the pandemic, with remote learning in full swing amid strict isolation and quarantine mandates in effect. The findings demonstrate that physiological monitoring can be performed using consumer-grade wearable sensors, allowing research to continue without in-person contact, says Sung Won Choi, a professor of pediatrics at the University of Michigan who is principal investigator of the student study.
“The worldwide COVID-19 pandemic interrupted a lot of activities that relied on face-to-face interactions, including clinical research,” Choi says. “Mobile technology proved to be tremendously beneficial during that time, because it allowed us to collect detailed physiological data from research participants remotely over an entire semester.” In fact, the researchers did not have any in-person contact with the students involved in the study. “Everything was done virtually," Choi explains. "Importantly, their willingness to participate in research and share data during this historical time, combined with the capacity of secure cloud storage and novel mathematical analytics, enabled our research teams to identify unique patterns in heart-rate data associated with COVID-19.”
How Excessive Regulation Helped Ignite COVID-19's Rampant Spread
When historians of the future look back at the 2020 pandemic, the heroic work of Helen Y. Chu, a flu researcher at the University of Washington, will be worthy of recognition.
Chu's team bravely defied the order and conducted the testing anyway.
In late January, Chu was testing nasal swabs for the Seattle Flu Study to monitor influenza spread when she learned of the first case of COVID-19 in Washington state. She deemed it a pressing public health matter to document if and how the illness was spreading locally, so that early containment efforts could succeed. So she sought regulatory approval to adapt the Flu Study to test for the coronavirus, but the federal government denied the request because the original project was funded to study only influenza.
Aware of the urgency, Chu's team bravely defied the order and conducted the testing anyway. Soon they identified a local case in a teenager without any travel history, followed by others. Still, the government tried to shutter their efforts until the outbreak grew dangerous enough to command attention.
Needless testing delays, prompted by excessive regulatory interference, eliminated any chances of curbing the pandemic at its initial stages. Even after Chu went out on a limb to sound alarms, a heavy-handed bureaucracy crushed the nation's ability to roll out early and widespread testing across the country. The Centers for Disease Control and Prevention infamously blundered its own test, while also impeding state and private labs from coming on board, fueling a massive shortage.
The long holdup created "a backlog of testing that needed to be done," says Amesh Adalja, an infectious disease specialist who is a senior scholar at the Johns Hopkins University Center for Health Security.
In a public health crisis, "the ideal situation" would allow the government's test to be "supplanted by private laboratories" without such "a lag in that transition," Adalja says. Only after the eventual release of CDC's test could private industry "begin in earnest" to develop its own versions under the Food and Drug Administration's emergency use authorization.
In a statement, CDC acknowledged that "this process has not gone as smoothly as we would have liked, but there is currently no backlog for testing at CDC."
Now, universities and corporations are in a race against time, playing catch up as the virus continues its relentless spread, also afflicting many health care workers on the front lines.
"Home-testing accessibility is key to preventing further spread of the COVID-19 pandemic."
Hospitals are attempting to add the novel coronavirus to the testing panel of their existent diagnostic machines, which would reduce the results processing time from 48 hours to as little as four hours. Meanwhile, at least four companies announced plans to deliver at-home collection tests to help meet the demand – before a startling injunction by the FDA halted their plans.
Everlywell, an Austin, Texas-based digital health company, had been set to launch online sales of at-home collection kits directly to consumers last week. Scaling up in a matter of days to an initial supply of 30,000 tests, Everlywell collaborated with multiple laboratories where consumers could ship their nasal swab samples overnight, projecting capacity to screen a quarter-million individuals on a weekly basis, says Frank Ong, chief medical and scientific officer.
Secure digital results would have been available online within 48 hours of a sample's arrival at the lab, as well as a telehealth consultation with an independent, board-certified doctor if someone tested positive, for an inclusive $135 cost. The test has a less than 3 percent false-negative rate, Ong says, and in the event of an inadequate self-swab, the lab would not report a conclusive finding. "Home-testing accessibility," he says, "is key to preventing further spread of the COVID-19 pandemic."
But on March 20, the FDA announced restrictions on home collection tests due to concerns about accuracy. The agency did note "the public health value in expanding the availability of COVID-19 testing through safe and accurate tests that may include home collection," while adding that "we are actively working with test developers in this space."
After the restrictions were announced, Everlywell decided to allocate its initial supply of COVID-19 collection kits to hospitals, clinics, nursing homes, and other qualifying health care companies that can commit to no-cost screening of frontline workers and high-risk symptomatic patients. For now, no consumers can order a home-collection test.
"Losing two months is close to disastrous, and that's what we did."
Currently, the U.S. has ramped up to testing an estimated 100,000 people a day, according to Stat News. But 150,000 or more Americans should be tested every day, says Ashish Jha, professor and director of the Harvard Global Health Institute. Due to the dearth of tests, many sick people who suspect they are infected still cannot get confirmation unless they need to be hospitalized.
To give a concrete sense of how far behind we are in testing, consider Palm Beach County, Fla. The state's only drive-thru test center just opened there, requiring an appointment. The center aims to test 750 people per day, but more than 330,000 people have already called to try to book a slot.
"This is such a rapidly moving infection that losing a few days is bad, and losing a couple of weeks is terrible," says Jha, a practicing general internist. "Losing two months is close to disastrous, and that's what we did."
At this point, it will take a long time to fully ramp up. "We are blindfolded," he adds, "and I'd like to take the blindfolds off so we can fight this battle with our eyes wide open."
Better late than never: Yesterday, FDA Commissioner Stephen Hahn said in a statement that the agency has worked with more than 230 test developers and has approved 20 tests since January. An especially notable one was authorized last Friday – 67 days since the country's first known case in Washington state. It's a rapid point-of-care test from medical-device firm Abbott that provides positive results in five minutes and negative results in 13 minutes. Abbott will send 50,000 tests a day to urgent care settings. The first tests are expected to ship tomorrow.
Your Privacy vs. the Public's Health: High-Tech Tracking to Fight COVID-19 Evokes Orwell
The COVID-19 pandemic has placed public health and personal privacy on a collision course, as smartphone technology has completely rewritten the book on contact tracing.
It's not surprising that an autocratic regime like China would adopt such measures, but democracies such as Israel have taken a similar path.
The gold standard – patient interviews and detective work – had been in place for more than a century. It's been all but replaced by GPS data in smartphones, which allows contact tracing to occur not only virtually in real time, but with vastly more precision.
China has gone the furthest in using such tech to monitor and prevent the spread of the coronavirus. It developed an app called Health Code to determine which of its citizens are infected or at risk of becoming infected. It has assigned each individual a color code – red, yellow or green – and restricts their movement depending on their assignment. It has also leveraged its millions of public video cameras in conjunction with facial recognition tech to identify people in public who are not wearing masks.
It's not surprising that an autocratic regime like China would adopt such measures, but democracies such as Israel have taken a similar path. The national security agency Shin Bet this week began analyzing all personal cellphone data under emergency measures approved by the government. It texts individuals when it's determined they had been in contact with someone who had the coronavirus. In Spain and China, police have sent drones aloft searching for people violating stay-at-home orders. Commands to disperse can be issued through audio systems built into the aircraft. In the U.S., efforts are underway to lift federal restrictions on drones so that police can use them to prevent people from gathering.
The chief executive of a drone manufacturer in the U.S. aptly summed up the situation in an interview with the Financial Times: "It seems a little Orwellian, but this could save lives."
Epidemics and how they're surveilled often pose thorny dilemmas, according to Craig Klugman, a bioethicist and professor of health sciences at DePaul University in Chicago. "There's always a moral issue to contact tracing," he said, adding that the issue doesn't change by nation, only in the way it's resolved.
"Once certain privacy barriers have been breached, it can be difficult to roll them back again."
In China, there's little to no expectation for privacy, so their decision to take the most extreme measures makes sense to Klugman. "In China, the community comes first. In the U.S., individual rights come first," he said.
As the U.S. has scrambled to develop testing kits and manufacture ventilators to identify potential patients and treat them, individual rights have mostly not received any scrutiny. However, that could change in the coming weeks.
The American approach is also leaning toward using smartphone apps, but in a way that may preserve the privacy of users. Researchers at MIT have released a prototype known as Private Kit: Safe Paths. Patients diagnosed with the coronavirus can use the app to disclose their location trail for the prior 28 days to other users without releasing their specific identity. They also have the option of sharing the data with public health officials. But such an app would only be effective if there is a significant number of users.
Singapore is offering a similar app to its citizens known as TraceTogether, which uses both GPS and Bluetooth pings among users to trace potential encounters. It's being offered on a voluntary basis.
The Electronic Frontier Foundation, the leading nonprofit organization defending civil liberties in the digital world, said it is monitoring how these apps are developed and deployed. "Governments around the world are demanding new dragnet location surveillance powers to contain the COVID-19 outbreak," it said in a statement. "But before the public allows their governments to implement such systems, governments must explain to the public how these systems would be effective in stopping the spread of COVID-19. There's no questioning the need for far-reaching public health measures to meet this urgent challenge, but those measures must be scientifically rigorous, and based on the expertise of public health professionals."
Andrew Geronimo, director of the intellectual property venture clinic at the Case Western University School of Law, said that the U.S. government is currently in talks with Facebook, Google and other tech companies about using deidentified location data from smartphones to better monitor the progress of the outbreak. He was hesitant to endorse such a step.
"These companies may say that all of this data is anonymized," he said, "but studies have shown that it is difficult to fully anonymize data sets that contain so much information about us."
Beyond the technical issues, social attitudes may mount another challenge. Epic events such as 9/11 tend to loosen vigilance toward protecting privacy, according to Klugman and Geronimo. And as more people are sickened and hospitalized in the U.S. with COVID-19, Klugman believes more Americans will be willing to allow themselves to be tracked. "If that happens, there needs to be a time limitation," he said.
However, even if time limits are put in place, Geronimo believes it would lead to an even greater rollback of privacy during the next crisis.
"Once certain privacy barriers have been breached, it can be difficult to roll them back again," he warned. "And the prior incidents could always be used as a precedent – or as proof of concept."