Smartwatches: These ubiquitous wearables have become a powerful tool for diagnosis and health monitoring in areas ranging from cardiology to diabetes to the effects of a COVID-19 vaccine.

The K’Watch measures glucose levels by analyzing interstitial fluid (ISF) through micropoints. (Credit: PKvitality)

Glucose monitoring is essential for the millions of people with diabetes. PKvitality, a French company specializing in biowearable health and sports, recently presented the results of firstin-human trial of its K’Watch Glucose, a continuous glucose monitoring device in the form of a smartwatch. According to the company, the system measures glucose levels by analyzing interstitial fluid (ISF) through micropoints. The system enables a painless and nonstigmatizing experience, solving the adhesive issue in a design-to-cost architecture.

The trial showed great user experience and tracking. It took place at AMCR Institute, a clinical research center focused on diabetes and obesity with worldwide renowned medical device expertise in the metabolic area.

“PKvitality is a unique blend of consumer electronic and medtech expertise, bringing the best of both worlds: appealing product, ease of use at the service of the diabetes patients,” says Luc Piérart, CEO of PKvitality.

Similarly, a recent study from Scripps Research demonstrates how data from wearable sensors, such as smartwatches and fitness bands, can also track a person’s physiological response to the COVID-19 vaccination. For the Scripps study, researchers drew their data from a larger project called Digital Engagement and Tracking for Early Control and Treatment (DETECT), which was launched in March 2020 in response to the emergence and rapid spread of SARS-CoV-2, the virus that causes COVID-19. DETECT is a mobile-app research platform that allows participants to share physiological and behavioral data gathered through a fitness band or smartwatch, as well as manually entered symptoms, test results, and vaccination status.

To determine whether consumer wearables could unearth digital biomarkers of vaccine-induced immune response, the Scripps scientists analyzed DETECT sensor data from two weeks before and after each vaccination dose. They compared post-vaccination changes to the participants’ resting heart rate, sleep, and activity levels to their baselines.

“DETECT really shows the power of wearable sensor data in furthering our understanding of multiple facets of COVID-19,” says Giorgio Quer, PhD, director of Artificial Intelligence at the Scripps Research Translational Institute. “We hope to continue to expand this research by growing our study cohort further, which will allow us to delve into important questions regarding breakthrough infections and other areas that are currently poorly understood.”

The study analyzed sensor data on sleep, activity, and heart rate from over 5,600 individuals. Among the findings, the team showed that the average resting heart rate of participants significantly increased the day following vaccination. The effect appeared to be stronger after the second dose of the Moderna vaccine, compared to the Pfizer-BioNTech vaccine, and more pronounced in younger individuals.

The analysis showed that the resting heart rate of study participants peaked two days post-vaccination and returned to normal four days after the first dose and six days after the second. In addition to increases in resting heart rate being higher after the second dose of the Moderna versus the Pfizer-BioNTech vaccine, the study suggests that prior COVID-19 infection was linked with a significantly higher resting heart rate increase after the first vaccine dose relative to those without prior infection. This increase is consistent with an expected greater immune response for these individuals.

The findings also show that women experienced greater changes than men in resting heart rate in the five days following vaccination after the first dose, and that individuals under the age of 40 had higher changes in resting heart rate than older individuals, but only after the second dose. Activity and sleep patterns appeared to be minimally affected by the first dose, but a significant decrease in activity and an increase in sleep relative to baseline were observed immediately after the second vaccine dose.

Another study, which involved more than 2.8 million participants, is the largest study to date to demonstrate how wearable consumer technologies can be used to screen for heart problems during everyday activities. Researchers screened a subset of participants for obstructive sleep apnea and found that people flagged for possible sleep apnea were 1.5 times more likely to have AFib than those who were not. According to the study, this finding suggests that tools suitable for detecting the two conditions can work synergistically to further enhance health monitoring.

“Digital technologies make it possible to increase general awareness about AFib and its risk factors as well as to improve prevention of AFib and its complications,” says Yutao Guo, MD, professor of internal medicine at Chinese PLA Medical School and Chinese PLA General Hospital in Beijing and the study’s lead author. “With the global surge of wearable technology for AFib screening, especially in the challenging setting of the COVID-19 pandemic, the present study provides a possible solution to help people identify possible signs of AFib and get diagnosed and treated earlier.”

Sherrie Trigg

Editor and Director of Medical Content