According to new research published in npj Digital Medicine, researchers from John Hopkins Medicine have found that data from wearable activity trackers can be used to evaluate cardiovascular health status. Researchers claim that although the usage of wearable sensors has increased dramatically in recent years, their primary function is still to count daily steps. The purpose of this study was to demonstrate that wearable activity trackers can be used to collect clinically significant parameters other than daily step count.
“The purpose of this study was to show that clinically relevant metrics beyond daily step count can be derived from these wearable activity monitors,” says Zheng “Peter” Xu, Ph.D., the study’s first author and a postdoctoral fellow for inHealth, a strategic initiative to advance precision medicine at The Johns Hopkins University. “Historically, remote monitoring of a patient’s physical status has been challenging. We wanted to meet that challenge and see what kind of untapped information is contained within these devices that could help us support patients with PAH.”
The researchers analyzed data from the activity trackers of 22 Cleveland Clinic patients with pulmonary arterial hypertension (PAH). For the study, the patients wore the Fitbit tracker between two clinical visits. At both visits, Cleveland Clinic staff members recorded 26 health measurements from each participant, including heart rate readings, health-related quality of life ratings, and findings from the six-minute walk distance (6MWD) test, a standard aerobic endurance test. They next evaluated a number of parameters related to physical and cardiovascular health using the minute-to-minute step rate and heart rate data of the subjects. This data included the heart rate distribution, the number and duration of walks per week, and the outcomes from the 6MWD test’s analog version. For example, when the 26 metrics gathered during clinic visits were compared to the activity-tracker metrics, the researchers discovered a correlation between the fitness ratings based on activity-tracker data and the clinic-measured levels of NT-proBNP, a blood biomarker for heart failure. Overall, they discovered substantial variations among the 22 research participants in 18 of these parameters.
“Finding so many statistically significant differences in a relatively small cohort suggests to us that activity-tracker data may make it possible to identify surrogate markers of disease severity that can be monitored remotely,” said Peter Searson, PhD, senior author of the study and the Joseph R. and Lynn C. Reynolds professor at the Johns Hopkins University Whiting School of Engineering, in the press release. “These data could potentially contribute to the identification of patients who would benefit from more frequent clinic visits or specific medications.”