Higher sensitivity monitoring of reactions to COVID-19 vaccination using smartwatches

Abstract

More than 12 billion COVID-19 vaccination shots have been administered as of August 2022, but information from active surveillance about vaccine safety is limited. Surveillance is generally based on self-reporting, making the monitoring process subjective. We study participants in Israel who received their second or third Pfizer BioNTech COVID-19 vaccination. All participants wore a Garmin Vivosmart 4 smartwatch and completed a daily questionnaire via smartphone. We compare post-vaccination smartwatch heart rate data and a Garmin-computed stress measure based on heart rate variability with data from the patient questionnaires. Using a mixed effects panel regression to remove participant-level fixed and random effects, we identify considerable changes in smartwatch measures in the 72 h post-vaccination even among participants who reported no side effects in the questionnaire. Wearable devices were more sensitive than questionnaires in determining when participants returned to baseline levels. We conclude that wearable devices can detect physiological responses following vaccination that may not be captured by patient self-reporting. More broadly, the ubiquity of smartwatches provides an opportunity to gather improved data on patient health, including active surveillance of vaccine safety.

Fig. 1. Summary of symptoms as reported in the questionnaires after the third vaccination.

Percentage of all participants classified into each severity tier based on their most severe reported symptom in the 72 h following vaccination (a), percentage of all participants reporting each of the severe symptoms (b), and percentage of patients reporting each of the mild symptoms (c). Error bars represent 95% confidence intervals.

Fig. 2. Change in heart rate and stress measure as a function of reaction severity.

Mean difference in heart rate (in beats per minute) and stress measure (in points) between the post-vaccination and baseline periods in Garmin smartwatch data in the 72 h after the third vaccination, stratified by self-reported reaction severity. Error bars represent 95% confidence intervals.

Fig. 3. Change in heart rate and reaction severity for each hour after vaccination.

Mean difference in heart rate (in beats per minute) and stress measure (in points) between the post-vaccination and baseline periods in Garmin smartwatch data after the third vaccination, by hour, for individuals who reported no reaction (a and b), mild reaction (c and d), and severe reaction (e and f) in the self-reported questionnaires. Shaded regions represent 95% confidence intervals.