In a first-of-its-kind study, researchers at Tel Aviv University fitted nearly 5,000 Israelis with smartwatches and monitored their physiological parameters for two years. Of those monitored, 2,038 received repeated doses of the coronavirus vaccine, which allowed researchers to objectively compare measures before and after vaccine administration and confirm the safety of the vaccine. In addition, the researchers, in collaboration with the Kahn Sagol Maccabi Center for Research and Innovation (KSM – Maccabi Health Services Research and Innovation Institute), investigated the safety of the booster by anonymously analyzing the medical files of 250,000 Maccabi Health Services members (de-identified details) and with the approval of the Helsinki Committee. Based on the analysis of this large amount of data, the researchers were able to assess the safety of vaccines from three perspectives: subjectively – as reported by the participant, objectively – as detected by the watch, and clinically – as diagnosed by the doctor.
The research was conducted by PhD student Matan Yechezkel under the guidance of Prof. Dan Yamin, Head of the Epidemic Research Lab, and in collaboration with Prof. Erez Shmuel, Head of the Big Data Lab, all from the Fleischman Faculty of Engineering. at Tel Aviv University. Other collaborators were Dr. Tal Patalon and Dr. Sivan Gazit, Director and Deputy Director of KSM, respectively, as well as Dr. Amichai Painsky and Ms. Merav Mofaz from Tel Aviv University. The results of the study were published in a prestigious journal Lancet Respiratory Medicine.
Prof. Yamin explains: “We wanted to test the safety of booster vaccines against the coronavirus. We conducted a large-scale two-year clinical trial in which we equipped 4,698 Israelis with smartwatches. The smartwatches were used to monitor a number of parameters such as heart rate, heart rate variability, sleep quality, daily steps and more. .In addition, participants were asked to complete daily questionnaires about their health status in a custom app we created.Finally, we analyzed data on possible unusual events from the medical records of a quarter of a million randomly selected, anonymous, insured members of Maccabi Health Services.
Because the medical file contains the date of the booster vaccination, the researchers were able to compare the condition of the vaccinated patient with his baseline condition 42 days before and 42 days after receiving the vaccine. Data were obtained from questionnaires, smart watches and records of the Maccabi Health Insurance Fund.
“We saw clear and significant changes after the vaccine, such as an increase in heart rate compared to the heart rate measured before vaccination,” says Prof. Yamin, “and then we saw the participants return to baseline, that is, the heart rate returned to the previous level six days after vaccination. So our study confirms the safety of the vaccine . The study also made it possible to compare the subjective and objective indicators and medical diagnosis of the same participant who received the first booster and a second boost a few months later. We found no difference in the physiological response recorded by the smartwatches or the physiological response reported by the participant in the app. In fact, the smartwatches were even more accurate.
The researchers noted that “the most surprising finding was that the watches were more sensitive than the people they were monitoring. Many participants reported feeling tired, headaches, etc. after receiving the vaccine, and after two or three days they felt normal and well. In contrast, their watches in the study, we saw clear changes in heart rate that continued for several days.There were also vaccinated participants who reported no side effects at all, but definitely experienced physiological changes based on the smartwatch data.In other words, we learned that the smartwatches were more sensitive to changes in general well-being than the participants themselves.
Twenty-five unusual side effects attributed to the Corona vaccine were reported in the medical literature, and researchers paid particular attention to looking for rare cases of inflammation of the heart muscle (myocarditis) and pericarditis. Prof. Yamin and his colleagues checked the incidence of these unusual side effects among a quarter of a million Maccabi members and found no increase in serious cases associated with the vaccination.
While the watch reports the minor changes in the muscles and the participant only reports the significant changes he feels, the medical file tells us both unusual events diagnosed by doctors and hospitalizations related to vaccinations, with an emphasis on heart disease. . We did a comprehensive analysis of all twenty-five of these unusual side effects, and we did not see an increase in their incidence among people receiving boosters. We found the vaccine to be safe to use. The smartwatch’s sensors “felt” that the vaccine was safe, the vaccinee self-reported that the vaccine was safe, and finally, doctors determined that the vaccine was safe. The results of the study have far-reaching implications for objective testing of vaccine safety in the future.
Prof. Dan Yamin, Head of Epidemiology Research Laboratory
Yechezkel, M., et al. (2022) Safety of the fourth COVID-19 BNT162b2 mRNA (second booster vaccine): a prospective and retrospective cohort study. Lancet Respiratory Medicine. doi.org/10.1016/S2213-2600(22)00407-6.