Cuffless wearable devices are currently being developed for long-term monitoring of blood pressure (BP) in patients with hypertension and in apparently healthy people. This study evaluated the feasibility and measurement stability of smartwatch-based cuffless BP monitoring in real-world conditions. Users of the first smartwatch-based cuffless BP monitor approved in Korea (Samsung Galaxy Watch) were invited to upload their data from using the device for 4 weeks post calibration. A total of 760 participants (mean age 43.7 ± 11.9, 80.3% men) provided 35,797 BP readings (average monitoring 22 ± 4 days [SD]; average readings 47 ± 42 per participant [median 36]). Each participant obtained 1.5 ± 1.3 readings/day and 19.7% of the participants obtained measurements every day. BP showed considerable variability, mainly depending on the day and time of the measurement. There was a trend towards higher BP levels on Mondays than on other days of the week and on workdays than in weekends. BP readings taken between 00:00 and 04:00 tended to be the lowest, whereas those between 12:00 and 16:00 the highest. The average pre-post calibration error for systolic BP (difference in 7-day BP before and after calibration), was 6.8 ± 5.6 mmHg, and was increased with higher systolic BP levels before calibration. Smartwatch-based cuffless BP monitoring is feasible for out-of-office monitoring in the real-world setting. The stability of BP measurement post calibration and the standardization and optimal time interval for recalibration need further investigation. [Figure not available: see fulltext.]
Bibliographical noteFunding Information:
MH, YRL, and TP wrote the draft. SI and WBP, the present and the immediate-past presidents of KSH, supported this study on behalf of the KSH. All authors reviewed and edited the manuscript. All authors have read and agreed to the published version of the manuscript. We thank Jongmin Choi and Sunok Jung (Samsung Electronics) for technical assistance in Galaxy Watch device instructions. Sang-Hyun Ihm5, Wook Bum Pyun6, Hae Young Lee1,2, Myeong-Chan Cho8
© 2023, The Author(s), under exclusive licence to The Japanese Society of Hypertension.
- Blood Pressure
- Cuffless Blood Pressure Measurement
- Wearable Device