Feasibility of Blood Pressure Measurement through Wearable Devices: Analysis of Smartwatches Performance

Abnormal changes in blood pressure (BP) values can result in hypertension, one of the most serious cardiovascular risk factors. For this reason, it is important to regularly monitor the BP changes. Wearable devices, such as smartwatches, enable the BP values recording during daily activities, enhancing the prevention and management of several diseases. However, data quality can be lower than the one provided by a medical-grade instrument. The aim of this study is to compare the BP values obtained by three commercial smartwatches to those obtained by an automatic sphygmomanometer, adopted as a reference device. Nineteen healthy subjects were enrolled to collect BP values in this study. Results show that blood pressure can be tracked, with certain precision and accuracy, using a wrist-worn wearable device. Among the tested smartwatches, the Omron HeartGuide resulted the most accurate to detect the systolic BP values, SBP (bias, $\mu_{SBP}=0.60$ mmHg), while the Samsung Galaxy Watch3 showed the highest accuracy for the systolic BP values and the highest precision (confidence intervals for systolic and diastolic BP, DBP, CI95%SBP = [−9.70; 10.91] mmHg; $\text{CI}95\%_{DBP}=[-4.68;7.57]$ mmHg), with respect to the accuracy of the sphygmomanometer (± 3 mmHg).