Is the Blood Pressure-Enabled Smartwatch Ready to Drive Precision Medicine? Supporting Findings From a Validation Study

Abstract

Background: The popular wrist-worn wearables recording a variety of health metrics such as blood pressure (BP) in real time could play a potential role to advance precision medicine, but these devices are often insufficiently validated for their performance to enhance confidence in its use across diverse populations. The accuracy of BP-enabled smartwatch is assessed among the multi-ethnic Malaysians, and findings is discussed in comparison with conventional automated upper-arm BP device.

Methods: Validation procedures followed the guidelines by the Association for the Advancement of Medical Instrumentation/European Society of Hypertension/International Organization for Standardization (AAMI/ESH/ISO) Universal Standard (ISO 81060-2:2018). Quota sampling was employed to obtain eligible patients with normal and abnormal BP as per guideline. The measurements of BP were taken at wrist using HUAWEI WATCH D (test BP); and the readings were assessed against reference BP by the mercury sphygmomanometer. Agreement statistics and linear regression analyses were performed.

Results: BP measurements (234 data pairs) from 78 patients that fulfilled AAMI/ESH/ISO protocol were analyzed. The BP readings taken by the HUAWEI WATCH D were comparable to reference BP by sphygmomanometer based on 1) Criterion 1: systolic blood pressure (SBP) = -0.034 (SD 5.24) and diastolic blood pressure (DBP) = -0.65 (SD 4.66) mm Hg; and 2) Criterion 2: SBPs = -0.034 (SD 4.18) and DBPs = -0.65 (SD 3.94) mm Hg. Factors of sociodemographic characteristics, anthropometric measurements, cardiovascular comorbidities, and wrist hair density were not significantly associated with the mean BP differences.

Conclusions: HUAWEI WATCH D fulfilled criteria 1 and 2 of the AAMI/ESH/ISO Universal Standard (ISO 81060-2:2018) guidelines. It can be recommended for clinical use across a wider population. The rich data from real-time BP measurements in concurrent with other health-related parameters recorded by the smartwatch wearable offer opportunities to drive precision medicine in tackling therapeutic inertia by personalizing BP control regimen.

Keywords: Blood pressure; Precision health; Precision medicine; Smartwatch; Validation; Wearables; mHealth.

Figure 1

Bland-Altman scatter plots and results of the mean differences between watch device and the reference BPs for the systolic blood pressure (SBP) (a) and diastolic blood pressure (DBP) (b). SD: standard deviation; CI: confidence interval.

Figure 2

Bland-Altman scatter plots on mean difference between watch device and the reference BPs for the SBP (a) and DBP (b) by Malay, Chinese and Indian ethnic groups.