Smartwatch ABPM vs. Conventional ABPM

Blood pressure (BP) monitoring outside of the medical care environment is an increasingly important part of clinical hypertension assessment and management. Ambulatory BP monitoring (ABPM) uses automatic detection and recording devices for repeated determinations during an extended period, typically 24 hours. This technique has been shown to substantially enhance the clinician's understanding of BP behavior in patients and aid in diagnosis and therapeutic decision making. The ABPM is superior to office BP in predicting target organ, hypertensive cerebrovascular disease, retinopathy, renal abnormalities, and alterations in vascular compliance.1-4) Most of these studies have also demonstrated that a loss of nocturnal decline in BP (so-called non-dipper) conveys excessive risk for stroke and myocardial infarction.

Although conventional ABMP is usually well tolerated by patients, a few problems do exist. A minority of patients do not sleep well with the recorders and tend to have somewhat higher BP values. Cuffs can also rotate, and different arm positions can change BP significantly. Rarely, patients may develop erythema, ecchymoses, petechiae, or superficial phlebitis in the area distal to cuff placement.

Recently, smartwatches that measure BP without a cuff have become available. Since these measurements are relatively more user-friendly than conventional cuff-based measurements, they may aid in more frequent BP monitoring. Currently, only one study compared a non-commercial armband wearable pulse transit time (PTT) system for 24-hour cuff-less BP measurement with ABPM.5) We will investigate the accuracy and precision of Samsung Smartwatch with ABPM in young, healthy volunteers.

Inclusion criteria

• Ambulatory healthy subjects
• Subjects aged 20 years or more
• Subjects willing to participate in this study voluntarily Exclusion criteria
• Subjects inability to provide informed consent
• Subjects with any medical history
• Subjects with irregular heart rhythm (e.g. atrial fibrillation, atrial flutter, or bigeminy)
• Subjects unable to wear a watch due to wrist circumference
• Subjects with BP difference 10mmHg or more between left and right arm