Correlation Between Smartwatch-based Blood Pressure Monitoring and Conventional Ambulatory Blood Pressure Monitoring

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.