COMPARISON OF A CUFFLESS AND A CONVENTIONAL OSCILLOMETRIC CUFF-BASED DEVICE FOR NIGHT-TIME BLOOD PRESSURE MONITORING IN ADULTS

Objective: Cuffless blood pressure devices have shown promise in estimating daytime blood pressure. However, estimating night-time blood pressure remains more challenging. This study aimed to assess the capability of a photoplethysmography-based cuffless blood pressure device to estimate blood pressure during night-time sleep compared to a validated conventional cuff-based oscillometric device (reference device). Design and method: Thirty-nine adults, including healthy individuals and medically treated hypertensive patients with both normal and elevated blood pressure, underwent 24-hour ambulatory blood pressure monitoring with a reference device on the dominant upper arm and the cuffless device on the non-dominant upper arm. We calculated the difference between average awake and asleep blood pressure (awake-asleep blood pressure change) for both devices, and used the differences between them for further analysis. Additionally, Pearson correlation coefficients were determined for awake-asleep blood pressure changes between the cuffless and reference device. Results: The cuffless device achieved a mean difference (standard deviation) of 1.5 (5.9) mmHg for systolic blood pressure and -0.1 (4.0) mmHg for diastolic blood pressure in awake-asleep blood pressure changes compared to the reference. The agreement between the two devices in awake-asleep blood pressure changes is presented with Bland-Altman plots with bias (red dashed lines) and 95% limits of agreement (blue dashed lines) (Figure). The correlation coefficients were 0.72 for systolic blood pressure and 0.79 for diastolic blood pressure. During sleep, the mean differences (standard deviation) in systolic/diastolic blood pressures between the two devices were -0.4 (6.0) /0.7 (4.1) mmHg.Conclusions: The cuffless device demonstrated the ability to track blood pressure changes during sleep. Although further research and technological development is necessary, these findings are promising for the clinical application of cuffless devices in 24-hour ambulatory blood pressure monitoring.