Daytime blood pressure measurements performed by a cuffless blood pressure monitor compared to 24-hour ambulatory blood pressure monitor: preliminary comparative results of a single-centre study

Abstract

Abstract Background Ambulatory blood pressure (BP) monitors (ABPM) measure systolic and diastolic BP (SBP, DBP), limited to 24-48-hour snapshots, using uncomfortable cuff-based oscillometric sphygmomanometers. Some cuffless BP devices overcome these limitations, supporting continual BP monitoring. There is currently intense debate whether cuffless devices generate data comparable to ABPM. Purpose Here, we present preliminary results of daytime BP measurements performed by a validated and commercially available cuffless BP monitor compared to 24-hour ABPM. Methods 52 out of 63 estimated total patients (NCT04548986, age 53.2±7.1 years, 18.9% female, arm circumference 28.5±2 cm) had been enrolled in a 12-week cardiac rehabilitation (CR) program. The patients used a validated, CE-marked, over-the-counter optical cuffless wrist BP monitor during the entire CR program, while 24-hour cuff-based ABPM was performed on the first and last day of the CR program. For each patient, average daytime (9am-9pm) SBP and DBP were calculated – and compared – for 1 day of ABPM and 7 days of cuffless monitor (session 1: ABPM first day vs. cuffless monitor first week; session 2: ABPM last day vs. cuffless monitor last week). Only sessions that had 20 or more valid daytime measurements on both modalities were included in the study. Results 50 patients (35 in session 1, 15 in session 2) had 20 or more valid daytime measurements on both modalities, and were included in the study. Bias between the cuffless monitor and ABPM for daytime DBP was (mean ± SD [95% CI] ) -2.2±8.0 [-4.5, 0.1] mmHg, R2 = 0.66 (Figure 1A), with agreements of 78% and 96% within ±10 mmHg (dark grey) and ±15 mmHg (light grey) regions of interest (ROI), respectively. Bias between the cuffless monitor and ABPM for daytime SBP was 1.6±10.5 [-1.5, 4.6] mmHg, R2 = 0.70 (Figure 1B), with agreements of 60% and 84% within the ±10/±15 mmHg ROI, respectively. Conclusions The results suggest that 1-week monitoring with the investigated cuffless monitor yields equivalent daytime BP values to 24-h ABPM, which supports the use of cuffless BP monitor for long-term, continual daytime BP monitoring. The present preliminary study is limited by the partially recruited population and daytime measurements only. Night-time analysis will be covered in subsequent studies.Figure 1