ACCURACY AND BLOOD PRESSURE THRESHOLD CONTROL ANALYSIS OF UNATTENDED AUTOMATED OFFICE BLOOD PRESSURE MEASUREMENT: A CROSS-SECTIONAL STUDY BASED ON MULTICENTER POPULATIONS

Abstract

Objective: The emergence of unattended automated office blood pressure (u-AOBP) measurement, facilitated by the flourishing development of electronic blood pressure monitors, has been proposed as a potential alternative or complementary approach for assessing patients’ blood pressure status within clinical settings. However, robust evidence is lacking to determine its application in diagnosing hypertension within the clinical practice in China. This study aims to compare u-AOBP values with standard office blood pressure data, assess the correlation between u-AOBP and diagnostic thresholds. Design and method: The study involved participants recruited from October 2023 to February 2024 in three hospitals: People's Hospital of Gongyi City in Henan Province, Nangong City Hospital in Hebei Province, and Fuwai Hospital of the Chinese Academy of Medical Sciences. Standardized validated upper arm blood pressure monitors were used to measure blood pressure. Baseline demographic data, anthropometric measurements, u-AOBP, and standard office blood pressure data were collected, along with additional examination results, including echocardiograms and 24-hour ambulatory blood pressure monitoring. Results: 1. The difference between u-AOBP and awake dynamic average blood pressure was 1.34 mmHg (95% confidence interval: 0.88-3.55 mmHg), and the difference was not statistically significant (P = 0.236). 2. The optimal cutoff values for diagnosing elevated blood pressure using u-AOBP, determined by ROC curve analysis based on awake dynamic blood pressure measurements, were 130.75/83.75 mmHg (sensitivity 89.73%, specificity 27.27%). 3. In participants with a dipper blood pressure diurnal rhythm, there was no statistically significant difference between standard office blood pressure and u-AOBP measurements (P > 0.05). However, in the group including non-dipper rhythm participants, standard office blood pressure was higher than u-AOBP by 5.84/4.98 mmHg (P < 0.05). Conclusions: 1. Unattended automated blood pressure measurements can reduce, but not eliminate, the white coat effect, with an optimal cutoff value for diagnosing elevated blood pressure determined as 130.75/83.75 mmHg. 2. In individuals with a normal dipper blood pressure diurnal rhythm, standardized u-AOBP values are equivalent to standard office blood pressure.