Comparative accuracies of automated and manual office blood pressure measurements in a Chinese population.

Abstract

We aimed to assess the difference in the accuracy of readings from automated office blood pressure machines with each other or with manual office blood pressure measurements in Chinese individuals. We collected awake 48-h ambulatory blood pressure monitoring, two automated office blood pressure device (BpTRU and WatchBP) readings, and manual office blood pressure measurements in Chinese patients (n = 135) with hypertension in a randomized sequence. Differences were compared using paired t-tests and Bland-Altman plots. The sensitivity and specificity of the techniques for detecting elevated blood pressure were calculated using awake ambulatory blood pressure monitoring as the reference standard. The WatchBP device's and awake ambulatory blood pressure readings were similar. The BpTRU device provided significantly lower mean systolic (P < 0.001) and diastolic (P < 0.001) blood pressure readings, while manual office BP provided significantly higher mean systolic (P = 0.008) and diastolic (P < 0.001) blood pressure readings than the awake automated office blood pressure readings. Automated and manual office blood pressure measurements showed similar sensitivity, specificity, and 95% limits of agreement as based on Bland-Altman plots. The mean systolic (P < 0.001) and diastolic (P < 0.02) blood pressure readings of WatchBP and BpTRU differed, and their diagnostic performances were not superior than those of manual office blood pressure measurements in Chinese patients. Therefore, automated office blood pressure measurements cannot be routinely recommended for Chinese individuals in clinical practice. More studies are needed to confirm these results.