Accuracy of a Novel High-Throughput "Car Blood Pressure" Measurement Protocol.

Abstract

Background: More than one in three adults with hypertension in the United States are unaware of their condition, highlighting the importance of large-scale screening campaigns. Currently, the identification of hypertension is largely limited to medical settings. To help overcome this barrier, we developed a novel high-throughput screening protocol that measures blood pressure (BP) while patients remain seated in an automobile ("car-BP"). The aim of this study was to provide an initial assessment of the accuracy of car-BP.

Methods: Three BP readings were determined in a clinic exam room before and after three BP readings were taken while patients were seated in a parked car outside (n=100 participants). The same validated device model (Omron HEM-907XL) and BP measurement methods adhering to guidelines were used in both scenarios. The average of all 6 clinic readings was compared to the average of the 3 car-BP readings in each individual.

Results: Mean clinic and car-BP readings were 120.9 ± 16.2/78.0 ± 9.9 and 118.9 ± 15.2/76.0 ± 10.0 mm Hg, respectively. The paired mean and absolute mean differences in systolic BP levels between methods were -1.92 mm Hg (95% confidence interval (CI) -3.2 to -0.7 mm Hg) and 4.8 mm Hg (95%CI 3.8 to 5.6 mm Hg), respectively. A total of 85% of participants had both systolic and diastolic BP levels ≤10 mm Hg different between measurement scenarios (meeting the a priori determined study primary outcome).

Conclusions: Car-BP represents an innovative and accessible approach for potential large-scale hypertension screening campaigns.