Abstract:

Objective To explore the correlation and agreement of augmentation index (AI) and central systolic blood pressure (CSBP) measured by two devices (Australia SphygmoCor System and Japan Omron HEM-9000AI). Methods Two hundred and twenty-four subjects without antihypertensive medications had AI and CSBP measurements by both devices of SphygmoCor and Omron HEM-9000AI at the same day. The correlation and agreement of AI and CSBP between two devices were explored with simple correlation analysis and Bland-Altman plots. The influencing factors for measurements of AI and CSBP by both devices were investigated by multivariate stepwise regression analysis. Results AI and CSBP measured by Omron device were significantly higher than those measured by SphygmoCor [（81.5±14.4）%  vs （77.6±16.2）%，P<0.001;（132.3±16.7） mmHg vs （121.4±14.4）mmHg, P<0.001\], and absolute differences in AI and CSBP amounted to (3.9±11.0)% and (10.9±11.0) mmHg respectively.  AI and CSBP measured by two devices were closely correlated (r=0.75, P<0.001; r=0.76, P<0.001). AI detected by both devices were influenced by age, gender, heart rate and mean arterial pressure （P<0.001）, and AI detected by SphygmoCor was also influenced by body mass index （P<0.05）. CSBP detected by Omron device was influenced by gender and body mass index （P<0.05）, and was not influenced by age （P>0.05）.CSBP detected by SphygmoCor was only influenced by age （P<0.01）. Conclusion Omron HEM-9000AI and SphygmoCor System have good agreement in AI measurements. Both devices can be used in large scale clinical and epidemiological studies. However, there is a large disparity in CSBP estimations between two devices, and one CSBP measurement can not be used to replace the other.

Key words: blood pressure, central artery, augmentation index