Abstract 9349: Wave Reflection but Not Arterial Stiffness is Much Highly Correlated with Ambulatory Blood Pressure Parameters Including Blood Pressure Variability and Morning Blood Pressure Surge

Abstract

Background: With growing evidences that blood pressure (BP) variability, daily BP peak or morning BP surge are independently related to organ damage and future cardiovascular events. We try to invest the role of arterial stiffness and wave reflection, cardiac output in the association of those ambulatory BP parameters. Methods: A sample of 1156 normotensive and untreated hypertensive Taiwanese participants (546 women aged 30-79 years) was drawn from a community-based survey. All participants were recorded with 24 hours ambulatory blood pressure monitors. Besides, serum laboratory data, carotid-femoral pulse wave velocity (PWV, current gold standard for arterial stiffness), amplitude of the backward pressure wave decomposed from a calibrated tonometry-derived carotid pressure waveform (Pb, a transit-time independent index for wave reflections), and hemodynamic data include cardiac output were collected. Results: Mean 24 hours, day, and night systolic blood pressure (SBP), diastolic blood pressure (DBP), SBP standard deviation (SBPsd), DBP standard deviation (DBPsd), are all highly correlated to Pb, PWV, cardiac output (CO) and augmented pressure (r=0.506,0.274, 0.167, 0.419, all p<0.01 with regard to 24 hour SBPsd). At multi-variates regression models, Pb remains the strongest predictor for early morning BP surge, SBPsd, and DBPsd even after adjusting possible confounders include age, sex, cholesterol, triglycerides, creatinine, and body weight index. Conclusion: Reflective wave Pb is the strongest independent factor for predicting daily BP variability, (SBPsd, DBPsd) and even mean-SBP, DBP, morning BP surge but not central arterial stiffness.