Although several indices of aortic pressure are associated with cardiovascular damage independent of brachial blood pressure (BP), those indices which enhance associations beyond brachial BP are uncertain. We aimed to identify those aortic pressure indices that best enhance brachial BP relations with end-organ measures.Design and method:
Aortic function was determined using radial applanation tonometry and SphygmoCor software in 1197 community participants. End-organ measures included left ventricular mass index (LVMI) (n = 812), carotid intima-media thickness (n = 622) and estimated glomerular filtration rate (n = 1178).Results:
Central aortic pulse pressure (PPc), aortic-to-brachial PP amplification (PPamp), aortic backward wave pressure (Pb), and the aortic reflection magnitude (RM = Pb/forward wave pressure), but neither aortic augmented pressures (Pa), nor index (AIx) were associated with all end-organ measures independent of brachial PP. In multivariate models with the inclusion of PPc or Pb, relations between brachial PP and end-organ measures or the presence of LV hypertrophy or chronic kidney disease were eliminated. In contrast, with the inclusion of brachial PP and PPamp or RM in multivariate models, brachial PP-end-organ relations were retained, whilst PPamp (p < 0.0005) and RM (p < 0.01 to < 0.0001) added significantly to the models. Relations between PPamp or RM and end-organ changes remained unchanged with further adjustments for aortic pulse wave velocity.Conclusions:
PPamp and RM, but not PPc, Pb, Pa, or AIx independently associate with and add to brachial PP associations with end-organ measures. Thus, PP amplification and the reflection magnitude, but not aortic pressures or augmentation indices may enhance risk prediction beyond brachial BP.