Pilot Study to Show Augmentation Index Variation with Posture in Non-Hypertensive Subjects Versus Hypertensive Patients on ACE Inhibitors

Abstract

Objectives: Augmentation index (AI), is a marker of arterial stiffness and cardiovascular mortality. The current study is focused on the variations in AI in both supine and sitting position for subjects with non-hypertension subjects versus patients with hypertension on ACE inhibitors or angiotension receptor blockers (ARBs), and to look for effects ACE inbitors or ARBs on postural variations in AI. Methods: This study was to analyse AI in both supine and sitting position for subjects without hypertension (n = 10) versus hypertensive patients on ACE inhibitors or ARBs (n = 10). Measurements were done by SphygmoCor which is the global gold standard for non-invasive central pressures assessment and AI. Differences between characteristics at supine and sitting position were compared using non-parametric paired test of Wilcoxon signed-rank test in normotensives and via paired t test and student's t test in hypertensive age group. A value of P < 0.05 was accepted as statistically significant. Results: In non-hypertensive subjects, aortic AI significantly increased from sitting to supine position (P < 0.05), whereas AI decreased significantly in supine position from sitting position in subgroup of patients on ACE inhibitors (P < 0.05). Conclusions: Our findings suggested that AI increased from sitting to supine position displayed in non-hypertensive subjects. On the other hand, in hypertensive patients on ACE inhibitors or ARBs, there is significant decrease in AI in supine position.