Abstract 1323: Arterial Elasticity is a Novel Risk Factor for Atherosclerosis and Coronary Heart Disease
Background: Atherosclerosis (athero) makes arteries thicker and less elastic. Two well-validated devices estimate systemic arterial elasticity from reflected waves by radial artery tonometry. Sphygmocor measures aortic augmentation index (AIx, inverse to elasticity), and the Hypertension Diagnostics HDI 1000 provides small- and large-artery elasticity indices (SAEI, LAEI). Despite likely loss of elasticity with athero progression, relationships among AIx, SAEI, and LAEI, and between them and athero, are nearly unknown.
Methods: Among 1477 men and women, AIx, SAEI and LAEI and standard risk factors (RFs) of coronary heart disease (CHD), were assessed by multiple logistic regression (MLR) and ANCOVA for associations with athero: CHD (clinical history of MI, CABG, PTCA), carotid artery intima-media thickness (CIMT) by ultrasound (mean or plaque: max ≥1.2 mm), coronary and abdominal aortic calcium (CAC, AAC) scores.
Results: SAEI correlated strongly with AIx (r=−0.57, p <.0001). LAEI correlated less well with AIx (r=−0.39, p <.0001) and SAEI (r=0.38, p <.0001). Increased AIx and decreased SAEI and LAEI associated with increasing age, non-HDL-C, LDL-C, hypertension, and lower HDL-C and female sex by ANCOVA (all p <0.0001). AIx correlated with CHD, and SAEI with carotid plaque by MLR, while SAEI correlated with carotid thickness (CIMT means) by ANCOVA (table⇓). LAEI did not correlate with athero or CHD. AIx, SAEI and LAEI did not correlate with arterial calcium (CAC & AAC).
Conclusions: For the first time, we have shown that AIx, SAEI and LAEI
are interrelated but independent, and may measure different aspects of arterial elasticity,
correlate strongly with and may mediate effects of standard RFs on athero,
physiologically confirm anatomical arterial thickness (CIMT), but not arterial calcium, and most importantly
add to prediction of athero and CHD by standard RFs.
AIx and SAEI are promising tools for research and clinical assessment of arterial health.