Sex differences in the associations of hemodynamic load with left ventricular hypertrophy and concentric remodeling

BACKGROUND Left ventricular hypertrophy (LVH) and concentric remodeling are associated with adverse cardiovascular outcomes. We hypothesized that measures of arterial load are associated with LVH and concentric remodeling, and that associations differ by sex. METHODS We studied 600 non-Hispanic whites (59% women) belonging to hypertensive sibships. By integrating arterial tonometry with echocardiography, we obtained the following hemodynamic measures: aortic characteristic impedance (Z _c), proximal aortic compliance (PAC), systemic vascular resistance, augmentation index, and carotid-femoral pulse wave velocity (cfPWV). LVH and concentric remodeling were assessed by left ventricular mass indexed to body surface area (LVMI) and relative wall thickness (RWT), respectively. LVMI was log-transformed to reduce skewness. Hemodynamic measures were indexed to body size. Sex-specific multivariable linear regression analyses adjusting for confounders were performed to assess the associations of measures of arterial load with log LVMI and RWT. RESULTS None of the hemodynamic measures were associated with LVMI in either sex, or with RWT in men. However, in women, measures of aortic stiffness and early, pulsatile hemodynamic load were independently associated with increased RWT: β ± SE = 0.008±0.004 for Z _c; 0.003±0.001 for cfPWV, and -0.009±0.003 for PAC (P ≤ 0.05 for each). Female sex was a significant effect modifier of the associations of Z _c, cfPWV, and PAC with RWT (P ≤ 0.03 for each of the interaction terms). CONCLUSIONS Greater Z _c and cfPWV and lower PAC are independently associated with increased RWT in women but not in men. Our findings suggest that aortic stiffness and greater early, pulsatile hemodynamic load affect left ventricular concentric remodeling in a sex-specific manner.