Women exhibit a greater age-related increase in proximal aortic stiffness than men

Background Large artery mechanical properties are a major determinant of pu lse pressure and cardiovascular outcome. Sex differences in these propertie s may underlie the variation in cardiovascular risk profile between men and women, in relation to age. Objective To investigate sex differences in the age-related stiffening of l arge arteries. Design Cross-sectional. Methods One hundred and twenty healthy men and women were recruited and div ided equally into tertiles by age: young (mean +/- SD, 23 +/- 5 years), mid dle-age (47 +/- 3 years) and older (62 +/- 7 years). Lipids, mean arterial pressure and heart rate were matched within each tertile. Carotid tonometry and Doppler velocimetry were used to measure indices of large artery stiff ness. Results There was no sex difference in systemic arterial compliance (SAC) i n the young group (mean +/- SEM. 0.61 +/- 0.05 arbitrary compliance units ( ACU) in women compared with 0.67 +/- 0.04 ACU in men), but in the older pop ulation women had lower SAC than men (0.27 +/- 0.03 ACU compared with 0.57 +/- 0.04 ACU respectively; P < 0.001). Measures independent of aortic geome try (distensibility index and aortic impedance) indicated that stiffness wa s lower in young women than in men (P < 0.05), but the reverse was true in the older population (P < 0.01). This paralleled the brachial and carotid p ulse pressures, which were lower in young (P < 0.01) and higher in older wo men compared with those in men (P < 0.05). Follicle stimulating hormone con centrations correlated strongly (r values 0.39-0.65) with all indices of ce ntral, but not peripheral, arterial function, whereas concentrations of lut einizing hormone, progesterone and oestradiol correlated less strongly. Conclusions In men and women matched for mean pressures, the age-related st iffening of large arteries is more pronounced in women, which is consistent with changes in female hormonal status. J Hypertens 19:2205-2212 (C) 2001 Lippincott Williams & Wilkins.