Comparative effects of aging in men and women on the properties of the arterial tree

OBJECTIVES We measured the properties of the arterial tree, seeking differences between men and women as they aged. BACKGROUND There are many differences between men and women, besides menopause, which might account for such disparities. These include body height, heart rate, stroke volume and smaller arterial diameters. Any gender differences in arterial stiffness could influence pulse pressure (PP), now recognized as a cardiovascular risk factor. METHODS A total of 530 patients (347 men and 183 women) were classified by age into quartiles: ≤40, 41–47, 48–54 and ≥55 years. The middle groups represented the menopausal years. Studies included brachial artery blood pressure (BP), aortic pulse wave velocity (PWV), B-mode ultrasonography and wave form analysis of the common carotid artery (CCA), with its conversion to the aortic wave form. Standard echocardiography provided left ventricular dimensions and flows. Calculated values included CCA compliance and distensibility, systemic compliance, stroke volume and peripheral resistance. RESULTS At all ages, women had higher heart rates but lower BP than men. Pulse pressure, however, was lower in young women and higher in older women. Measurements influenced by body size, such as CCA diameter, compliance and systemic compliance, were lower in women. Those related to arterial wall properties, such as CCA and aortic distensibility, were the same. Although aortic PWV rose similarly with aging, PWV had more of an influence on PP in women than did mean BP. The reverse was true in men. CONCLUSIONS Despite lower mean BP and similar arterial distensibility, women develop a higher degree of pulsatility with aging, as compared with men. This is mainly due to their smaller physical characteristics, independent of the role of menopause and its related hormonal changes.