INFLUENCE OF SEX ON ARTERIAL HEMODYNAMICS AND BLOOD-PRESSURE - ROLE OF BODY HEIGHT

Systolic pressure is lower in premenopausal women than in age-matched men, but underlying alterations are not well characterized. Aging and body size alter arterial function, influencing pressure wave propagation and amplification in peripheral and central arteries. To assess the possibility that systolic pressure differences in women are related to smaller body size, we studied arterial function in 119 men and 104 women. Premenopausal and postmenopausal women were compared with age-matched men. The following parameters were measured: ankle-arm pressure index (Doppler), aortic and arterial distensibility (pulse wave velocity), systolic pressure and the effect and time delay of arterial wave reflections in the common carotid artery (applanation tonometry), and diameters of the abdominal aorta and aortic bifurcation and their ratio (aortic tapering, echography). Premenopausal women had lower brachial (P<.05) and ankle (P<.01) systolic pressures than age-matched men, whereas the ankle-arm pressure index was higher in men (P<.01). In the overall population the ankle-arm index was positively correlated with body height (P<.001). Carotid systolic pressure was similar in women and men, with an increased effect and earlier return of wave reflections in women (P<.01). The effect of wave reflections was inversely correlated with body height (P<.001) and positively associated with aortic tapering (P<.001), which was increased in women (P<.01). In premenopausal women the distensibility of brachial and femoral arteries was higher than in age-matched men (P<.01), whereas aortic distensibility was not different. Postmenopausal women had arterial distensibility similar to that of age-matched men but still had an increased effect of wave reflections. This study shows that body height is positively correlated with systolic pressure amplification from central to peripheral arteries and inversely correlated with the effect of wave reflections in central arteries. Shorter body height in women results in less peripheral systolic pressure amplification, with lower peripheral but not central systolic pressure. Greater arterial distensibility in premenopausal women partially offsets the effects of shorter body height. After menopause, arterial distensibility is similar to that of age-matched men and does not compensate for smaller body size, resulting in a persisting increased effect of wave reflections in central arteries.