Background: Whether the blunted nocturnal blood pressure (BP) fall alters the potential beneficial effects of estrogen replacement therapy (ERT) on arterial elastic properties in hypertensive postmenopausal women has not been clarified. The aim of this study was to determine the potential beneficial effects of ERT on arterial elastic properties and to investigate whether a blunted nocturnal BP fall could unfavorably modify the estrogen-induced alterations of large-artery stiffness in postmenopausal women with untreated essential hypertension.
Methods: A total of 66 postmenopausal women with untreated essential hypertension underwent carotid-femoral pulse wave velocity (PWV) measurements at baseline and after 12 weeks of ERT with 0.625 mg conjugated estrogen. By 24-h ambulatory BP monitoring, women were classified according to dipping status (nondippers, n = 21; dippers, n = 45).
Results: The two groups were similar regarding age, body mass index, time since menopause, and lipidemic profile. Initially, nondippers compared to dippers, although they had significantly greater office systolic BP (SBP), 24-h SBP, daytime SBP and night-time SBP (by 5, 2, 3, and 19 mm Hg, respectively, P < .05 for all cases), did not differ regarding left ventricular (LV) mass index and aortic PWV (116 v 114 g/m2 and 8.40 v 7.95 cm/sec, respectively, P = NS for both cases). Use of ERT, without affecting the office SBP and DBP, reduced significantly the aortic PWV in both nondippers and dippers (by 1.28 and 1.50 cm/sec, respectively, P < .05 for both cases). However, these PWV reductions were not different between the two groups (P = NS). A multivariate analysis identified patient age and 24-h SBP as significant determinants of estrogen-induced aortic PWV reduction (P < .05).
Conclusions: A blunted nocturnal BP fall does not attenuate the estrogen-induced favorable modifications of large artery elastic properties in hypertensive postmenopausal women. Whether these findings suggest that hypertensive women with ERT-induced attenuation of PWV represent a specific clinical subgroup of patients with possible ERT-associated cardiovascular benefit remains to be determined by properly randomized trials.