Cerebrovascular reactivity after cessation of menopausal hormone treatment

Abstract

Objective: Women who are currently using menopausal hormone therapy (MHT) have higher cerebrovascular reactivity when compared with postmenopausal women who are not taking MHT; however the effect of cessation of MHT on cerebrovascular reactivity is not known. Given that MHT can have structural and activational effects on vascular function, this study was performed to characterize cerebrovascular reactivity following cessation of MHT in women at low risk for cerebrovascular disease.Methods: Cerebrovascular reactivity measured in a subset of women from the Kronos Early Estrogen Prevention Study (KEEPS) three years after the cessation of the study drug [oral conjugated equine estrogen (oCEE); transdermal 17-β estradiol (tE2); or placebo (PLA)].Results: Age, body mass index, and blood pressure were comparable among groups. At rest, middle cerebral artery velocity (MCAv), cerebrovascular conductance index (CVCi), mean arterial pressure (MAP) and cerebral pulsatility index did not differ among groups. Slope-based summary measures of cerebrovascular reactivity did not differ significantly among groups. However, utilizing repeated measures modeling, there was a significant upward shift in MCAv responses (p=0.029) in the combined MHT group compared with PLA group. Conclusion:MHT has a marginal sustained effect on cerebrovascular reactivity when measured three years after cessation of hormone treatment.

Integrative cardiovascular control in women: Regulation of blood pressure, body temperature, and cerebrovascular responsiveness

“…Additionally, repeated measures analysis revealed a marginal sustained effect of higher cerebral artery blood velocity during hypercapnia and a trend for greater cerebrovascular reactivity in the combined hormone group. 69 Importantly, these data are the first to report on the potential sustained effects of long-term menopausal HRT 3 years after cessation of treatment. While menopausal HRT use in postmenopausal women is associated with elevated cerebrovascular reactivity, comparable to values in premenopausal women, 60 the effect is only marginal in the years after cessation of menopausal HRT.…”

“…67 Three years after cessation of hormone or placebo treatment, there were no significant group differences in aortic hemodynamics 68 or cerebrovascular reactivity. 69 However, there was a trend for higher cerebral artery blood velocity and cerebrovascular conductance at rest, which could reflect higher global cerebral blood flow in the combined menopausal hormone groups (oral conjugated equine estrogen and transdermal 17ß-estradiol). Additionally, repeated measures analysis revealed a marginal sustained effect of higher cerebral artery blood velocity during hypercapnia and a trend for greater cerebrovascular reactivity in the combined hormone group.…”