ABSTRACT
EFFECTS OF HORMONE REPLACEMENT THERAPY ON SYSTEMIC ARTERIAL PROPERTIES IN POST-MENOPAUSAL WOMEN
Eric Alps Chen, B.S.
University of Pittsburgh, 2002
Vascular stiffness properties contribute significantly to the arterial system hydraulic load. There is evidence that vascular stiffness plays a role in cardiovascular remodeling and may be an independent cardiovascular risk factor. Menopause accelerates age-associated increase in arterial stiffness and estrogen administration, which has vasodilating properties, can potentially mitigate this post-menopausal increase in stiffness.
The present study examined the effects of chronic hormone replacement therapy (HRT) on systemic arterial mechanical properties in 35 post-menopausal women, divided into two groups: those receiving no HRT (Control, n = 25) and those receiving HRT (HRT-all, n = 10). The HRT-all group consisted of two subgroups: estrogen alone (HRT-E, n = 5) and a combination of estrogen and progesterone (HRT-EP, n = 5). Noninvasive data were collected serially at five times: once at the baseline during the first visit and during four subsequent visits after the initiation of the study at 19±1, 108±5, 193±4, and 388±8 days, respectively. Heart rate (HR), stroke volume (SV), and cardiac output (CO) did not change significantly in the control group throughout the study. This was also true for both HRT groups, except for a small decrease in HR at Visits 3 and 4 for the HRT-E group and an increase in CO at Visit 3 in the HRT-EP group. Mean arterial pressure decreased over time in control and both HRT groups, reaching statistical significance at later times (fifth visit). Systemic vascular resistance did not change significantly in control and both HRT groups. Global arterial compliance (AC) was unchanged for the control group but tended to increase in the HRT-all group, although no statistical significance was reached. In contrast, the subgroup analysis revealed that AC increased for the HRT-E subgroup, reaching statistical significance at the fifth visit. Similarly, significant decrements in pulse wave velocity (PWV), an index of regional vascular stiffness, were observed only for the HRT-E group.
In conclusion, AC increased (vascular stiffness decreased) in subjects receiving chronic estrogen therapy only. The inclusion of progesterone seems to counteract the estrogen-mediated decrease in vascular stiffness, indicating that the vascular stiffness-associated cardio-protective effects of HRT, if any, may be limited to estrogen administration alone.
| Identifer | oai:union.ndltd.org:PITT/oai:PITTETD:etd-08192002-104306 |
| Date | 09 September 2002 |
| Creators | Chen, Eric Alps |
| Contributors | Dr. Sanjeev Shroff, Dr. Kirk Conrad, Dr. Harvey Borovetz |
| Publisher | University of Pittsburgh |
| Source Sets | University of Pittsburgh |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.library.pitt.edu:80/ETD/available/etd-08192002-104306/ |
| Rights | unrestricted, I hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to University of Pittsburgh or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report. |
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