Abstract # 85:

Scheduled for Friday, June 22, 2007 10:30 AM-10:45 AM: Session 8 (North Main Hall C/D) Symposium

Stage of Reproductive Life, Atherosclerosis Progression and Estrogen Effects on Coronary Artery Atherosclerosis

T. B. Clarkson
Wake Forest University School of Medicine, Comparative Medicine Clinical Research Center, Medical Center Boulevard, Winston-Salem, North Carolina 27157-1040, USA
     Today, there is controversy and confusion concerning whether postmenopausal hormone replacement therapy has any beneficial effects in inhibiting the progression of coronary artery atherosclerosis. The uncertainty has arisen because a large body of evidence had suggested that estrogen deficiency was the major modulator of atherosclerosis progression of females; however, recent clinical trials done using older postmenopausal women found no evidence of benefit and, indeed, harm during the first year of hormone treatment. Based largely on monkey studies, there is now an emerging hypothesis that the stage of reproductive life and the extent of atherosclerosis progression are primary determinants of whether estrogens will have cardiovascular benefits. In summary, monkey studies have found that the extent of premenopausal atherosclerosis (largely determined by psychosocial stress) determines the trajectory of progression and the subsequent extent of postmenopausal atherosclerosis (Clarkson & Appt, 2005). Additionally, the monkey studies have shown that there is a "window of opportunity" for estrogens to have their beneficial effects on arteries. When estrogens are administered just after surgical menopause, there is a 70% inhibition in the progression of coronary artery atherosclerosis; however, if estrogen treatment is delayed for a period equivalent to six postmenopausal years for women, there are no cardiovascular benefits.