Background and objectives: The incidence of coronary artery disease (CAD) is higher in post-menopausal than in pre-menopausal women. Epidemiological studies suggest that hormone replacement therapy (HRT) decreases the risk of cardiovascular disease in post-menopausal women. HRT could modify the cardiovascular risk via several mechanisms, including modifications in the fibrinolytic system and lipoprotein (a) levels. Our study was aimed at investigating some of these modifications.
Design and methods: In the cross-sectional part of the study we evaluated several components of the fibrinolytic system, coagulation inhibitors and lipid profile in premenopausal (n=15) and post-menopausal women (n=64) with CAD and compared these parameters with those of healthy pre-menopausal (n=31) and post-menopausal women (n=88). The prospective part of the study analyzed the effect of HRT with transdermal estrogen with or without progestogen in post-menopausal women with CAD.
Results: Pre- and postmenopausal women with CAD showed significant lower fibrinolytic activity and higher plasminogen activator inhibitor type 1 (PAI-1) levels than their control groups. Lp(a) levels were higher in premenopausal women with CAD than in healthy premenopausal women. In post-menopausal women with CAD, HRT induced a significant decrease in PAI-1 and Lp(a) levels. No significant differences were observed in any parameter studied between the groups treated with transdermal estrogen with and without progestogen.
Interpretation and conclusions: CAD is associated with a decrease in fibrinolytic activity, possibly due to an increase in PAI-1 levels. An increase in fibrinolytic activity and a decrease in PAI-1 and Lp(a) levels were observed in CAD women receiving transdermal HRT and these changes may have a favorable impact on the risk of new cardiovascular events in post-menopausal CAD women.