Keywords: coronary heart disease secondary prevention of hormone replacement therapy
A large-scale clinical trials have shown that estrogen / progestin replacement therapy does not improve prognosis of coronary heart disease in women after menopause.
Hormone replacement therapy proposed
Very low incidence of coronary heart disease in women before menopause, significantly lower than men of the same age, the incidence rate was gradually increased after menopause, about to 75 to 80 years old, getting close to the men. The incidence of coronary heart disease in the gender differences, people consider sex hormones, therefore, the proposed application of hormones (estrogen and progesterone) replacement therapy to postmenopausal women.
Estrogen can regulate lipoprotein metabolism and improve endothelial function, and thus, in theory, it can prevent or mitigate the adverse trend of cardiovascular disease in postmenopausal women. In addition, hormone replacement therapy for menopausal syndrome symptoms such as hot flashes, sweating, irritability significant improvement, and the prevention of post-menopausal osteoporosis. Other components of hormone replacement therapy for progesterone, it can fight the increase in estrogen-induced uterine cancer, but also weaken the beneficial effects of estrogen on lipoprotein metabolism and endothelial function improved.
The meta-analysis showed that women receiving estrogen therapy at any given time, the therapy is a 50% reduction in the risk of coronary heart disease as a whole. The results show 30 postmenopausal women estrogen replacement therapy, hormone replacement therapy in coronary heart disease incidence can be decreased by 44%, reduced the incidence of angiographic proof coronary occlusion, but no significant downward trend of the incidence of stroke. Since these observational studies is selection bias may overestimate the protective effect of hormone replacement therapy on coronary heart disease.
The HERS results of shaken hormone replacement therapy
First maximum of a hormone replacement therapy for postmenopausal women with coronary heart disease secondary prevention randomized double-blind controlled prospective study of the HERS (Heart and Estrogen / Progestin is Replacement Study), 2763 cases of postmenopausal patients with coronary heart disease (mean age 66.7 years) randomly divided into hormone replacement and placebo groups, respectively, taking equine estrogen plus medroxyprogesterone acetate or placebo, with an average follow-up of 4.1 years. The HERS results of 1998 made public: the incidence of non-fatal myocardial infarction and coronary heart disease mortality of patients with no difference between the hormone replacement group and the placebo group, although the hormone replacement group than in the placebo group low-density lipoprotein protein cholesterol (LDL-C), low levels of 11%, high level of high-density lipoprotein cholesterol (HDL-C) 10% (P <0.001). Detailed data analysis shows that the initial 1, the hormone replacement group 50% increased risk of coronary heart disease, reduce the risk of coronary heart disease in the 4 to 5 years. At present, the reason for this phenomenon is unclear. Observation process, the hormone replacement group venous thromboembolism compared with the placebo group (34 versus 12, P = 0.002) and cholelithiasis (84 of 62), a high incidence of cancer incidence, fractures and total mortality rate had no effect . (JAMA 1998; 280:605)
Various interpretations and assumptions to pour
The HERS results of a cause of shock, many people questioned or speculate. Herrington proposed two hypotheses, estrogen plus progestin on cardiovascular disease prevention may be invalid; opposite effect of early and late drug. There have been several reports show that estrogen alone and estrogen with progestin combination, no difference in the impact of CHD risk have no effect, so that the protective effect of estrogen on the heart, not the progesterone antagonism. cause. Interpretation of the researchers of the second hypothesis, there is a small group of women susceptible populations, they are prone to hormone replacement therapy, coronary heart disease, these people accept that the onset of this therapy early. Heckbert et al reported the results early hormone replacement therapy increases the risk of myocardial infarction, the estrogen application deadline to the risk of myocardial infarction negative, consistent with the HERS findings. Ong that the HERS in patients with early thrombosis tends to increase the incidence of myocardial infarction, should further study the interaction between coagulation factors and hormone replacement therapy.
Sellivan that young women due to menstrual blood loss, loss of iron, to avoid the onset of myocardial infarction, the so-called “iron hypothesis". Hormone replacement therapy late due to uterine bleeding, resulting in storage iron level was significantly decreased, thereby reducing the risk of coronary heart disease. Recommended monitoring of serum ferritin levels in the use of hormone replacement therapy. Some studies have indicated that the iron and atherosclerosis may be relevant. It is worthwhile to explore the problem from another angle. Selective estrogen receptor modifiers trials observable data is not yet people hold too high hopes. Whether raloxifene trials are underway to reduce coronary heart disease events.
Postmenopausal women with dyslipidemia, application statins reduce the risk of coronary heart disease. Secondary prevention in patients with coronary heart disease in postmenopausal prefer lipid regulating agents, such as beta-blockers safe and reliable method of hormone replacement therapy should be cautious.