Postmenopausal Hormone Replacement Therapy and Cardiovascular Disease

26 Jun
2010

Cardiovascular DiseaseINTRODUCTION

Historically, heart disease has been viewed as a health problem of middle-aged men, and misperceptions concerning the prevalence of cardiovascular disease among women still exist. However, cardiovascular disease is a significant health problem among women. The incidence of cardiovascular disease in men and women equalizes after the age of 65, and the prevalence among women exceeds that of men after the age of 75. Overall, coronary heart disease (CHD) and stroke are the leading causes of death among American women, accounting for 44.6% of all deaths in women. This figure is higher than the next four causes of female deaths combined. Also, women are more likely to die within one year following a heart attack than are men. Despite these facts, it has been reported that women are expressing more concern about than about cardiovascular disease. In reality, one of every two women will die from heart disease or stroke, whereas only one of 25 will die from breast cancer.

As a result of this high incidence, researchers are looking for interventions to decrease the morbidity and mortality associated with cardiovascular disease among women. The observation that estrogen deficiency following natural or surgically induced menopause is associated with two to three times the risk of cardiovascular disease has led researchers to investigate the use of HRT in postmenopausal women for the prevention of CHD. This paper evaluates the evidence concerning the use of HRT for this indication.

MENOPAUSE AND CARDIOVASCULAR DISEASE

The relationship between menopause and cardiovascular disease has been studied in order to determine the postmenopausal physiological changes that might contribute to this disorder. Several alterations have been noted. There is evidence that levels of total cholesterol, low-density lipoprotein (LDL)-cholesterol, and triglycerides increase after menopause while high-density lipoprotein (HDL)-cholesterol levels decline. These unfavorable changes in the plasma lipoproteins increase the risk of atherosclerosis and subsequent heart disease.

It has also been discovered that non-lipoprotein effects contribute to the development of postmenopausal CHD. For instance, decreased insulin production and insulin-receptor sensitivity have been observed in postmenopausal women. The resulting disturbance of carbohydrate metabolism is a major risk factor for CHD. canadian pharmacy viagra

Menopause is also associated with a significant increase in the central deposition of body fat, resulting in an increased waist circumference. This pattern of body fat deposition is associated with higher triglycerides, lower HDL-cholesterol, and greater insulin resistance, all of which increase CHD risk.

It has also been hypothesized that estrogen acts directly on the vascular endothelium, resulting in increased nitric oxide and prostacyclin production and subsequent vasodilation with en-dothelial healing. After menopause, these protective effects are lost and increased vasoconstriction, vasospasm, and angina often ensue. Other mechanisms that have been investigated but that are not as well understood include estrogen’s effects on coagulation and fibrinolytic balance.

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