The American Heart Association (AHA) has issued a statement for health care professionals on cardiovascular disease in women. According to the AHA, there are still misperceptions that cardiovascular disease is not a real problem for women, even though nearly 50 percent of women die of heart disease or stroke. The scientific statement appears in the October 1997 issue of Circulation.
The AHA states that cardiovascular disease, particularly coronary heart disease and stroke, remains the leading cause of death among women in America and, in 1994, accounted for 45.2 percent of all deaths in women. As the population ages, significantly more women will be at increased risk for morbidity and mortality associated with cardiovascular disease.
The AHA believes that health care systems need to shift paradigms to emphasize healthy lifestyles for young women to help prevent the development of risk factors for cardiovascular disease. The AHA report discusses recent advances in knowledge of the occurrence, determinants, risk factors, diagnosis, prevention and treatment of atherosclerotic cardiovascular disease in women, including coronary heart disease, hypertension, stroke and peripheral arterial disease.
Coronary Heart Disease
Studies show that coronary heart disease in women is largely preventable. The major risk factors for coronary heart disease in women are cigarette smoking, hypertension (including isolated systolic hypertension, especially in elderly women), dyslipidemia, diabetes, obesity, sedentary lifestyle and poor nutrition. Cigarette smoking remains the leading preventable cause of heart disease in women, and more than 50 percent of myocardial infarctions in middle-aged women can be attributed to smoking. The report suggests that pharmacologic intervention, including anti-platelet therapy and postmenopausal hormone replacement therapy, may be appropriate in selected patients. The value of aspirin and antioxidant vitamin supplements in women has not been determined.
The AHA recommends that a major emphasis be placed on lifestyle modifications for women, including smoking cessation, regular physical activity, maintenance of healthy weight and consumption of a diet low in saturated fat and high in fruits and vegetables. Further studies are recommended to determine the potential benefits of stress reduction and psychosocial intervention in the prevention of coronary heart disease in women.
The diagnosis of heart disease is more difficult in women than it is in men. Reports from the Framingham heart study showed that chest pain was not of great prognostic value in women. Women with classical angina pectoris had a 71 percent probability of angiographic evidence of disease, compared with 36 percent of women with probable angina. Nonspecific chest pain syndromes in women are rarely associated with significant disease on arteriography.
According to the AHA, chest pain remains the most common initial manifestation of coronary heart disease in women. It is possible to stratify patients into categories of low, intermediate and high likelihood of disease on the basis of the existence of minor and major determinants of heart disease to make diagnostic testing more cost-efficient and informative.
Gender-specific considerations related to diagnostic test performance may influence the choice of procedures used to evaluate chest pain syndromes in women. Data on results of exercise treadmill testing, myocardial perfusion imaging with thallium 201, radionuclide ventriculography and exercise echocardiography suggest that gender has a significant impact on the accuracy of widely available diagnostic tests and should be a consideration in the choice and interpretation of noninvasive tests. New techniques that hold promise, including electron beam computed tomography and three-dimensional imaging with magnetic resonance or positron emission tomography, are still considered experimental.
Stroke is the third leading cause of death in the United States and the leading cause of disability. The report notes that almost 4 million stroke survivors are alive today, and 52 percent of these are women. Stroke survivors are at greater risk of dementia and disability than persons without a history of stroke. Age and ethnicity are important predictors of survival among stroke victims. The rate of mortality associated with stroke is higher in blacks than it is in whites.
Many identifiable risk factors for ischemic stroke in both men and women have been fairly consistent over epidemiologic studies. These include hypertension, smoking, diabetes, ischemic heart disease, atrial fibrillation and transient ischemic attacks. Other risk factors may be involved, including hematologic factors, including hematocrit and white blood cell counts, infections and inflammations, psychosocial factors and lifestyle.
Treatment and acute interventions appear to be the same for men and women. In all stroke victims, early detection and treatment are vital. Thrombolytic therapy with recombinant tissue plasminogen activator for acute ischemic stroke can be effective when administered early in the course of the event. Women who have symptomatic carotid stenosis of 70 to 99 percent may benefit from the combination of carotid endarterectomy and aspirin therapy.
Peripheral Artery Disease
The AHA report lists smoking as the most consistently associated risk factor for peripheral artery disease, and prevalence rates in nonsmokers are less than one half of the rates in smokers. Other risk factors include glucose intolerance, increased body mass index, elevated blood pressure and elevated fibrinogen levels. The association between peripheral artery disease and lipid levels is not as clear. Peripheral artery disease itself is a strong risk factor for other cardiovascular events and mortality. According to the AHA, there is a threefold to fourfold increase in relative risk for all-cause mortality associated with peripheral arterial disease that is the same in both sexes.
Smoking cessation is recommended by the AHA for any patient diagnosed with peripheral artery disease. Antiplatelet therapy may be effective in some patients, and surgery is indicated in cases of severe disease, although a comprehensive program of atherosclerotic risk reduction and exercise is also necessary. Even though the role of lipid levels in the development of peripheral artery disease is unclear, lipid-lowering therapy is recommended by the AHA.
Hormones and Cardiovascular Disease
The AHA report also discusses the association of hormones and cardiovascular disease, including oral contraceptives and postmenopausal estrogen therapy. Overall, the report notes that the risk-benefit ratio for oral contraceptives is excellent except in women who smoke. The potential benefits and risks of postmenopausal estrogen therapy still need to be confirmed in randomized controlled clinical trials. Until these data are available, the AHA recommends that physicians individualize therapy based on a woman's baseline risk for cardiovascular disease and weigh the potential net benefit on overall health.
In conclusion, the AHA suggests that health care professionals be more sensitive to gender differences in presentation, prognosis and responsiveness to treatment of cardiovascular disease. More research in minority women is of particular importance. Health educators have an important role in communicating and interpreting scientific developments concerning heart disease in women.