The risk factors for coronary artery disease are presented in Table 9.2. Central to treating cardiovascular disease is the control of contributing diseases and risk factors through lifestyle modifications (Table 9.3). Aerobic exercise protects against cardiovascular disease (14). Additional aspects of prevention of myocardial disease, renal disease, and stroke include control of hypertension, identification and control of diabetes and obesity, and control of dietary fats, especially cholesterol, in susceptible individuals (Fig. 9.1). The presence or absence of target organ damage shown in Table 9.4 also determines the risk of coronary artery disease in hypertensive patients.
Hypertension The relationship between hypertension and cardiovascular events such as stroke, coronary artery disease, congestive heart disease, and renal disease is well known. More than 50 million people in the United States have hypertension. It is found in 15% of the population between the ages of 18 and 74 years; the incidence increases with age and varies with race. The contribution of hypertension to overall cardiovascular morbidity and mortality in women was
Table 9.3 Lifestyle Adjustments to Manage Hypertension
Weight reduction to maintain a body mass index of 18.5–24.9
Limit alcohol use to 2 drinks per day for men (24 oz beer, 10 oz of wine, 3 oz of 80-proof whiskey) and no more than 1 drink per day in women and lighter-weight persons
Regular aerobic exercise (at least 30 minutes per day of brisk walking most days of the week) Decrease salt intake to less than 2.4 g of sodium or6gof sodium chloride per day
Consume a diet rich in fruits, vegetables, and low-fat dairy products with a reduced content of saturated and total fat
Adapted from Chobanian AV, Bakris GL, Black HR, et al. The seventh report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC VII). JAMA 2003;289:2560–2572.
Figure 9.1 Disease and risk factors contributing to cardiovascular disease.
thought to be less important than that in men, but this may reﬂect the relative absence of research in women (15). After age 50, women have a higher incidence of hypertension than men; this may be a confounding variable related to the overall mortality of men at an earlier age (16). More than 60% of those individuals older than age 60 years can be classified as hypertensive (17). Recognition and treatment of hypertension may decrease the development of renal and cardiac disease.
Epidemiology The incidence of hypertension is twice as high in African Americans than in whites. Geographic variations exist: the southeastern United States has a higher prevalence of hypertension and stroke, regardless of race (16). One multi-institutional study confirmed an increased incidence of hypertension in African Americans, and that the incidence is increased in individuals with lower levels of education (17). Preventive measures can be most effective in those at highest risk, such as in African American women and individuals from the lowest socioeconomic level (17). The inﬂuence of genetic predisposition is poorly understood. Studies of women are limited to those that determine side effects of medication and the impact of certain medications on long-term lipid status (13).
Classically, hypertension is defined as blood pressure levels higher than 140/90 when measured on two separate occasions. Medication may be indicated only for individuals at high risk. Individuals at low risk, such as white women with no other risk factors, may benefit from lifestyle modification alone. Life insurance risk tables indicate that when blood pressure is controlled to lower than 140/90, normal survival occurs over a 10-to 20-year follow-up, regardless of gender. Current recommendations are based on sustained blood pressures higher than 140/90 (18).
Table 9.4 Target Organ Damage