Epidemiological data on heart disease, stroke, and associated risk factors are compiled and published annually in the Heart Disease and Stroke Statistical Update. This publication is a collaborative effort of the American Heart Association (AHA), the Centers for Disease Control and Prevention, the National Institutes of Health, and other government agencies. This chapter draws from the most recent edition of the report, the Heart Disease and Stroke Statistics 2011 Update, in addition to other resources to provide an overview of the burden of cardiovascular diseases in the United States.
The AHA reports that approximately 82.6 million people in the United States currently have one or more forms of cardiovascular disease (CVD), making it a leading cause of death for both men and women (Roger et al., 2010). Common types of cardiovascular disease include coronary heart disease (CHD), stroke, hypertension, and congestive heart failure. Other forms of CVD are atrial and ventricular arrhythmias, congenital cardiovascular disorders, rheumatic heart disease, peripheral artery disease, and other conditions affecting the circulatory system, such as deep vein thrombosis and pulmonary embolism.
Coronary Heart Disease
An estimated 16.3 million Americans aged 20 and older have CHD, a prevalence of 7 percent. The prevalence for men is 8.3 percent and for women is 6.1 percent. Non-Hispanic white men have the highest prevalence of CHD at 8.5 percent, followed by non-Hispanic black men at 7.9 percent and Mexican American men at 6.3 percent. For women, non-Hispanic black women have the highest rate of CHD at 7.6 percent, followed by non-Hispanic white women at 5.8 percent and Mexican American women at 5.6 percent (Roger et al., 2010). Data from the Strong Heart Study, funded by the National Heart, Lung, and Blood Institute (NHLBI), found that the incidence of CHD in American Indians between the ages of 45 and 74 was 17.9 per 1,000 person-years: 23.2 per 1,000 person-years in men and 14.8 in women (Lee et al., 2006).
CHD includes heart attacks (myocardial infarction) and angina pectoris (chest pain). In the U.S. population, 7.9 million individuals have suffered heart attacks and 9 million have experienced angina pectoris. Data from Roger and colleagues (2010) show that the overall prevalence for myocardial infarction in American adults aged 20 and
older is 3.1 percent. Men are more likely than women to have had a heart attack. The prevalence among non-Hispanic white men and non-Hispanic black men is the same (4.3 percent), while Mexican American men are less likely to have had a heart attack (3 percent). Both non-Hispanic white women and non-Hispanic black women experience higher rates of heart attack (2.1 and 2.2 percent, respectively) than do Mexican American women at 1.1 percent. Data from the 2009 Behavioral Risk Factor Surveillance System (BRFSS) show the highest prevalence of heart attack is in West Virginia (6.5 percent) and Kentucky (5.9 percent). The lowest rate (1.9 percent) was reported in the District of Columbia. West Virginia also had the highest prevalence of angina or coronary heart disease, while the District of Columbia had the lowest (Roger et al., 2010).
About 7 million Americans aged 20 or older have had a stroke. Each year approximately 610,000 experience their first stroke and another 185,000 experience a recurrence (AHA, 2009). Approximately 87 percent of all strokes are ischemic; 10 percent result from intracerebral hemorrhage and 3 percent result from subarachnoid hemorrhage.
Approximately 2.7 percent of men and 2.5 percent of women aged 18 or older have a history of stroke. According to the 2009 BRFSS, the states with the highest prevalence of stroke were Alabama and Oklahoma, and the lowest was Colorado (Roger et al., 2010). NHLBI reports that blacks have nearly twice the risk of first-time stroke when compared with whites. The age-adjusted stroke incidence rates at ages 45–84 are 6.6 per 1,000 persons in black males, 3.6 in white males, 4.9 in black females, and 2.3 in white females (NHLBI, 2006).
Data from the Strong Heart Study found that incidence of stroke was 6.8 per 1,000 persons (age- and sex-adjusted) in American Indians (Zhang et al., 2008). Data from the 2005 BRFSS also showed that the prevalence of stroke was higher among American Indians/Alaskan Natives and multiracial persons than among whites. Increased incidence of stroke has been reported among Mexican Americans when compared with non-Hispanic whites. Stroke symptoms are more commonly reported among individuals with fair to poor perceived health status and those with lower income and educational attainment: approximately twice the proportion of those with less than 12 years of education reported a history of stroke compared with college graduates (HHS, 2006).
Approximately 76.4 million—one in three—American adults have high blood pressure (hypertension), defined as an elevated pressure of 140 mmHg systolic or higher and/or 90 mmHg diastolic or higher, use of antihypertensive medication, or being told at least twice by a physician or other health professional that one has high blood pressure. National Health and Nutrition Examination Survey (NHANES) data collected between 2003 and 2006 reveal that among adults with hypertension, 78 percent were aware of their condition and 68 percent were using antihypertensive medication; however, less than 64 percent of those receiving treatment had their condition controlled (Roger et al., 2010).
The prevalence of hypertension increases with age. About half of individuals between the ages of 60 and 69, and three quarters of individuals over the age of 70, have hypertension. Framingham Heart Study investigators found the lifetime risk of hypertension to be approximately 90 percent for men and women who had normal blood pressure at age 55 or 65 and survived to ages 80–85. More men than women have hypertension before age 45, similar proportions of men and women experience hypertension between the ages of 55 and 64, and women are more likely to have hypertension later in life (NCHS, 2007). U.S. blacks have the highest prevalence of hypertension in the world. They develop the disease earlier in life, have much higher average blood pressures than whites do, and as a result have greater rates of nonfatal and fatal stroke, heart disease deaths, and end-stage kidney disease. The prevalence of hypertension increased among blacks and whites in the United States between 1999 and 2002, rising from 35.8 to 41.4 percent among blacks and from 24.3 to 28.1 percent among whites (Roger et al., 2010). Factors such as birth outside of the United States, speaking a language other than English at home, and fewer years spent living in this country are associated with lower rates of hypertension (Moran et al., 2007).
Recent data show that approximately 5.7 million Americans have congestive heart failure. The majority of individuals with heart failure have antecedent hypertension, and those with a blood pressure of 160/90 mmHg or greater have twice the lifetime risk of heart failure compared with those whose blood pressure is less than 140/90 mmHg (Roger et al., 2010). Recent studies have reported improved survival from heart failure, although incidence has not declined in the past 20 years (Barker et al., 2006). Heart failure before age 50 is more prevalent among blacks than whites. Incidence rates (age-adjusted, per 1,000 person years) from the NHLBI-funded Atherosclerosis Risk In Community (ARIC) study were 3.4 for white women, 6 for white men, 8.1 for black women, and 9.1 for black men.
Cardiovascular diseases claimed 813,804 lives in 2007. On average, more than 2,200 Americans lose their lives to cardiovascular disease each day. Cardiovascular diseases are consistently ranked as the leading cause of death in the United States, exceeding all forms of cancer. The overall mortality rate (per 100,000) due to cardiovascular diseases was 251.2 in 2007; the rate for men was 300.3, and for women it was 211.6. More than 150,000 American deaths from cardiovascular disease in 2007 were persons under age 65; approximately one-third of cardiovascular deaths occurred before the age of 75. From 1997 to 2007, death rates from cardiovascular diseases declined 27.8 percent. Black individuals continue to experience substantially higher mortality rates than do other racial/ethnic groups (Roger et al., 2010). Table 2-1 presents data on mortality by gender and race/ethnicity.
Coronary Heart Disease
As the leading cause of death in America, CHD was responsible for 406,351 deaths, or one of every six, in 2007. Heart attacks were responsible for 132,968 deaths, and approximately 15 percent of those who have a heart attack will die from it, resulting in an average of 15 lost years of potential life. The annual incidence of sudden cardiac death is higher in men than women, but this difference begins to narrow with advancing age. Approximately 81 percent of individuals whose death is attributed to coronary heart disease are over age 65. Death rates from coronary heart disease decreased by 59 percent between 1950 and 1999, and decreased 26.3 percent between 1997 and 2007. CHD death rates vary by gender and race/ethnicity, as shown in Table 2-2.
|White||Black||Hispanic/Latino||American Indian/ Alaskan Native||Asian/Pacific Islander|
SOURCE: Adapted from Roger et al. (2010).
|White||Black||Hispanic/Latino||American Indian/ Alaskan Native||Asian/Pacific Islander|
SOURCE: Adapted from Roger et al. (2010).
Approximately 1 of every 18 deaths in the United States in 2007 was caused by stroke, resulting in 135,952 lives lost. It is also a leading cause of long-term disability. One American dies of a stroke about every 4 minutes. For individuals aged 45 through 64, 8 to 12 percent of ischemic strokes result in death within 30 days, and for hemorrhagic strokes the rate is 37–38 percent. The annual stroke death rate declined by 34.3 percent between 1997 and 2007, and the actual number of stroke deaths decreased by 18.8 percent. The 2007 death rate for stroke was 42.2 per 100,000. Table 2-3 provides data on stroke deaths by race/ethnicity.
More women than men die of stroke each year, with 60.6 percent of stroke deaths in 2007 occurring among women (Roger et al., 2010). Many states with high stroke mortality rates are concentrated in the southeast, which has become known as the “Stroke Belt” (HHS, 2006).
Hypertension claimed 57,732 lives in 2007. Between 1997 and 2007, the death rate from hypertension increased 9 percent and the actual number of deaths rose 35.6 percent. The overall death rate due to hypertension in 2007 was 17.8 per 100,000. However, there is tremendous disparity in the death rates for whites and blacks. The death rate for black males was 49.2, but only 15.7 for white males. Black females also suffer at much greater rates than white females—37 and 14.3, respectively.
Hypertension reduces life expectancy by 5.1 years for men and 4.9 years for women when compared with individuals of the same sex at age 50 who have normal blood pressure. Hypertension also increases mortality from heart disease and stroke; for every increase of 20 mmHg systolic and 10 mmHg diastolic, there is a doubling of mortality from these conditions (Roger et al., 2010).
In 2007, 277,193 deaths from heart failure were reported, including 121,684 among men and 155,509 among women. Heart failure commonly occurs as an end result of other cardiovascular diseases such as coronary heart disease and long-standing hypertension, and is noted on one of every nine death certificates. The overall death rate for heart failure was 85.4 per 100,000 in 2007. Black males have the highest death rate due to heart failure (104.2) followed by white males (99.2), black females (82.5), and white females (76.7). Although survival following the onset of heart failure has improved over time, about half of individuals die within 5 years of a heart failure diagnosis (Roger, et al., 2010).
The direct and indirect costs of cardiovascular diseases and stroke in the United States are estimated at more than $286 billion. This includes $167 billion in direct costs associated with physicians and other health professionals, hospital and nursing home services, medications, home health care, and medical durables as well as $119 billion in indirect costs resulting from lost productivity, illness, and death. The following estimated costs (direct and indirect) for various cardiovascular diseases in 2010 were reported by Roger and colleagues (2010):
|White||Black||Hispanic/Latino||American Indian/ Alaskan Native||Asian/Pacific Islander|
SOURCE: Adapted from Roger et al. (2010).
- Heart disease: $177.5 billion;
- Stroke: $40.9 billion;
- Hypertensive disease: $43.5 billion; and
- Other circulatory conditions: $24.6 billion.
Cardiovascular disease is multifactorial; some risk factors are modifiable, and some (age, heredity, and male sex) cannot be modified. Among the modifiable risk factors for cardiovascular disease is a diet that is high in saturated fat and sodium. Other risk factors are tobacco smoke, high blood cholesterol, high blood pressure, physical inactivity, obesity and overweight, and diabetes mellitus. Stress and excessive alcohol consumption may also contribute to cardiovascular disease risk. This risk is higher among Mexican Americans, American Indians, native Hawaiians, and some Asian Americans, in part because of the higher rates of obesity and diabetes in these populations.
Cigarette smoking resulted in an estimated 443,000 premature deaths between 2000 and 2004; 32.7 percent of these deaths were related to cardiovascular disease in adults over age 35. Smokers experience a risk of developing coronary heart disease that is two to four times greater than individuals who don’t smoke, and they have about twice the risk of stroke and 10 times the risk of peripheral vascular disease compared with nonsmokers. Secondhand smoke and smoking cigars or pipes can also increase the risk of heart disease (Roger et al., 2010). The Healthy People 2010 target for smoking (12 percent or less) was achieved by only two states.
Elevated total blood cholesterol increases the risk of coronary heart disease, particularly in the presence of other risk factors such as high blood pressure and smoking. A person’s cholesterol level is also affected by age, sex, heredity, and diet (AHA, 2010). NHANES data showed that from 2005 to 2008, approximately 33.5 million adults aged 20 and older had blood cholesterol levels ≥ 240 mg/dL. NHANES data from 1999–2006 showed that 8 percent of adults had undiagnosed hypercholesterolemia. Approximately one-third of individuals whose test results indicated high blood cholesterol or who were taking a cholesterol-lowering medication had not been notified by a health professional about their condition. Fewer than half of Mexican Americans with high cholesterol were aware of their condition, and blacks and Mexican Americans were less likely to be aware of their condition than were whites. Women were less likely than men to be aware that they had high cholesterol.
Physical inactivity is another risk factor for coronary heart disease. Moderate activity uses large muscle groups and is at least equivalent to brisk walking. Vigorous activity is rhythmic, repetitive physical activity that uses large muscle groups at 70 percent or more of the maximum heart rate for a person’s age (HHS, 2010). Regular, moderate-to-vigorous physical activity helps prevent CVD and can improve blood cholesterol, hypertension, diabetes, and obesity. Data from the 2009 National Health Interview Survey showed that one-third of adults did not engage in daily leisure-time physical activity (light to moderate physical activity for at least 10 minutes). Furthermore, those data demonstrated that:
- 56 percent of adults (60.1 percent of women and 50.3 percent of men) reported no vigorous activity;
- 61.7 percent of American Indians/Alaskan Natives, 61.6 percent of blacks, 54.1 percent of whites, 61.4 percent of Asians, and 69.9 percent of Hispanic/Latinos reported not engaging in vigorous activity;
- 77.6 percent of individuals with less than a high school education, 66.2 percent with a high school diploma, 54 percent with some college, and 39.3 percent of respondents with a bachelor’s degree or higher did not report engaging in any vigorous physical activity; and
- Fewer than half of adolescents (aged 14–17) met physical activity guideline recommendations of ≥ 60 minutes of moderate to vigorous activity on most days of the week.
Obesity is another risk factor for cardiovascular disease. Estimates from 2006 showed that about two-thirds of U.S. adults were overweight or obese; of these, more than a third—or 74 million—individuals were obese (AHA, 2009). Overweight for adults is defined as a body mass index (BMI) of 25 to 30, and obesity as a BMI of 30 or greater. Individuals who are obese or overweight are more likely to develop heart disease and stroke, even in the absence of other risk factors. Reducing weight by even 10 pounds can reduce the risk of cardiovascular disease (AHA, 2010). Overweight and obesity increase the risk of other CVD risk factors such as hypertension, hyperlipidemia, and diabetes. The age-adjusted relative risk for CVD is increased by about 20 percent in men and women who are overweight. Among those who are obese, the risk increases by 46 percent for men and 64 percent for women. NHANES data from 2003 to 2006 showed that nearly one-third of children and adolescents aged 2 to 19 years were at or above the 85th percentile of the 2000 BMI-for-age growth chart.
The World Health Organization (WHO) estimates that by 2015 the global burden of overweight will increase to 2.3 billion individuals, and obesity will increase to more than 700 million individuals. Obesity increases the risk of ischemic stroke in all racial and ethnic groups, and it was associated with 13 percent of all cardiovascular disease deaths in 2004. In addition to CVD, obesity is also associated with increased mortality due to some cancers, diabetes, and kidney disease. Furthermore, it can play a role in poor school performance, tobacco use, alcohol use, premature sexual behavior, and poor diet (Roger et al., 2010).
Diabetes, another risk factor, greatly increases the risk of cardiovascular disease, and approximately 75 percent of individuals with diabetes die from some form of cardiovascular disease (AHA, 2010). Adults with diabetes have heart disease death rates that are two to four times higher than rates in those without diabetes. NHANES data from 2005–2008 show that approximately 18 million adults had diabetes, 7 million had undiagnosed diabetes, and 81.5 million (37 percent of U.S. adults) had pre-diabetes (fasting blood glucose of 100 to < 126 mg/dL). American Indians have the highest prevalence of diabetes among all ethnic groups. Among the participants in the Strong Heart Study1 ages 45–74 years, 70 percent of those in Arizona had diabetes as did 40 percent of those in Oklahoma and North and South Dakota (Lee et al., 1995). Non-Hispanic blacks and Mexican Americans experience a disproportionately high prevalence of diabetes when compared with non-Hispanic whites (Roger et al., 2010). The prevalence of diabetes rose substantially in the 1990s, increasing by 61 percent from 1990 to 2001, and it is expected to more than double from 2005 to 2050 (from 5.6 to 12 percent) in all age, sex, and race/ethnicity groups (AHA, 2009).
National estimates of population changes in commonly accepted risk factors for CVD have, in general, demonstrated consistent improvements over the past several decades. However, increases in obesity and declining levels of physical activity are important exceptions to these trends. In an analysis published in the New England Journal of Medicine, Ford and colleagues (2007) reported that approximately half the decline in deaths from coronary heart disease among U.S. adults from 1980 through 2000 may be attributed to reductions in major risk factors, and half of the decline was attributed to evidence-based medical therapies. Specifically, they reported a 47 percent decrease attributed to treatments (secondary preventive therapies after myocardial infarction or revascularization, 11 percent; initial treatments for acute myocardial infarction or unstable angina, 10 percent; treatments for heart failure, 9 percent; revascularization for chronic angina, 5 percent; and other therapies, 12 percent). Changes in risk factors accounted for 44 percent of the decline (reductions in total cholesterol, 24 percent; systolic blood pressure, 20 percent; smoking prevalence, 12 percent; and physical inactivity, 5 percent). Risk factor reductions were partially offset by increases in BMI and the prevalence of diabetes, which accounted for an increased number of deaths (8 and 10 percent, respectively).
In December 2010, the U.S. Department of Health and Human Services released the goals, topics, and objectives for Healthy People 2020 (healthypeople.gov). One of the 42 topics in Healthy People 2020, Heart Disease
1 All participants in the Strong Heart Study are American Indians.
and Stroke, contains 24 objectives plus subobjectives aimed at improving “cardiovascular health and quality of life through prevention, detection, and treatment of risk factors for heart attack and stroke; early identification and treatment of heart attacks and strokes; and prevention of repeat cardiovascular events.”2 The recently released Institute of Medicine report Leading Health Indicators for Healthy People 2020 (IOM, 2011) highlighted 24 objectives to be emphasized from among the nearly 600 Healthy People 2020 objectives. Of those 24, 5 relate to cardiovascular disease or its risk factors. The objectives include:
- Reduce coronary heart disease deaths;
- Reduce the proportion of persons in the population with hypertension;
- Increase the proportion of adults who meet current federal physical activity guidelines for aerobic physical activity and for muscle-strengthening activity;
- Reduce the proportion of children and adolescents who are considered obese; and
- Reduce consumption of calories from solid fats and added sugars in the population aged 2 and older.
WHO has established similar priorities to reduce the incidence, morbidity, and mortality of cardiovascular disease. The aim is to effectively reduce cardiovascular disease risk factors and their determinants; develop cost-effective and equitable healthcare innovations for cardiovascular disease management; and monitor trends of cardiovascular diseases and their risk factors. The strategies that WHO identified for cardiovascular disease prevention include:
- Quitting tobacco use, reducing the amount smoked, or not starting the habit;
- Making healthy food choices;
- Being physically active; reducing BMI (to less than 25 kg/m2) and waist–hip ratio (to less than 0.8 in women and 0.9 in men, although these targets may differ by ethnic groups);
- Lowering blood pressure (to less than 140/90 mmHg);
- Lowering blood cholesterol (to less than 5 mmol/l or 190 mg/dl);
- Lowering LDL cholesterol (to less than 3 mmol/l or 115 mg/dl);
- Controlling glycemia, especially in those with impaired fasting glycemia and impaired glucose tolerance or diabetes (pre-diabetes); and
- Taking aspirin (75 mg daily) after ensuring blood pressure has been controlled.
WHO notes that these goals represent the minimum that should be achieved and that they are offered as broad guidance in managing cardiovascular risks. Individuals at high risk and those with established cardiovascular disease or diabetes may require more aggressive targets (WHO, 2007).
Kahn and colleagues (2008) investigated the effects of 11 nationally recommended prevention activities: providing aspirin to selected individuals, lowering LDL cholesterol in 4 subpopulations, lowering blood pressure in 2 subpopulations, lowering A1C in diabetic individuals, reducing fasting plasma glucose to < 110 mg/dl, smoking cessation, and reducing weight to BMI < 30 kg/m. Using data from NHANES, the investigators sought to determine the number and characteristics of U.S. adults aged 20–80 who are candidates for different prevention activities related to cardiovascular disease. They used the Archimedes model to simulate the U.S. population as well as a series of clinical trials that examined the effects of prevention activities over 30 years and compared the health outcomes, quality of life, and direct medical costs to current levels of prevention and care. They found that approximately 78 percent of U.S. adults aged 20–80 who are alive today are candidates for at least one of these prevention activities, and they concluded that myocardial infarctions and strokes would be reduced by 63 percent and 31 percent, respectively, if everyone received the interventions for which they are eligible. More feasible levels of performance would reduce myocardial infarctions by 36 percent and strokes by 20 percent. The investigators estimated that implementation of all prevention activities would add 221 million life years and
2 See http://healthypeople.gov/2020/topicsobjectives2020/overview.aspx?topicid=21 (accessed August 2, 2011).
244 million quality-adjusted life years to the U.S. adult population over 30 years—an average of 1.3 years of life expectancy for each adult.
Kahn and colleagues (2008) found that the prevention activities associated with the greatest benefits to the U.S. population were providing aspirin to high-risk individuals; controlling pre-diabetes; weight reduction in obese individuals; lowering blood pressure in people with diabetes; and lowering LDL cholesterol in people with existing coronary artery disease. The investigators noted that these prevention activities are expensive, and smoking cessation was the only prevention strategy they found to be cost saving over 30 years. They concluded that aggressive application of nationally recommended clinical prevention activities could prevent a high proportion of coronary artery disease events and strokes that are expected to occur among U.S. adults. However, they cautioned that most clinical prevention activities will substantially increase costs if delivered in the current manner. Reducing cost and increasing efficiency in the delivery of prevention activities were recommended as a means to allow preventive strategies to achieve their potential.
Examining a different service delivery approach, the Task Force on Community Health Services (Soler et al., 2010) conducted a systematic review of selected interventions for work site health promotion and concluded that there was strong or sufficient evidence that assessment of health risks with feedback when accompanied by health education could reduce risk from tobacco use, alcohol use, seat belt nonuse, dietary fat intake, blood pressure, and cholesterol. They also found strong or sufficient evidence that this same intervention strategy could have significant effects on summary health risk estimates, worker absenteeism, and healthcare service use. Baicker and colleagues (2010) conducted a meta-analysis of work site wellness intervention studies and concluded that these programs can improve the health of employees and reduce healthcare costs by more than $3 for every dollar spent on wellness programs and reduce absenteeism costs by nearly the same ratio. They concluded that this return on investment suggests that the wider adoption of such programs could prove beneficial for budgets and productivity as well as health outcomes (Baicker et al., 2010).
Screening for cardiovascular disease risk factors such as high blood pressure and high blood cholesterol are an important means of reaching individuals who may be unaware of their condition and referring them to appropriate care. For example, the Well-Integrated Screening and Evaluation for Women Across the Nation (WISEWOMAN) program provides screening and lifestyle interventions to low-income, uninsured, or underinsured women aged 40–64. The program is administered by the Centers for Disease Control and Prevention’s (CDC’s) Division for Heart Disease and Stroke Prevention, and it currently has 21 programs operating on the local level through states and tribal organizations. WISEWOMAN has reached more than 84,000 women and provided approximately 149,000 health screenings and 210,500 lifestyle interventions since the year 2000. These screenings identified more than 7,674 new cases of hypertension, 7,928 cases of high cholesterol, and 1,140 cases of diabetes (http://www.cdc.gov/wisewoman/about_us.htm).
Blood Pressure Management
The National High Blood Pressure Education Program (NHBPEP) was established in 1972 and is coordinated by NHLBI. NHBPEP is a cooperative effort among various professional and voluntary health agencies, state health departments, and community groups that use professional, patient, and public education strategies to reduce death and disability related to high blood pressure. The NHBPEP works to achieve the Healthy People 2010 objectives for heart disease and stroke prevention by developing and disseminating educational materials and programs, and fostering partnerships among program participants.
The NHBPEP is also responsible for the publication of the Report of the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure, which provides guidelines and recommendations for clinicians and community organizations. The report was first published in 1976 and has been updated five times, most recently in 2003. The reports have been widely distributed: copies are sent to all state health departments as well as the majority of primary care clinicians and all hypertension control programs. Prior to the inception of
NHBPEP, less than one-quarter of Americans was aware of the relationships among high blood pressure, heart disease, and stroke. Hypertension awareness has increased to the point that three-quarters of Americans have their blood pressure checked every 6 months, and 90 percent have it checked every 2 years (NHLBI, 2010a).
The National Cholesterol Education Program (NCEP) was established by NHLBI in 1985 to reduce the percentage of Americans with high blood cholesterol and resulting coronary heart disease. The program educates health professionals and the public about the risks of coronary heart disease associated with high blood cholesterol. Results from the NCEP Cholesterol Awareness Survey demonstrated that from 1983 to 1995, the percentage of the public who had ever had their blood cholesterol measured increased from 35 to 75 percent. The survey also demonstrated a trend toward pharmacologic intervention at lower cholesterol levels and widespread adoption of many NCEP guidelines for blood cholesterol detection and treatment. Data from NHANES III showed a decline in the reported intake of saturated fat, total fat, and cholesterol during the 1980s and 1990s. Average total blood cholesterol levels dropped from 213 mg/dL in 1978 to 203 mg/dL in 1991, and the prevalence of cholesterol of 240 mg/dL or higher declined from 26 percent in 1978 to 19 percent in 1991. Reductions in coronary heart disease mortality support the impact of NCEP’s efforts at reducing high cholesterol (NHLBI, 2010b).
The Obesity Education Initiative (OEI) was launched by NHLBI in 1991 to reduce the prevalence of overweight, obesity, and physical inactivity. The OEI educates professionals and the public about the risks associated with overweight and physical inactivity using two strategies: a population-based strategy and a high-risk strategy. The population approach works within the general population and promotes physical activity and healthy eating by partnering with community organizations such as elementary schools and public parks. Individuals at risk for complications associated with overweight and obesity are the focus of the high-risk strategy. The Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults: Evidence Report (NHLBI, 2010c) was released in 1998 to provide federal clinical practice guidelines for overweight and obesity. The guidelines review the evidence supporting the recommendations and provide strategies for their implementation. They have been adapted for various audiences, including primary care physicians, nutritionists, nurses, pharmacists, health maintenance organizations, patients, and the public.
The National Diabetes Education Program (NDEP) was established in 1997 and is funded by the National Institutes of Health and the CDC. It includes more than 200 partners at the federal, state, and local levels working together to reduce diabetes and pre-diabetes by facilitating the adoption of proven approaches to prevent or delay the onset of diabetes and its complications. The NDEP uses culturally and linguistically appropriate diabetes awareness and education campaigns to increase knowledge of the seriousness of diabetes, its risk factors, and effective strategies for preventing complications associated with diabetes and preventing type 2 diabetes. The NDEP strives to increase the number of people who live well with diabetes, decrease the number of Americans with undiagnosed diabetes, promote effective lifestyle changes, reduce health disparities in populations disproportionately burdened by diabetes, and facilitate the incorporation of evidence-based research findings into healthcare practices.
The CDC’s Office on Smoking and Health (OSH) was established in 1965 to reduce the death and disease caused by tobacco use and exposure to secondhand smoke. OSH created the National Tobacco Control Program (NTCP) in 1999 to encourage coordinated national efforts to reduce tobacco-related diseases and deaths. The program provides funding and technical support to state and territorial health departments. The components of
NTCP are population-based community interventions, counter marketing, program policy/regulation, surveillance, and evaluation. The goals of the program are to eliminate exposure to secondhand smoke, promote quitting among adults and youth, prevent initiation among youth, and identify and eliminate disparities among population groups (http://www.cdc.gov/tobacco/tobacco_control_programs/ntcp/index.htm).
The American Heart Association reports that between 1997 and 2007, the total number of inpatient cardiovascular operations and procedures increased 27 percent, from 5,382,000 to 6,846,000 annually. In 2007, an estimated 1,178,000 inpatient percutaneous coronary intervention procedures were done, and 232,000 patients underwent 408,000 coronary artery bypass procedures. In addition, 1,061,000 inpatient diagnostic cardiac catheterizations were performed (Roger et al., 2010).
Coronary Heart Disease
Particularly striking changes have taken place in the medical management of patients experiencing acute myocardial infarction (AMI) over the past several decades. In the early to mid-1980s, coincident with new insights into the pathophysiology of acute coronary disease, the medical management of AMI evolved from a strategy of watchful waiting and supportive therapeutic interventions to active treatment with aspirin, beta adrenergic blocking agents, thrombolytic therapy, and more recently, the angiotensin converting enzyme (ACE) inhibitors and antithrombotic regimens. Primary coronary angioplasty has been increasingly adopted as the main modality for reperfusion of the infarct-related coronary artery, in conjunction with the use of several adjunctive therapies. The American College of Cardiology and the AHA continue to disseminate and update on a regular basis evidence-based guidelines for the more effective management of patients with AMI with various cardiac medications, as well as for the use of coronary angioplasty in appropriately selected patients.
Despite impressive advances in the management of patients with AMI, limited evidence exists to demonstrate that physicians have uniformly adopted these treatment recommendations in the hospital or after discharge. Potential overuse of unproven or ineffective treatment regimens also may exist, though local surveillance data are not available to examine changing trends in physicians’ management practices. Important differences in the management of hospitalized patients with AMI have been reported among countries, but most of these data are from the distant past. Trends in the use of cardiac procedures, stenting of the coronary arteries, newly developed interventional approaches, and other approaches yet to be incorporated into clinical practice need to be monitored.
Carotid endarterectomy is the surgical procedure performed most frequently to prevent stroke. An estimated 91,000 inpatient endarterectomy procedures were performed in the United States in 2007 (Roger et al., 2010). The procedure is used to remove accumulated plaque from the carotid artery in the neck. Cerebral angioplasty can also be used to treat stroke by using balloons, stents, and coils to increase blood flow to the brain’s vessels (AHA, 2010). Thrombolytic drugs such as tissue plasminogen activators (tPAs) help to dissolve clots that block blood flow to the brain. They are most effective when administered within 3 hours of stroke-onset symptoms. Complications can include brain hemorrhage, but tPA does not appear to increase the death rate in stroke patients when compared to placebo (National Stroke Association, 2011).
The Seventh Report of the Joint National Committee on the Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (Chobanian et al., 2003) provides guidelines for hypertension treatment. The authors note that most hypertensive individuals over age 50 will achieve their diastolic blood pressure goal once systolic blood pressure is controlled; epidemiologic data support an emphasis on systolic blood pressure control. Lifestyle modi-
fications to lower blood pressure include weight management in those who are overweight or obese, a diet rich in potassium and calcium (e.g., the DASH diet), reduced sodium intake, increased physical activity, and moderation of alcohol consumption. Chobanian and colleagues note that a reduced sodium diet such as DASH is as effective as single drug therapy in controlling hypertension, and that two or more lifestyle modifications can yield even greater benefits. Drugs that have been shown to be effective in lowering blood pressure include ACE inhibitors, angiotensin receptor blockers, beta-blockers, calcium channel blockers, and thiazide-type diuretics. The Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) demonstrated the effectiveness of diuretics in preventing the cardiovascular complications of hypertension. Diuretics are affordable and can enhance the antihypertensive efficacy of multidrug regimens, yet they remain underused (Chobanian et al., 2003).
Treatment for heart failure depends on the severity of the condition, and it includes lifestyle changes, medications, and surgical intervention. Lifestyle modifications such as maintaining a healthful diet, drinking enough fluids, and controlling other risk factors (e.g., hypertension, diabetes, smoking, overweight, obesity) are recommended. Diuretics, ACE inhibitors, aldosterone antagonists, angiotensin receptor blockers, beta-blockers, isosorbide dinitrate/hydralazine hydrochloride, and digoxin are medications that may be prescribed to treat heart failure. A cardiac resynchronization therapy device or implantable cardioverter defibrillator may be indicated in cases of severe heart failure and heart damage. A mechanical heart pump may be used as a precursor to surgery or as a long-term treatment. Heart transplant is employed as a final life-saving measure for end-stage heart failure when other interventions have been unsuccessful. An estimated 111,000 inpatient implantable defibrillators and 358,000 pacemakers were inserted in the United States in 2007 (Roger et al., 2010), and 2,211 heart transplants were performed in 2009 (UNOS, 2010).
Substantial progress has been made in reducing CVD mortality rates. Even so, this group of diseases remains the leading cause of death in the United States. It also is a leading cause of morbidity and high costs. Of special concern is the disproportionately large burden of CVD on women, some minority groups, people living in certain geographical areas, and people with diabetes. This disparity exists to a great extent because the benefits of declining mortality trends have not been enjoyed by these population groups.
Considerable opportunity exists for further reducing CVD and its complications by improving and applying more widely the disease prevention and control strategies that are currently available, and also using more effective public health strategies. However, new and more effective disease control tools and strategies are also needed. Developing and implementing effective disease prevention and control strategies requires surveillance that tracks the burden of disease in the population; leads to hypotheses about etiologic factors that cause CVD; and provides information about the levels of modifiable risk factors across the entire population of the United States and within its various subpopulations. None of this can be accomplished without a more effective disease surveillance program.
To fully appreciate the burden of disease on the population, mortality rates, incident and recurrent event rates, disability rates, healthcare utilization patterns and rates, economic indicators, and other variables need to be measured and followed over time. Risk factors that need to be tracked include, but are not limited to, behaviors of individuals that generate or mitigate risk, and social, physical, and economic factors that either create risk or preserve health. The data sets that are created through systematic surveillance can, in turn, be used to explore hypotheses of etiology. Summarized by Labarthe (2011), “epidemiologic research with surveillance and program evaluation are required to fulfill the three core functions of public health: to assess the health status of communities and populations, develop policies that will foster conditions in which people can be healthy, and assure that these policies are being implemented with the intended benefits.”
Population health is the ultimate goal of surveillance. Yet the epidemiology of CVD is complex and extends across patients and populations; primary, secondary, and tertiary prevention; advances in each domain of prevention; and clinical case management. The principal findings in several reports are that clinical recommendations and
guidelines are insufficient to change practice. Concerted efforts at the national and local policy levels are needed, including development of the necessary linkages among diverse sources of data and on methods to use data in an efficient and dynamic manner to effect evidence-based clinical and public health policy decisions.
Considerable opportunity exists for further reducing CVD and its complications by improving and applying more widely used prevention and control strategies. National and state data on the prevalence and distribution of CVD and relevant risk factors are available through major national surveys. Such information is important for making decisions about implementation strategies and programs needed for prevention of CVD at the national level and, to some extent, the state level. While these data are particularly useful for national and state decision making, national surveys do not generally have sufficient sample sizes to allow for local population units to understand the disease, risk factor, healthcare, and other important factors specific to their local setting. National surveys also may not measure the factors that are uniquely important in a particular subpopulation. Better local-level data would facilitate development of interventions aimed at the conditions that exist in the specific geographic area. The capability to collect local-level data is necessary to facilitate the development of interventions aimed at the conditions unique to specific geographic areas and specific subpopulations.
Registries, which are useful for obtaining information about individuals who have a particular disease or condition, provide information on incidence of CVD as well as numerous other clinical care data such as treatments, services provided, and follow-up information. Yet registry data do not accurately reflect the population with cardiovascular disease, only those who receive treatment and who are entered into the registry. Because vulnerable populations are less likely to have access to healthcare services, registry data most likely miss large elements of the population who experience the greatest disparities.
Major issues with both surveys and registries are the lack of standardized measures for collecting information and the inability to link data across sources. Of special concern is the persistent disparity in CVD patterns because the benefits of declining mortality trends have not proportionately helped women, some minority groups, certain geographical areas, or people with diabetes. Data gaps also exist in a number of areas: for example, timely and actionable local data are seldom available; data connecting use and cost patterns are hard to access; and data on emerging risk factors, conditions (e.g., atrial fibrillation, heart failure), and uptake of preventive and clinical services are rudimentary.
In summary, sources of data on CVD and its risk factors, largely from national surveys, exist, but there are a number of gaps: (a) the sources are disparate and a “system” that connects the various data sets does not exist; (b) while action is at the local level, data at such a level are lacking; (c) data are not sufficiently used in a dynamic manner to effect policy decisions; (d) greater flexibility and responsiveness of data systems are needed to accommodate rapidly changing population structures, demography, and scientific technological progress; and (e) greater integration of CVD and COPD surveillance is needed. Strengthening surveillance systems will enable timely and appropriate delivery of public health and clinical policy, and it will allow monitoring of trends in CVD risk factors and health status.
AHA (American Heart Association). 2009. Heart disease and stroke statistics—2009 update. Dallas, TX: American Heart Association.
AHA. 2010. Conditions. http://www.heart.org/HEARTORG/Conditions/Conditions_UCM_001087_SubHomePage.jsp (accessed August 2010).
Baicker, K., D. Cutler, and Z. Song. 2010. Workplace wellness programs can generate savings. Health Affairs 29(2):304-311.
Barker, W. H., J. P. Mullooly, and W. Getchell. 2006. Changing incidence and survival for heart failure in a well-defined older population, 1970-1974 and 1990-1994. Circulation 113(6):799-805.
Chobanian, A. V., G. L. Bakris, H. R. Black, W. C. Cushman, L. A. Green, J. L. Izzo, D. W. Jones, B. J. Materson, S. Oparil, J. T. Wright, E. J. Roccella, and National High Blood Pressure Education Program Coordinating Committee. 2003. The seventh report of the joint national committee on prevention, detection, evaluation, and treatment of high blood pressure. JAMA: The Journal of the American Medical Association 289(19):2560-2571.
Ford, E. S., U. A. Ajani, J. B. Croft, J. A. Critchley, D. R. Labarthe, T. E. Kottke, W. H. Giles, and S. Capewell. 2007. Explaining the decrease in U.S. deaths from coronary disease, 1980-2000. New England Journal of Medicine 356(23):2388-2398.
HHS (U.S. Department of Health and Human Services). 2006. Healthy People 2010 midcourse review: Section 12: Heart disease and stroke. Washington, DC: U.S. Government Printing Office.
HHS. 2010. Summary health statistics for U.S. adults: National Health Interview Survey, 2009. Vital and Health Statistics 10(249).
IOM (Institute of Medicine). 2011. Leading health indicators for Healthy People 2020. Washington, DC: The National Academies Press.
Kahn, R., R. M. Robertson, R. Smith, and D. Eddy. 2008. The impact of prevention on reducing the burden of cardiovascular disease. Diabetes Care 31(8):1686-1696.
Labarthe, D. 2011. Epidemiology and prevention of cardiovascular diseases: A global challenge. 2nd ed. Sudbury, Mass.: Jones and Bartlett Publishers.
Lee, E. T., B. V. Howard, P. J. Savage, L. D. Cowan, R. R. Fabsitz, A. J. Oopik, J. Yeh, O. Go, D. C. Robbins, and T. K. Welty. 1995. Diabetes and impaired glucose tolerance in three American Indian populations aged 45-74 years. The Strong Heart Study. Diabetes Care 18(5):599-610.
Lee, E. T., B. V. Howard, W. Wang, T. K. Welty, J. M. Galloway, L. G. Best, R. R. Fabsitz, Y. Zhang, J. Yeh, and R. B. Devereux. 2006. Prediction of coronary heart disease in a population with high prevalence of diabetes and albuminuria. Circulation 113(25):2897-2905.
Moran, A., A. V. Diez Roux, S. A. Jackson, H. Kramer, T. A. Manolio, S. Shrager, and S. Shea. 2007. Acculturation is associated with hypertension in a multiethnic sample. American Journal of Hypertension (20):354-363.
National Stroke Association. 2011. Stroke treatment. http://www.stroke.org/site/PageServer?pagename=treatment (accessed July 29, 2011).
NCHS (National Center for Health Statistics). 2007. United States, 2007. With chartbook on trends in the health of Americans. Hyattsville, MD: Centers for Disease Control and Prevention.
NHLBI (National Heart, Lung, and Blood Institute). 2006. Incidence and prevalence: 2006 chart book on cardiovascular and lung diseases. Bethesda, MD: National Institutes of Health, National Heart, Lung, and Blood Institute.
NHLBI. 2010a. Clinical guidelines on the identification, evaluation, and treatment of overweight and obesity in adults: Evidence report. Bethesda, MD: National Institutes of Health, National Heart, Lung, and Blood Institute.
NHLBI. 2010b. National cholesterol education program. http://www.nhlbi.nih.gov/about/ncep/ (accessed August 2010).
NHLBI. 2010c. National high blood pressure education program. http://www.nhlbi.nih.gov/about/nhbpep/ (accessed August 2010).
Roger, V. L., A. S. Go, D. M. Lloyd-Jones, R. J. Adams, J. D. Berry, T. M. Brown, M. R. Carnethon, S. Dai, G. de Simone, E. S. Ford, C. S. Fox, H. J. Fullerton, C. Gillespie, K. J. Greenlund, S. M. Hailpern, J. A. Heit, P. M. Ho, V. J. Howard, B. M. Kissela, S. J. Kittner, D. T. Lackland, J. H. Lichtman, L. D. Lisabeth, D. M. Makuc, G. M. Marcus, A. Marelli, D. B. Matchar, M. M. McDermott, J. B. Meigs, C. S. Moy, D. Mozaffarian, M. E. Mussolino, G. Nichol, N. P. Paynter, W. D. Rosamond, P. D. Sorlie, R. S. Stafford, T. N. Turan, M. B. Turner, N. D. Wong, and J. Wylie-Rosett, on behalf of the American Heart Association Statistics Committee Stroke Statistics Subcommittee. 2010. Heart disease and stroke statistics—2011 update: A report from the American Heart Association. Circulation 123(4):e18-e209.
Soler, R. E., K. D. Leeks, S. Razi, D. P. Hopkins, M. Griffith, A. Aten, S. K. Chattopadhyay, S. C. Smith, N. Habarta, R. Z. Goetzel, N. P. Pronk, D. E. Richling, D. R. Baver, L. R. Buchanan, C. S. Florence, L. Koonin, D. MacLean, A. Rosenthal, D. Maston Koffman, J. V. Grizzell, and A. M. Walker, for the Task Force on Community Preventive Services. 2010. A systematic review of selected interventions for worksite health promotion. The assessment of health risks with feedback. American Journal of Preventive Medicine 38:S237-S262.
UNOS (United Network for Organ Sharing). 2010. UNOS. http://www.unos.org (accessed August 2010).
WHO (World Health Organization). 2007. Prevention of cardiovascular disease: Guidelines for assessment and management of total cardiovascular risk. http://www.who.int/cardiovascular_diseases/guidelines/Fullpercent20text.pdf (accessed August 2010).
Zhang, Y., J. M. Galloway, T. K. Welty, D. O. Wiebers, J. P. Whisnant, R. B. Devereux, J. R. Kizer, B. V. Howard, L. D. Cowan, J. Yeh, W. J. Howard, W. Wang, L. Best, and E. T. Lee. 2008. Incidence and risk factors for stroke in American Indians: The Strong Heart Study. Circulation 118(15):1577-1584.