Cardiovascular disease (CVD) is predominantly caused by atherosclerosis--a hardening of the arteries--due to a thickening of the lining of the arteries. Atherosclerosis results in inadequate blood flow to particular tissues in the body, causing poor function, damage, or death of those tissues. In heart disease and stroke, the principal components of CVD, atherosclerosis affects the arteries of the heart and brain, respectively. CVD accounts for 40 percent of the mortality in the United States, killing about 950,000 Americans annually.(85) Taken as a whole, CVD is the cause of more deaths than the next five causes of death combined.(86),(87)
The Prevalence of Cardiovascular Disease
Heart disease and stroke are the first and third leading causes of death in the United States, respectively, in both men and women. The 2000 age-adjusted death rate from CVD among the general population was 343.1 per 100,000 people.(88)
Coronary heart disease (CHD), caused by blockage of the arteries supplying the heart, is the single leading cause of death within the array of cardiovascular diseases. This year, an estimated 1.1 million Americans will have a new or recurrent coronary attack and more than 45 percent of the people experiencing these attacks will die of them. The age-adjusted 2000 death rate from coronary heart disease was about 186.9 per 100,000 for the total population.(89) Recent studies have demonstrated that the number of sudden deaths from heart disease among people aged 15-34 have increased from 2,719 in 1989 to 3,000 in 1996.(90)
It is commonly believed that CVD primarily affects men and older people. However, research shows that more than half of all CVD deaths each year occur among women.
A consideration of mortality alone understates the burden of CVD. About 61 million Americans (almost one-fourth of the general population) live with some form of CVD, including coronary heart disease, stroke, high blood pressure, congestive heart failure, congenital heart defects, and other diseases of the circulatory system.(91) Prevalence rates for CVD vary by race and ethnicity:(92)
Heart disease also results in significant disability among working adults. Stroke is a leading cause of serious, long-term disability that accounts for more than half of all patients hospitalized for a neurological disease. Of the 4.5 million Americans who have had a stroke, 1 million have been impaired by some form of long-term disability. Almost 6 million hospitalizations each year are due to CVD.(93)
Figure 5. Source: CDC Compressed Mortality Data
Risk Factors for Cardiovascular Disease
As discussed earlier, untreated or poorly treated diabetes can result in cardiovascular disease. In addition, the CDC has identified five key risk factors for CVD: tobacco use, high cholesterol levels, lack of physical activity, poor nutrition, and high blood pressure.
- High blood pressure: About 90 percent of middle-aged Americans will develop high blood pressure in their lifetime, and nearly 70 percent of people with high blood pressure do not have it under control. Of the estimated 50 million Americans with high blood pressure, 31.6 percent are unaware of their condition.(94)
- High cholesterol: About 40.6 million Americans have cholesterol levels of 240 mg/dL or above, which is considered high risk. Meanwhile, a 10 percent decrease in cholesterol levels may result in an estimated 30 percent reduction in the incidence of coronary heart disease.(95)
- Tobacco use: About 1 in 5 deaths from CVD are attributable to smoking. Age-adjusted prevalence rates for Americans 18 and older in 2000 show that 27.1 percent of men and 22.2 percent of women are smokers. The World Health Organization estimates that one year after quitting, the risk of coronary heart disease decreases by 50 percent, and within 15 years, the relative risk of dying from CHD for an ex-smoker approaches that of a lifetime nonsmoker. The risk of death from coronary heart disease increases by up to 30 percent among those exposed to environmental tobacco smoke at home or at work.(96)
- Poor diet leading to overweight and obesity: Using BMI definitions, more than 129 million adults are overweight or obese and 61 million are in the obese category of BMI. (97) In addition, an estimated 5 million children are considered overweight.(98)
- Physical inactivity: The relative risk of coronary heart disease associated with physical inactivity ranges from 1.5 to 2.4, an increase in risk comparable to that observed for high blood cholesterol, high blood pressure, or smoking.(99)
The Costs of Cardiovascular Disease
The costs of CVD have steadily increased past the $300 billion dollar mark over the past three years. The first comprehensive economic analysis based on 2000 Census data, performed by the National Heart, Lung, and Blood Institute (NHLBI) and the American Heart Association (AHA), estimated the total cost of the disease to be $298.2 billion for the year 2001.(100) Subsequent updates to this analysis gave an estimated total cost of $329.2 billion for 2002 and $351.8 billion for 2003.(101),(102)
Figure 6. Source of data: Refs. 100, 101, 102.
The NHLBI/AHA studies of CVD evaluated both direct costs (physician services, hospital and nursing home services, medications, home healthcare, and other durables) and indirect costs of lost productivity resulting from morbidity and mortality (days of work lost due to absence from work or premature death). For the year 2003, these cost categories totaled $209.3 billion and $142.5 billion, respectively. Direct medical care costs covered approximately 66 million physician office visits and 7 million outpatient department visits and over 4 million emergency department visits.(103) CVD ranks highest among all disease categories in hospital discharges. Given the age effects of CVD, it poses a substantial economic burden on Medicare: in 1999, $26.3 billion in payments were made to hospitals for Medicare beneficiaries' expenses due to cardiovascular problems. That was an average of $7,883 per discharge.(104)
The indirect costs of CVD are also substantial; most of these costs are due to lost productivity and are borne by employers. According to the CDC, if all forms of major CVD were eliminated, life expectancy would rise by almost 7 years. The same study indicates that the probability at birth of dying from major CVD is 47 percent. While death rates from CVD have declined over the past ten years, actual (absolute) deaths have increased over the same period of time. (105) Great strides have been made in the treatment of CVD, but treatment can only be part of the solution. An estimated 3 million Americans ages 35-64 who are currently free of coronary heart disease will develop the disease in the next ten years in the absence of intervention to reduce risk factors.(106)