The Heart Truth About Heart Disease and Risk Factors, DHHS, NIH, NHLBI

The Heart Truth About Heart Disease and Risk Factors

New research shows that, contrary to popular belief, more than 95 percent of those who die from heart disease have at least one of its risk factors.

Many people believe that as much as 50 percent of heart disease occurs in persons who don't have any of the traditional risk factors, such as cigarette smoking, high blood pressure, high blood cholesterol, overweight/obesity, physical inactivity, and diabetes.

But the new studies explode that myth and help to complete the picture of risk begun a few years ago, when researchers reported that those without risk factors have a low likelihood of developing heart disease—as well as stroke and cancer. According to those findings, persons without risk factors had 72 to 85 percent fewer deaths from heart disease and stroke than persons with risk factors. Those at low risk also lived about 6 to 10 years longer than those with risk factors. Researchers estimate that only about 10 percent of Americans are at low risk for heart disease.

"This is powerful new evidence that heart disease and risk factors go hand in hand and that preventing or controlling risk factors will greatly lower a person's chance of developing heart disease," said Dr. Barbara Alving, acting director of the National Heart, Lung, and Blood Institute (NHLBI). "The only way we can fight the epidemic of heart disease in the United States is by taking these risk factors seriously."

Published in The Journal of the American Medical Association (JAMA), this research comes from clinical and observational studies of more than 500,000 women and men. The studies include such landmark investigations as the Framingham Heart Study and the Multiple Risk Factor Intervention Trial.

The research also found that heart disease risk is "dose-dependent:" The worse a particular risk factor is, the higher the chance of developing heart disease. For example, the higher the high blood pressure, the greater the heart disease risk.

"Heart disease risk factors act in two ways," said Alving. "They act independently to increase risk. But they also act in concert, worsening each other's effects. So, having any one risk factor is bad but having more than one greatly multiplies the danger."

According to focus-group research by the NHLBI, many Americans do not have a realistic view of their risk status. The research, done among women, also indicated that persons often do not understand the connection between risk factors and their personal risk of heart disease.

"We need to get the word out that risk factors are a real threat," said Alving. "But Americans also have to know that it's never too late to take steps to protect their heart health. Often all that's needed are changes in lifestyle. It's been found that leading a healthy lifestyle can lower heart disease risk by 82 percent. In most cases, this means following a heart-healthy eating plan, getting regular physical activity, maintaining a healthy weight, and not smoking."

Key findings from studies of the relationship between heart disease and its major risk factors include:

Increased risk-

More than 95 percent of those who die from a coronary event, such as a heart attack, have at least one major risk factor
Eighty to 90 percent of those who develop symptoms of heart disease have at least one major risk factor
Major risk factors have a continuous dose—dependent effect on heart disease—the worse each risk factor, the greater the heart disease risk
Women tend to have more major risk factors than men
The association between major risk factors and risk holds for men and women, and a broad range of ages
Up to 90 percent of those with early heart disease have at least one major risk factor—cigarette smoking is the most common

Decreased risk-

Those without major heart disease risk factors are unlikely to develop heart disease
Heart disease accounts for a smaller portion of all deaths among those at low risk than those at high risk
There are fewer deaths from heart disease and stroke among those at low risk for heart disease
There are fewer deaths from cancer among those at low risk
There are significantly fewer deaths from any cause among those at low risk—by 40-58 percent—and their life expectancies are about 6 to 10 years longer
Those at low risk in mid-life have lower average annual medical care costs in older age than those at high risk

Take Action To Lower Heart Disease Risk:

Don't smoke. Smokers had a coronary event at least 10 years sooner than non-smokers—regardless of the presence or absence of other major risk factors. But deaths dropped by 36 percent among those who'd stopped smoking.
Eat for heart health. If you have high blood pressure or high cholesterol, follow an eating plan low in saturated fat and cholesterol, and limit your intake of salt and other forms of sodium. Those with high cholesterol should increase their intake of soluble fiber and cholesterol-lowering foods; those with high blood pressure who drink alcoholic beverages should do so in moderation.
Be physically active. Regular physical activity helps prevent and control heart disease and its major risk factors.
Aim for a healthy weight. If you are overweight, aim to lose no more than ½ to 2 pounds per week.

Sources for information in this fact sheet include the following articles from The Journal of the American Medical Association: "Low Risk-Factor Profile and Long-Term Cardiovascular and Noncardiovascular Mortality and Life Expectancy," Dec. 1, 1999, and "Major Risk Factors as Antecedents of Fatal and Nonfatal Coronary Heart Disease Events" and "Prevalence of Conventional Risk Factors in Patients With Coronary Heart Disease," both August 20, 2003.