The impact of cardiac risk factors for women under the age of 70 are not as well understood as risk factors in men and in women over 70.  But no matter your age or gender, you should work with your doctor to understand your own risk factors. 

What are risk factors?  They're things that increase your chance of getting a disease or developing a condition.  By definition, risk is uncertain.  If you have a lot of risk factors for a disease, that does not mean you will get it; if you don't have a lot risk factors, that does not guarantee you will not get it. 

But knowledge is power.  If you know you have a lot of risk factors, you can take steps to reduce their effect.

Some risk factors for coronary artery disease and heart attack are beyond our control, such as:

• Genetics: a family history of heart disease and early heart attack can increase one's risk of heart attack.
• A history of coronary artery disease, high blood pressure, and other heart problems.
• Age: the heart muscle weakens with age, so that men over 45 and women over 55 are at a higher risk of having a heart attack.
• Diabetes: uncontrolled diabetes increases the risk of developing coronary artery disease.
• Peripheral arterial disease (clogged vessels in the arms and legs):  people with PAD may form blood clots, increasing their risk of death from heart attack or stroke.
• Chronic renal disease: kidney disease can be a cause or a consequence of cardiovascular disease.  It is also closely related to hypertension and diabetes.

Other risk factors, such as not getting enough exercise, smoking, and having too much cholesterol in the blood, are controllable.  They relate to how we live, and we can always change that if we try; we can always choose to live in a heart-healthy way.  For information about heart-healthy living, go to Key Point 3.

Much of what we know about these risk factors comes from the Framingham Heart Study. Begun in 1948, directed (in collaboration with Boston University since 1971) by what is now the National Heart, Lung, and Blood Institute (one of the National Institutes of Health), the study started with 5,209 people, ages 30-62, from Framingham, Massachusetts, who had no overt symptoms of cardiovascular disease or stroke.  It then tracked their health until the present (or their death) with the goal of  learning "the circumstances in which cardiovascular diseases arise, evolve and end fatally in the general population."

Through regularly scheduled, in-depth medical exams (now including sophisticated new technology such as bone scans, eye exams, and echocardiograms) and interviews, plus information from the subjects' primary care physicians, and other data, the study began the process of identifying major risk factors for CVD.  In fact, the study actually coined the term "risk factor."  Before then, the idea that "risk factors" for specific diseases could be discovered, and people could change their lives to reduce their effect, was simply unheard of. 

In 1971, the "Offspring Study" began, as more than 5000 adult children (and their spouses) of the original participants were enrolled in the research program. Having two generations worth of data created an especially rich source of data. The third generation study, focusing on the children of the 1971 group, began in 2002.

So far, the study has yielded more than 1200 scholarly research articles. Perhaps more important, it has made so many "ordinary people" aware of how high blood pressure, high blood cholesterol, smoking, obesity, diabetes, and physical inactivity can increase the risk of heart disease. 

It has also produced a coronary prediction algorithm, a risk assessment tool that estimates a person's risk of having angina or a heart attack, or dying from heart disease, during the next ten years.  The risk factors considered include age, "good" and "bad" cholesterol, blood pressure, smoking, and diabetes.  Separate score sheets for men and women indicate a person's risk score or risk classification.

Finally, the study has deepened our understanding of the effects of gender, age, and psychosocial issues on heart disease.  There seem to be important differences in the way risk factors affect men and women, and some different factors for each.  Among these differences are:

• Both men and women have coronary heart disease (CHD) more often than other cardiovascular events such as stroke or congestive heart failure.
• At younger ages, men suffer coronary events twice as often as women; but as people age, the numbers become almost equal.
• For women, angina (chest pain) is the most common first symptom of CHD; 
  for men, heart attack is the most common first coronary event.
• Women with angina do better than men, because men with angina have more underlying heart disease. 
• Women with angina have five times the risk of future coronary events than women without angina.
• More women than men have unrecognized heart attacks. 
• When heart attack is the first coronary event, nearly half are unrecognized in women, one-third in men.  
• Most men and women with unrecognized heart attacks had either no symptoms or such unusual symptoms that neither they nor their physician suspected a heart attack.  Routine ECGs revealed the heart attacks.
• Heart attacks are more often fatal for women than men, but women heart attack survivors generally have the same prognosis as men.
• Menopause seems to increase a woman's risk of  heart disease.
• Diabetes poses a greater risk of CHD in women then men.
• Women who smoke heavily (two packs daily) are less likely to quit than men.
• Both men and women who "weight cycle" (repeatedly loss weight then gain it back) have a higher risk of heart disease, including fatal heart disease.

More research is needed to explain these differences, although some have been addressed in the American Heart Association's "2007 Guidelines for Preventing Cardiovascular Disease in Women."   For more information on these guidelines, go to Key Point 3.