by Dr. Ranit Mishori
published in Parade original article

The standard way we doctors determine your personal risk of heart attack is with a tool called the Framingham Risk Score. We plug in various bits of data--age, sex, cholesterol levels, blood-pressure information, diabetes status, smoking history--to get a number. That's your "Risk Score," or the likelihood you will have heart disease in the next 10 years.

These scores are based on data from thousands of people taken over several decades. The numbers are considered fairly reliable, as well as a good incentive for patients with high scores to quit smoking or start exercising more. Lately, however, some researchers have expressed concern that the numbers underestimate certain people's real risk.

Scientists have now discovered sets of risk factors that go beyond the traditional categories. In particular, there is hope that several new blood tests, called cardiac biomarkers, which take readings of various substances that travel in the bloodstream, may quite accurately predict an individual's risk of heart disease.

"In preventive cardiology, we're always looking for ways to sharpen the view in the crystal ball," says Dr. Peter P. Toth, director of preventive cardiology at the Sterling Rock Falls Clinic in Illinois. Cardiac biomarkers, when elevated, "reflect the presence of heart and vascular disease and help identify patients who may warrant aggressive treatment," he adds.

Doctors who want to keep their patients out of trouble and reduce their risk for heart disease, stroke, and sudden death are already ordering some of these tests, and some patients are requesting them. While their usefulness for all patients is still being debated, the following tests are worth discussing with your doctor.

High Sensitivity C-Reactive Protein

A much talked-about study in The New England Journal of Medicine in 2008 found that individuals with high levels of C-Reactive Protein (CRP) but normal cholesterol levels were able to significantly reduce their risk of heart disease and early death by taking a cholesterol medicine. In other words, measuring the level of CRP seems to be a pretty good early warning system. The protein is produced by the liver in response to inflammation in the body. Inflammation affects the buildup of plaque in the linings of arteries--a condition called atherosclerosis--and may lead to heart disease and stroke.

A recent review of evidence published in the Annals of Internal Medicine found that if CRP were measured routinely, "an estimated 11% of men with an intermediate risk would be reclassified into a high-risk category, while an estimated 12% would be reclassified into a low-risk stratum." The test is unreliable on its own but useful where there already is concern. In fact, a growing number of studies have concluded that high levels of high-sensitivity CRP can predict cardiovascular disease, stroke, and death in patients already suffering from cardiovascular disease.

The American Heart Association doesn't yet recommend CRP screening for the general population, but it does for those at intermediate risk for heart disease.

Homocysteine

Homocysteine is an amino acid used to make protein. Higher levels of homocysteine have been linked to coronary heart disease, stroke, and peripheral vascular disease, so a homocysteine test can be a good indicator of risk. But while it's possible to reduce homocysteine levels in the blood--by consuming folic acid, green vegetables, and certain B vitamins, for example--the evidence does not show that doing so actually reduces the risk of heart disease or death from heart disease.

Lipoprotein(a)

A type of LDL (or bad) cholesterol, lipoprotein(a) is generally linked more to genetic makeup than to lifestyle. Medical experts believe that a high level of lipoprotein(a) contributes to the development of atherosclerosis and heart disease. Right now, the experts say, regular LDL levels should be tested first. Testing lipoprotein(a) is recommended if you have atherosclerosis with normal cholesterol levels or if you are not responding well to cholesterol-lowering drugs.

Fibrinogen

High levels of fibrinogen--a protein involved in blood clotting--may indicate an increased likelihood of clots forming in the arteries leading to your heart or brain. Raised levels also are a marker of inflammation, which can worsen atherosclerosis. But a test for this chemical is considered an unreliable predictor of heart disease, because even if levels are high, it's almost impossible to know where the inflammation is. Cigarettes, alcohol, and hormone therapy also may increase fibrinogen levels.

Remember, no single reading on its own amounts to a prediction of heart disease. So do consider these new tests, but be aware that, for now, the traditional risk factors--smoking, high-blood pressure, high cholesterol, and diabetes--are still considered the primary predictors of overall heart health.