Blood Test Helps Identify Women at Risk for Heart Attack
March 22, 2000 (Cleveland) -- As many as half of all first heart attack victims are thin nonsmokers with good cholesterol levels. So why do they have heart attacks? That's a question that has bedeviled heart experts for decades, but now they think they may have found a clue: a substance in the blood called C-reactive protein (CRP).
CRP is produced in the liver as part of a response to inflammation in the body. Researchers have speculated for years that inflammation in some way has a role in the development of heart disease. They also have known that CRP levels are higher in people with heart disease, but just recently they developed a new test that detects levels of "high-sensitivity CRP" in the blood. Called hs-CRP, this is the substance that now has cardiology researchers' hearts racing.
Researchers studying data collected from a study of more than 20,000 postmenopausal women say that an elevated level of hs-CRP can predict a first heart attack, and it can make that prediction even in a woman whose LDL -- or bad cholesterol -- is at 130, the recommended goal level. This, says Jonathan Abrams, MD, an expert in prevention of heart disease, is big, big news. These results may change the way heart specialists assess the risk of heart attack, he says.
One of the researchers who is studying the role of hs-CRP, Paul M. Ridker, associate professor of medicine at Harvard School of Medicine in Boston, tells WebMD that this latest study actually compared the reliability of 12 different "markers" for heart disease. Among those were cholesterol, cigarette smoking, obesity, and diabetes -- all known risk factors for heart disease. "High-sensitivity CRP was the strongest single predictor," he says. Ridker reports that the risk of heart attack was more than four times higher for women with the highest levels of hs-CRP, compared to those with the lowest levels.
Ridker says this finding means that it may be time to consider using powerful cholesterol-lowering drugs, called statins, in women with elevated hs-CRP. Some large studies of these drugs have found that they can reduce the number of heart attacks among people with only moderate elevations in cholesterol. Because elevated hs-CRP appears to increase risk even in women whose "LDL is at goal levels, it may be that initiating statin therapy could prevent first heart attack."