Surprising discovery: Scientists say inflammation even worse for the heart than cholesterol
By Daniel Q. Haney
Associated Press
BOSTON -- Worse than cholesterol? Hard to believe, perhaps, but the top health concern of millions of Americans is about to be trumped by what doctors say is an even bigger trigger of heart attacks.
The condition is low-grade inflammation, which may originate in a variety of unlikely places throughout the body, including even excess fat. New federal recommendations are being written that will urge doctors to test millions of middle-aged Americans for it.
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Doctors call it a revolutionary departure from viewing the world's top killer as largely a plumbing problem blamed on cholesterol-clogged arteries, the standard theory through the modern era of cardiology.
"The implications of this are enormous," says Dr. Paul Ridker of Boston's Brigham and Women's Hospital. "It means we have an entire other way of treating, targeting and preventing heart disease that was essentially missed because of our focus solely on cholesterol."
The evidence has become overwhelming that inflammation hidden deep in the body is a common trigger of heart attacks, even when clogging in the arteries is minimal. Now the main question is: How aggressively should otherwise healthy people be tested to find and treat it?
The new recommendations are still being drawn up, but they will offer the first formal blueprint to answer this, probably sometime in the fall. Doctors writing them say they will almost certainly recommend broad testing. The recommendations are expected to be published in November.
Inexpensive test
Inflammation can be measured with a generic $10 test that looks for high levels of a chemical called C-reactive protein, one of many that increase during inflammation. Experts expect it to quickly become a standard part of physical exams. As a result, many people ordinarily considered at low risk will probably be put on statin drugs, which lower inflammation as well as cholesterol.
No one disputes the importance of cholesterol. Yet half of all heart attack victims have levels that are normal or even low. Clearly, something big was missing from the equation, and that appears to be inflammation.
Ridker estimates that between 25 million and 35 million healthy middle-aged Americans have normal cholesterol but above-average inflammation, putting them at unusual risk of heart attacks and strokes.
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A series of landmark studies by his team, beginning in 1997, suggest inflammation is more important than cholesterol at triggering heart attacks. They found those with high levels of C-reactive protein have twice the risk of people with elevated cholesterol.
High amounts of the protein also predict increased risk of heart attacks and strokes years before they occur, even when cholesterol levels are low. Having both inflammation and high cholesterol together is especially ominous, resulting in a nine-fold increase in risk.
Everyone who reaches middle age has some degree of fatty buildup, called plaque, in the heart arteries. The new evidence suggests it becomes threatening if weakened by inflammation, which makes it squishy and fragile. Even a small lump of plaque can burst, prompting the formation of a clot that in turn chokes off blood flow and causes a heart attack.
Many people with no outward signs of anything wrong have high levels of internal inflammation. It is exactly the same sort that causes swelling, heat and redness during infections or allergic rashes.
Doctors believe the internal inflammation has many possible sources. Often, the plaque itself becomes inflamed as white blood cells invade in a misguided defense attempt. But inflammation that arises elsewhere apparently can be as bad, for it bombards the plaque with damaging chemicals.
