HEART HEALTH

March 23, 2000
		A study published in the New England Journal of Medicine presents a simple blood test that can predict heart attack risk. Margaret Warner talks with Dr. Paul Ridker about his study. The Health Unit is a partnership with the Henry J. Kaiser Family Foundation.

Nov. 11, 1999: Ramipril for preventing heart attacks and diabetes. July 20, 1999: Aldactone found surprisingly effective. May 27, 1999: Seeking hospitals for heart care. Nov. 11, 1998: Gains in the fight against Heart Disease. April 13, 1998: Smoking and Heart Disease. June 19, 1997: Estrogen and Heart Disease. April 3, 1997: Heart disease risks. The NewsHour's Health Spotlight. Browse the NewsHour's coverage of Health   Article in the New England Journal of Medicine Brigham and Women's Hospital American Heart Association	MARGARET WARNER: There's a startling new finding in today's "New England Journal of Medicine." Researchers at Brigham and Women's Hospital in Boston found that a simple, inexpensive blood test proved far more accurate in predicting future heart attack risk than the test now commonly relied on, namely cholesterol screening. Joining us to explain the findings is the man who led the research team, Dr. Paul Ridker. He's director of the Center for Cardiovascular Disease Prevention at Brigham and Women's Hospital, and associate professor of medicine at Harvard Medical School. Dr. Ridker, welcome, thanks for being with us. DR. PAUL RIDKER, Brigham and Women's Hospital: It's a pleasure. Thank you. MARGARET WARNER: Now, what does this blood test measure and how does it relate to a person's risk for heart attack? DR. PAUL RIDKER: Well, the key issue for us is that while cholesterol is a very important risk factor for heart attack and for stroke, reality is that half of all those events which will occur, occur among individuals who actually have normal levels of cholesterol. What we attempted to, therefore, do was try to find out whether we could do a better job predicting heart attacks, and therefore, hopefully do a better job actually preventing these events. The test that we described is a marker of a very different process than cholesterol. It's a marker of inflammation or the process by which our bodies responds to a variety of different types of injuries. It turns out you can measure that inflammatory response and those of us that have a greater response turn out to be at much higher risk of going on to have either a heart attack or a stroke.
	Cholesterol vs. protein level
	MARGARET WARNER: So, even if you have very low cholesterol if you have a high-level of this protein, you are definitely at risk? DR. PAUL RIDKER: Well, what it turns out is that the cholesterol level seems to tell us about how much of the hardening of the arteries or the atherosclerosis will build up inside those vessels, but the key issue is that some individuals go beyond just having that and the plaque becomes vulnerable, or it actually ruptures. MARGARET WARNER: So it breaks away? DR. PAUL RIDKER: That's exactly right. The rupturing of that plaque is what determines who actually has the event. What the protein is is a very simple protein, something called C-reactive protein that your liver makes in response to a variety of this inflammatory process. But you can measure this with a very high sensitivity test, something call H. S. or high sensitivity C-reactive protein. And even among individuals with low levels of cholesterol those with high levels of this test clearly were at high risk. MARGARET WARNER: All right. Let's flip it around. What if you have high cholesterol and you work on that all the time. But you go take this test and you don't have much of this protein. Then can you breathe easy, have butter? DR. PAUL RIDKER: No, probably not. I think that the cholesterol levels remain very important. The key issue is that risk is a global marker, and individuals who have a cholesterol problem, and have this inflammatory problem are at very high risk. But those individuals who just have the cholesterol or just have the inflammation, they too are at substantial risk and need to be very careful about diet and exercise and stopping smoking and those type of things. MARGARET WARNER: A couple of other questions just about how wide this study is, this was on post menopausal women. Does it also apply to premenopausal women or men - is there any reason to think it wouldn't? DR. PAUL RIDKER: Well, actually the current study derives from a federally funded study called the Women's Health Study. We tracked some 25,000 women who were healthy at base line in the future to see if we could predict their future heart attacks and strokes. But very similar data presented in middle aged men. Several studies have shown this to be a very real and predictable phenomena. And each of these studies has told us that measuring this novel parameter - this blood test -- does do a better job of predicting heart attack risk and clearly adds to our ability to predict risks over and above the lipid level. MARGARET WARNER: Does it also apply to stroke, predicting stroke risk? DR. PAUL RIDKER: Well, yes, it does, and that's a very important insight. Stroke is a devastating disease that really our job must be to prevent it from happening. But the problem is that cholesterol screening actually does not predict stroke at all. Yet again this inflammatory process which seems to lead to a plaque rupturing in that blood vessels supplying, in this case blood to the brain, also can be predicted by this high sensitivity test for c-reactive protein.
	Treating the risk
	MARGARET WARNER: All right. Now, if you are a healthy, otherwise healthy person and you, your doctor finds you have this protein, then what treatment is suggested? DR. PAUL RIDKER: Well, I'm a cardiologist who believes that I've done my job well if my patients never really need my services and can I prevent that first heart attack or that first stroke from occurring. So the recommendation would be initially to encourage a patient to stop smoking, to diet, to exercise and to be compliant with their medications. But we've also learned that this process of inflammation and the destabilization of that plaque can actually be improved by some very simple types of medications which are well known to reduce the risk of heart attack. MARGARET WARNER: Like? DR. PAUL RIDKER: The first of these is aspirin. A drug which we know drops the risk of a heart attack turns out to actually modulate or attenuate this inflammatory response. The second class of drugs are the statin drugs that seem to lower the LDL cholesterol but also they have a number of other next. And in one of the very interesting twists to this whole story is that at least one of these agents, pravostatin, seems to reduce the level of this actual marker, the high sensitivity C- reactive protein. MARGARET WARNER: So, in other words, even though we thought of it as working on lipid levels it also has an anti-inflammatory effect? DR. PAUL RIDKER: Well, that seems to be the case. And the biology of what causes these heart attacks and strokes in the first place tells us that inflammation is very important. So it's very exciting to discover that some of these drugs that are very effective at reducing risk turn out to actually impact upon that process. MARGARET WARNER: And then are there other drugs that strictly treat inflammatory, inflammation like, I don't know, arthritis drugs or something? DR. PAUL RIDKER: Well it is an interesting question because fundamentally what we're learning as physicians and I think is important for the patients is that atherosclerosis or the process of hardening of the arteries is very much an inflammatory disease just like rheumatoid arthritis is an inflammatory disease. And the key insight I think from these types of studies and from the basic biology is that we will be seeing many novel drugs that really do target this inflammatory response that traditionally have been used to treat arthritis. These agents may now go into clinical trials to see if we have a very new way of actually treating and hopefully preventing heart attacks from occurring at all. MARGARET WARNER: So you are talking about really a revolution in our concept of what heart disease is? DR. PAUL RIDKER: Well, that's right. This revolution has been going on now for about ten or fifteen years in the basic science laboratories, but I think what our data do is really put this right in the lap of everyday physicians. We can measure this process and measuring that process can give us a handle on who is truly at high risk and also give us a handle on how to better understand why some individuals who after being screened for cholesterol seem to be at low risk, nonetheless go on to have a heart attack. MARGARET WARNER: I need to ask one quick question. Can you get this test now and what do you ask for? DR. PAUL RIDKER: Yes, the test has been released by the Food and Drug Administration about six to eight weeks ago. It is available through standard outpatient testing if the physician asks for a high sensitivity C R P. And it is about the same price as a cholesterol test, $15, $20, in this range. MARGARET WARNER: All right. Dr. Ridker, thanks very much. DR. PAUL RIDKER: It's a pleasure.