TOPICS > Health

New Heart Health Study Could Be Breakthrough for Treating Heart Disease

January 6, 2005 at 12:00 AM EDT


JEFFREY BROWN: For years now, lowering cholesterol has been seen as a key to reducing the risk of heart disease.

Now, researchers have new evidence that another factor, a protein known as CRP, may be just as important.

It’s presented in two studies in today’s New England Journal of Medicine. For the record, one of them was funded by Pfizer, an underwriter of the NewsHour.

Here to tell us about the work is Dr. Peter Libby, chair of cardiovascular medicine at Brigham and Women’s Hospital in Boston, one of the two centers involved in the study.

Dr. Libby, welcome. Tell us in the simplest terms you can what is the importance of today’s news of these studies?

DR. PETER LIBBY: The importance is that it gives us information, which I think is going to help us to provide better therapy and advice for our patients and reduce their risk of heart attacks or dying of a heart attack or a stroke.

JEFFREY BROWN: All right. So let’s walk through it slowly. Tell us first about this protein, it’s a C-reactive protein called CRP.

What is it and where does it come from?

DR. PETER LIBBY: Well, the studies that were reported today looked at people who had known hardening of the arteries that supply blood to the heart, the coronary arteries.

DR. PETER LIBBY: And it took these groups of patients with known disease and treated them with a standard treatment to lower cholesterol or a more aggressive treatment.

And what it found, the first news, is that the lower the cholesterol, the bad cholesterol, what we call the LDL or low-density lipoprotein, the better was the outcome.

In one of the studies, the fatty buildup in the walls of the coronary artery actually shrunk with the more aggressive cholesterol-lowering therapy.

And in the other study, events such as heart attacks or mini heart attacks or dying of coronary heart disease actually was reduced more in those who had the more aggressive cholesterol-lowering treatment.

Now, those results were not terribly unexpected or surprising to those of us who follow the field, but there was a hooker.

There was a really striking, surprising and provocative result that came from these studies, and that was from measuring this danger signal which could be measured in a simple blood test known as the C-reactive protein….

JEFFREY BROWN: The C-reactive protein…. Continue. I’m sorry.

DR. PETER LIBBY: The C-reactive protein actually comes from the liver, but it’s a danger signal that the liver pours out when the body is under stress or attack.

DR. PETER LIBBY: For example, when you have pneumonia or appendicitis, this danger signal, C-reactive protein goes sky high.

What we’ve learned over the last several years is that in apparently well people, if they have C-reactive proteins that are a bit more than average, that they’re at greater risk of having a future heart attack or stroke or complication of hardening of the arteries.

And what’s new about the studies here is that we find that actually the decrease in this protein that’s produced by the statin drugs which were used actually gives a greater clinical benefit than just getting the bad cholesterol down.

So the best outcomes in these studies were in those who had not only a decrease in the bad cholesterol but also a decrease in this danger signal, the C-reactive protein.

JEFFREY BROWN: Now, just to understand more about this protein, what is the connection between it and inflammation, which, of course, has been a big area of study for its impact on heart disease?

DR. PETER LIBBY: Ten or twenty years ago we thought that we understood hardening of the arteries. We thought it was a buildup of this waxy, fatty substance, cholesterol, on the artery wall.

But we learned over the last ten or fifteen years, it started in the laboratory and is now coming actually to the threshold of clinical practice, that there’s much more to the fatty plaque than just waxy cholesterol.

Those lesions are filled — they’re chock-a-block filled with white blood cells that are involved in inflammation, which is nothing more than our body’s defense against invaders or injury.

So the very same kinds of signals, which are triggered when we have an infection or some other kind of insult go up in a lower level but up nonetheless in those who are at risk for coronary artery disease.

JEFFREY BROWN: All right: Let’s get to what people should, doctors and patients should do with this information.

As you said, it’s fairly easily detected with a blood test. If someone has heart disease now or is at high risk for it, what do they do?

DR. PETER LIBBY: Well, nowadays we have some classical, traditional risk factors that most of us know about– high blood pressure, age, the increase in the bad cholesterol and a decrease in the good cholesterol that we call HDL, but this new body of information about inflammation really gives us some new tools, not only to try and pick out those who might be at risk for developing disease.

But it really showed in these groundbreaking studies that were published today that this may actually be a target of therapy.

So like we go to the doctor and get our blood pressure checked, we go to the doctor and get our cholesterol checked, and those who are at risk for heart attacks and strokes, perhaps we need to add this danger signal, this marker of inflammation to the panel of tests that we do in order to follow how we’re doing with therapy.

And it’s very important that the answer to lowering the risk of a heart attack or stroke isn’t always found in the prescription pad or the pill bottle.

DR. PETER LIBBY: A lot of the driver for this information, which is not related necessarily to the cholesterol level, is from the epidemic of obesity that we have, and, of course, that’s due to an unhealthy diet and not enough physical activity.

So the first thing that people should do is to watch their diet and increase their physical activity. That should be part of our daily lives if we want to reduce our risk of having a heart attack in the future.

JEFFREY BROWN: So that hasn’t changed. But let me ask you briefly, and we only have about 30 seconds.

For those who are healthy now, whose cholesterol level is fairly normal, I take it that it’s still a question, an open question whether they should go and get tested for this protein level?

DR. PETER LIBBY: I’m personally not ready to advocate blanket tests of C-reactive protein in the apparently well, low-risk general public.

But I think in those who have family history or have had already some problems with heart disease, that they should get a C-reactive protein test and that we should now be looking to see whether or not we can drive the C-reactive protein low, like we do blood pressure and cholesterol, in order to improve outcomes.

JEFFREY BROWN: All right. Dr. Peter Libby, thanks very much.