TOPICS > Health

Lowering Cholesterol

July 13, 2004 at 12:00 AM EDT


GWEN IFILL: New guidelines on cholesterol. Millions more Americans, those considered at increased risk for heart disease or stroke, should be aiming even lower. A new study says bad cholesterol, or LDL, should measure 70 or less in the highest risk patients, down from 100. And those at a slightly lower risk should aim for a bad cholesterol measure of 100, down from the previously recommended 130. To help us better understand what people should and should not do now, I’m joined by Dr. James Cleeman of the National Cholesterol Education Program at the National Heart, Lung and Blood Institute. Dr. Cleeman, overall, what do these new guidelines… how important is it that the new guidelines be met?

DR. JAMES CLEEMAN: Overall, it’s very important that physicians and the public pay attention to the new evidence. What the overall message is, is that the lower the better when it comes to LDL bad cholesterol for people at the highest risk of having a heart attack. And that is because the evidence now shows that when the LDL is reduced to well below the 100 standard goal– say, to less than 70, which is what is offered as an option in the update– the risk for heart disease goes down dramatically.

GWEN IFILL: You know, when we do these cholesterol studies from time to time, we get a little caught up sometimes in what the meanings are, because we know there is good cholesterol; there’s bad cholesterol. What is LDL exactly?

DR. JAMES CLEEMAN: LDL stands for low density lipoprotein. And the reason that a lipoprotein comes into play at all is that the blood is watery, but cholesterol is a fatty substance, and we all know that oil and water don’t mix. So in order to be carried in the blood, cholesterol travels in packages of lipid, which is fatty, and protein, which is water soluble, and as a result, the cholesterol can get to where it’s going. Low density lipoprotein, LDL, is the form of cholesterol that is going toward the tissues, including the arteries of the body. And so LDL cholesterol, when it is too high, can deposit cholesterol in the arteries, leading to plaque buildup and eventually to a heart attack.

GWEN IFILL: When we say that people at the highest risk are the ones we have to worry about, who is high-risk?

DR. JAMES CLEEMAN: High-risk– of which highest- risk is a subset– high-risk are the people who have heart disease or diabetes or multiple- risk factors for heart disease, and a calculated more than 20 percent risk of a heart attack in the next ten years. And people can calculate their risk on our Web site, which I will be glad to provide at some appropriate point. The people who are at high risk, as you’ve said, have an LDL goal of less than 100. But the people at very high risk– and now this is a subset of the high-risk group– these are the people who have a combination of heart disease and diabetes or heart disease, and a very bad risk factor like continued smoking or who are currently hospitalized for a heart attack; all of these people are at high risk for bad outcomes, bad results. And these people now have an option, and it is a preferred option, to get their LDL to less than 70 in order to bring their risk down to acceptable levels.

GWEN IFILL: So how many people are we talking about, if this is a subset of a subset of the general population?

DR. JAMES CLEEMAN: We had previously estimated, when we released the guidelines in 2001– the guidelines are called Adult Treatment Panel 3, or ATP3– when those were released in 2001, we did an estimate that approximately 36 million people would require the addition of drug treatment to their basic lifestyle therapy. And lifestyle therapy is the foundation for cholesterol lowering.

GWEN IFILL: Exercise, diet…

DR. JAMES CLEEMAN: Diet, low saturated fat, physical activity and weight control. And everybody who needs to lower their LDL bad cholesterol should do that lifestyle therapy. But for the 36 million who have to add the drug therapy– I use the word “add” advisedly; it’s add to the lifestyle therapy– we would estimate that several million additional people would now qualify for drug therapy based on today’s update. It’s not a vast increase, but it is an increase of several million people. We are doing a formal estimate of this as we speak.

GWEN IFILL: When you say drug therapy, you are talking about the widely discussed statins, right?

DR. JAMES CLEEMAN: Statins are a very effective LDL-lowering set of drugs, but there are other drugs. Statins are the preferred drugs in the hands of physicians because of their ease of use, and because they do lower LDL very substantially.

GWEN IFILL: And what do they do?

DR. JAMES CLEEMAN: What statins do is, they interfere with a crucial enzyme in the process of constructing or manufacturing cholesterol. When the cholesterol manufacture or production is interfered with, the liver notices that it has less cholesterol to work with. It then up-regulates, it increases the activity of receptors on the surface of the liver that are called the LDL receptors. It grabs LDL out of the blood and lo and behold, the LDL Level in the blood goes down. So it is a multistage process, but starts with the interference by the statins in the manufacture of cholesterol.

GWEN IFILL: Are there side effects of the use of these kinds of drugs?

DR. JAMES CLEEMAN: Every drug has side effects. Aspirin has side effects. As a class, statins are a remarkably safe drug, and in the clinical trials and clinical practice has been very good. But there are side effects that people should be aware of, and these include about 1 percent of people who take statins will notice an increase in their liver enzymes, and about one in a thousand will have a muscle problem, soreness, achiness, maybe even weakness. And very, very rarely, less than one in a million might have a severe muscle problem called, in a fancy term, rabdomyalisis. And it is important to pay attention —

GWEN IFILL: That’s muscle wasting disease?

DR. JAMES CLEEMAN: Yes. That’s the muscle wasting — and it is important to pay attention to the early signs, achy, soreness, weakness, in order not to go on to the other more serious problems. But overall, when people who qualify according to the guidelines take the drug, the benefits vastly outweigh the risks.

GWEN IFILL: Why do these numbers keep getting revised downward, downward, downward? Is it just physicians trying to minimize risk or is this new information we are discovering?

DR. JAMES CLEEMAN: It is new information. But it isn’t a new model of what cholesterol does. It is not a new paradigm. We have known for a long time that, as you come down the levels of LDL cholesterol, the risk for heart attack goes down. What’s new, however, is that these clinical trials that we have seen the results of recently have shown us that even at the lowest levels of cholesterol, of LDL cholesterol, it is worthwhile to continue lowering the level, because it is flattening somewhat. This curve that associates LDL with heart disease is flattening. You are getting slightly less return on your lowering of LDL, but you are still getting about a 1 percent overall reduction in risk for a 1 percent reduction in LDL every 1 percent reduction in LDL gives you a 1 percent reduction in risk. And so the trials are telling us do this for highest-risk people.

GWEN IFILL: But is there a gap between the number of people diagnosed with having potentially dangerous levels of cholesterol and the number of people who are prescribed treatment for it?

DR. JAMES CLEEMAN: There is a treatment gap for sure. As I said, we estimated that about 36 million people would qualify for drug treatment. Roughly half or slightly more than half of that number are currently taking statins. So we have seen a picture of under treatment of high cholesterol levels, even for high-risk people. What we need to do is encourage the physicians and the public to pay attention to this update, and to turn under treatment into appropriate treatment.

GWEN IFILL: This would be the appropriate time to tell us your Web site.

DR. JAMES CLEEMAN: The Web site is, that’s the Heart, Blood and Lung Institute Web site and from there people can navigate to the ten-year risk calculator.

GWEN IFILL: Dr. James Cleeman, thank you very much for being here.

DR. JAMES CLEEMAN: My pleasure to be here.