This is an interview excerpt by Discover Magazine with Nortin Hadler M.D, a professor of medicine at the University of North Carolina at Chapel Hill.
The full interview can be found here:
http://discovermagazine.com/2005/jun/discover-dialogue
Bypass surgery belongs in the medical archives . . . No Western European nation has as high a rate of bypass surgery and angioplasty as we do—and they live longer
Under what circumstances do you think bypass surgery is appropriate?
H: None. I think bypass surgery belongs in the medical archives. There are only two reasons you’d ever want to do it: one, to save lives, the other to improve symptoms. But there’s only one subset of the population that’s been proved to derive a meaningful benefit from the surgery, and that’s people with a critical defect of the left main coronary artery who also have angina. If you take 100 60-year-old men with angina, only 3 of them will have that defect, and there’s no way to know without a coronary arteriogram. So you give that test to 100 people to find 3 solid candidates—but that procedure is not without complications. Chances are you’re going to do harm to at least one in that sample of 100. So you have to say, “I’m going to do this procedure with a 1 percent risk of catastrophe to find the 3 percent I know I can help a little.” That’s a very interesting trade-off.
So you believe the vast majority of those who have had this major surgery have suffered through it for no reason? That seems so counterintuitive. Everyone seems to know a father or uncle who’s been given a new lease on life after their bypass surgery, with more energy and less chest pain.
H: This analysis is upsetting for people to hear—feel free to yell at me if you need to. I’m really asking people to rethink common sense. But people don’t realize that angina is an intermittent illness. It comes and goes. You can have it for months and then months off. Classic cardiologists used to help people handle the symptoms by treating it like a chronic illness. Well into the 1960s and 1970s, they helped people cope with the anticipation of pain, prescribing drugs like nitroglycerine and helping patients learn to wait until things calmed down a little bit.
But for those people bypass surgery helps, it’s not intermittent—it makes the pain go away altogether. Isn’t that worth something?
H: You have to consider how much of that relief is a function of natural history and placebo effects. In one controlled trial of surgery for angina, half the people with the condition underwent an operation in which doctors merely made a skin incision and closed it up; in the other half, the patients had a particular kind of bypass. The numbers from each group whose symptoms were significantly alleviated were about the same. Angina is particularly susceptible to the placebo effect because the anticipation of pain adds to the intermittency of it. FDA-approved pharmaceuticals for alleviating angina have about a 55 percent effectiveness level in randomized controlled trials; the placebo runs about 45 percent. Even if surgery could be proved to alleviate the discomfort, you’d have to consider if that offsets the risks of bypass surgery—about half the patients suffer severe depression after the surgery, a third suffer measurable memory loss, and many never go back to work again. Then there are the added risks of any major surgery.
You analyze the definitive studies and find that the number of people whose lives are saved by bypass surgery, angiograms, and cholesterol-lowering drugs is statistically insignificant—and yet life expectancy has risen since the advent of all three of those treatments. If it isn’t better cardiac care that’s extending lives, what is?
H: The start of the rise in longevity kicked in long before cardiac intervention became popular. Looking at life-course epidemiological studies, the secret lies in two questions: Are you comfortable in your socioeconomic status, and do you like your job? With regard to socioeconomic status, the central question relates to relative wealth—in other words, the smaller the income gap in a given area, the better the longevity. Where the income gap is larger, the poor die sooner. These are powerful associations. The answer does not lie in modern medicine but in modern society.
Surgery is obviously invasive, but why do you object to the widespread prescription of statins, the cholesterol-lowering drugs?
H: In men with normal cholesterol levels, the risk of death for those between ages 45 and 65 over the course of the next five years is only a fraction of 1 percent lower than it is for men with high serum cholesterol in the same category. The most thorough study to date had some 3,000 men with “high” cholesterol levels take a statin every day for five years, while 3,000 similar men took a placebo. When all was said and done, there was no difference in cardiovascular deaths between the two groups. Statins do reduce the risk of heart attack in those who have a strong family history of people in their family having heart attacks very young—but that’s a small percentage of the population. You could argue, looking at the data, that they’re helpful for people who’ve already had one heart attack. But for everyone else, the possible advantage is marginally and clinically insignificant.
If the data are not prompting so much interventional cardiology, what is?
H: Money. Interventional cardiology is what supports almost every hospital in America—it’s an enormous part of our gross domestic product. Every year in this country we do about half a million bypass grafts and 650,000 coronary angioplasties, with the mean cost of the procedures ranging from $28,000 to $60,000. There are a lot of people involved in this transfer of wealth. But no Western European nation has such a high rate of those procedures—and their longevity is higher than ours.