A Call for Caution in the Rush to Statins
19 nov 2008--Is it time to put cholesterol-lowering statin drugs in every medicine cabinet?
Judging by recent headlines, you might think so. Last week heart researchers reported that millions of healthy people could benefit from taking statins even if they don’t have high cholesterol.
Although many doctors hailed the study as a major breakthrough, a closer look at the research suggests that statins (like Crestor, from AstraZeneca, and Lipitor, from Pfizer) are far from magic pills. While they clearly save lives in people with a previous heart attack or other serious heart problems, for an otherwise healthy person the potential benefit remains small.
Many doctors who believe in using statins for heart disease say they needn’t be given to healthy patients. Instead, they say, the focus should remain on encouraging healthful behavior and screening for traditional risk factors like high blood pressure and cholesterol.
“Statins have many biological effects that appear to be quite meaningful,” said Dr. Valentin Fuster, director of the heart program at Mount Sinai Medical Center in Manhattan and past president of the American Heart Association. “But I don’t think the answer is a magic drug to prevent disease. The answer is to change behavior.”
Still, the latest study, called Jupiter, is sure to fuel interest in a blood test for something called C-reactive protein, or CRP. The test, which can cost $20 to $50, measures inflammation. Studies have shown that patients with high CRP are at higher risk for heart attack, even if they have normal cholesterol.
The researchers sought out men 50 and older and women 60 and older who had elevated CRP but not high cholesterol. The goal was to determine whether statins could improve their health.
But of nearly 90,000 people who were screened, only 17,802 were selected. That means 80 percent of the recruits were excluded for a variety of reasons — another inflammatory condition like arthritis, medication use, high blood pressure, a history of cancer and so on.
“If you extrapolate that, it means there are not all that many people exactly like those who were studied,” said Dr. Nieca Goldberg, director of the women’s heart program at New York University Langone Medical Center.
“But I can see a lot of people will be wanting a CRP test,” she went on. “My greatest concern is that there will be many people who don’t fit the criteria of the study, but based on this they will get blood tests and statin therapy.”
And because of the way the Jupiter results were reported, many healthy people are likely to get an exaggerated view of statins’ benefits. While the investigators reported an impressive-sounding 50 percent reduction in the risk of serious heart problems among the statin users, in reality everyone in the study had a low risk to begin with.
Only 1.8 percent of the subjects who took a placebo had a major cardiovascular problem during the study period. Among statin users, 0.9 percent did. In other words, the absolute risk of a serious cardiovascular problem (as opposed to the relative risk) was reduced by less than one percentage point.
“Absolute differences in risk are more clinically important than relative reductions in risk in deciding whether to recommend drug therapy,” The New England Journal of Medicine noted in an editorial accompanying a report on the study.
An important indicator of the usefulness of a drug is the “number needed to treat,” a measure of how many people needed to take a pill for just one person to be helped. There is disagreement about what Jupiter showed. The New England Journal editorial concluded that treating 120 people for about two years would help one person. The study authors, using different criteria, came up with a figure of 95.
Some researchers think the number is actually much lower. Extrapolating the data to five years, the study’s authors concluded that just 25 healthy people would need to take a statin to prevent one serious heart problem.
As a result, some doctors say they will start testing for CRP and will offer statin therapy to patients whose levels are high.
“This was definitely a pretty stunning result,” said Dr. Steven E. Nissen, chairman of cardiovascular medicine at the Cleveland Clinic. “I, for one, will be checking CRP in more patients. If it’s elevated, we will be treating them.”
Doctors said one worrisome trend did emerge in the study. In the statin group, 3 percent of the people developed diabetes during the study period, compared with 2.4 percent in the placebo group.
Moreover, because the study was stopped early (so those in the placebo group could begin taking statins for their presumed heart benefits), it did not yield much insight into the drugs’ long-term safety. Nor is it clear that the early benefit shown in the statin group would have held up over a longer period or whether other risks might have emerged.
“This study does not indicate that we should be putting statins in the drinking water or fortifying cereal with statins,” said Dr. Goldberg, of N.Y.U. “There are millions of people who haven’t gone in and even gotten their cholesterol checked, but everybody wants the new thing. They want to believe the new thing will be the total answer.”
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