Under the 1993 National Cholesterol Education Program guidelines, about 15 million Americans between the ages of 20 and 79 would have been considered candidates for the drugs -- called statins -- for the primary prevention of cardiovascular problems, the researchers say. But the guidelines revised last year expand the number of potential patients to 36 million, an increase of 140 percent.
Almost a third of those eligible are under 56, while 27 percent are 65 or older, according to the new report, which appears in the Jan. 15 issue of Circulation: Journal of the American Heart Association . Moreover, the number of people age 45 and under -- the group the study authors say has been least studied -- rose 201 percent, to 12 million, under the revised guidelines."We're urging caution," say Donald Fedder, a University of Maryland pharmacologist and lead author of the study. Statins are safe in the short term, Fedder says, but doctors "need to follow their patients over a period of time to watch what may happen" as they take the drugs. The compounds may cause abnormal liver function, and at least one version of the pills, which was recalled, was linked to kidney failure.
However, officials at the National Institutes of Health, which issued the guidelines, challenged the latest findings. Dr. James Cleeman, director of the National Cholesterol Education Program, says the researchers' conclusions are flawed and based on erroneous numbers.
Moreover, he says, the report "expresses concern about an increase in people eligible to receive drug treatment, but it doesn't look at the fact that there are many more people at high risk. That's why the numbers went up. I do not think this paper should cause any concern for physicians," Cleeman adds.
The new guidelines combine the growing realization that elevated cholesterol early in life can cause deadly cardiovascular consequences later, and convincing evidence that statin drugs are highly effective at controlling runaway low-density lipoprotein (LDL), the so-called "bad" form of the blood fat.
But studies that have proved the efficacy of statins have covered people between their 40s and early 70s, Fedder's group says. As many as 40 percent of those now eligible to take the drugs fall outside that age range.
The new guidelines also force a significant shift in the proportion of men and women who'll probably receive cholesterol-lowering medication. Under the earlier recommendations, the two sexes were roughly equal in eligibility. Now, men make up 55 percent of the pool and women 45 percent.
Fedder says that's not clinically important, though it might have economic and policy implications.
Cleeman, however, argues that the reason statins haven't been studied in younger patients is that it would take decades to get a good sense of how much heart and vessel protection the drugs provide in this population. Neglecting to treat patients with risk factors for heart disease would be irresponsible, he says.
Dr. Sidney Smith, chief science officer for the American Heart Association, takes the middle ground. "From an academic view, it would be good to have more data in long-term treatment" with statins in younger patients, he says.
"But the harsh reality is we have an epidemic [of heart disease] on our hands, we have medication that can benefit it, and the evidence on hand suggests that it is safe," adds Smith, a professor of medicine at the University of North Carolina in Chapel Hill.
Smith, Fedder and Cleeman also stress the importance of regular exercise and a low-fat diet in reducing cholesterol.
Reining in high cholesterol, either through drugs or changes in diet and exercise habits, can reduce the odds of heart attack and heart-related death by roughly 25 percent, experts say. Treatment also decreases the needfor bypass surgery, angioplasty and other heart procedures, and lowers the risk of death from non-heart causes.
The new guidelines say all adults over age 20 should have a cholesterol screening every five years. Total cholesterol should add up to less than 200 milligrams per deciliter, and scores between 200 and 239 are considered borderline.
Those whose LDL tops 130 mg/dl are at high risk of heart disease and should be put on statins immediately, with the goal of lowering the figure to 100. They also should be encouraged to modify their diets to cut out saturated fats and cholesterol, to lose weight, and to exercise more. That not only lowers LDL cholesterol but boosts high-density lipoproteins (HDL), the "good" form that protects by ferrying fatty molecules away from the heart.
What To Do
If you haven't had your cholesterol screened, ask your doctor about the test. Your total and LDL cholesterol levels are numbers you ought to know.
For more on the latest guidelines, try the National Heart, Lung, and Blood Institute.