Scientists, cardiologists, and heart patients are in a quandary about cholesterol medications. Here’s why: one of the older medicines (statins) which almost everyone thought helped reduce heart attacks and strokes does in fact seem to be of some benefit – but perhaps not for the reasons many researchers believed. And, more troubling, a new medicine (Zetia) which some thought held great promise may actually do more harm than good.
The tangled tale begins with the so-called Framingham study; this was a government study conducted in Framingham, Massachusetts, of 5,000 people who consented to be tracked throughout their whole lives in order to solve the riddle of what causes heart attacks. In 1961, the study indicated that cholesterol could be a factor.
Cholesterol is a fat molecule which the body uses to make hormones and cell membranes. When plaques of cholesterol form unwanted build-ups on artery walls, however, they can become inflamed and break off, triggering clots that block blood flow, causing heart attacks and strokes. The Framingham study singled out LDL or “low-density lipoprotein” as the villain and, in 1977, concluded that LDL (which quickly came to be called “bad cholesterol”) was a risk factor.
In 1994, a Scandinavian study showed that a statin drug called Zocor significantly lowered the death rate of heart patients. Subsequent statin studies in other countries showed the same result.
Now here is where one of the big question marks about statin drugs comes to the fore: a prominent American physician, James K. Liao, was not convinced by the Scandinavian study. Liao, who is currently the head of vascular medicine at Brigham and Women’s Hospital in Boston, was in fact surprised by the results. He was surprised because Zocor prevented strokes as well as heart attacks. The Framingham study had never found a link between LDL and strokes, and Liao suspected that Zocor was doing more than just cutting cholesterol levels.
Liao published his own study in 1997 which showed that Zocor and other statin drugs do indeed stop the body from producing cholesterol, but they also do something else – they also block production of an enzyme called “Rho kinase.” Liao showed that blocking the production of Rho kinase helps prevent damaging inflammation in arteries. When Liao lowered the level of Rho kinase in rats, they didn’t get heart disease. “Cholesterol lowering,” he concluded, “is not the reason for the benefit of statins.”
Other experts disagree with Liao’s findings. Daniel Rader of the University of Pennsylvania, who is one of the world’s leading authorities on cholesterol, said, “We cannot afford to backtrack from our focus on aggressive LDL lowering.”
Another big question mark about the benefit of cholesterol-lowering drugs is raised by “Zetia,” a new medicine which many believe does more harm than good. Zetia lowers cholesterol, but it does it in a manner different from statins. Doctors frequently administer it to patients whose cholesterol remains high even when they are already on statins, often prescribing it in a drug called “Vytorin,” which is Zetia and Zocor combined into a single pill. The question mark – or red flag, as some would have it – was raised because a recent trial of Zetia showed that it did not reduce the growth of arterial plaques. In fact, in patients who took Zetia along with Zocor, plaques actually grew at almost twice the rate of plaques in patients who took Zocor alone.
The hard figures on Zetia and Zocor are as follows: after a two-year study, subjects who took Zocor alone reduced their LDL by an average of 41 percent. Subjects who took Vytorin (the combination of Zetia and Zocor) lowered their LDL by 58 percent. However – and this is key – despite the Vytorin subjects lowering their cholesterol more than the Zocor subjects, the patients taking Vytorin had more growth of arterial plaques in their carotid arteries.
The question of statin drugs is important because the numbers are so big. Over 100 million prescriptions for Zetia and Vytorin have been filled in the U.S. since the FDA approved them several years ago. The drugs cost about $3 a day, and together they account for roughly 20 percent of all cholesterol-lowering prescriptions, topping $5.2 billion in sales last year alone.
Strokes and heart attacks kill about 900,000 Americans every year, and many sincerely believe Zetia and Vytorin can save many lives. Others say that Zetia hurts rather than helps, and that Vytorin is not as good as Zocor alone. Some believe that LDL cholesterol has absolutely nothing to do with heart attacks, and that the only solution for heart-wellness lies in being physically fit. According to Dr. Jerome Hoffman, professor of clinical medicine at UCLA, “The things that really work are lifestyle, exercise, diet, and weight reduction.”
Whose advice should you follow? The answer, of course, is that you should follow the advice of your personal physicians.
(But ask them a bunch of questions.)
© 2008 Newsmax. All rights reserved.
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