Cholesterol-lowering drugs called statins can dramatically reduce the risk of heart attacks and strokes in patients with heart disease, even if their cholesterol levels already are normal, according to the largest study of the drugs ever conducted.
The research, performed at Oxford University in England, could lead to a major shift in the treatment of heart disease--reducing death rates and the need for surgery. The exchange would be a huge increase in the number of people taking the drugs, already among the most-prescribed medications in the developed world.
"This is a stunning result with massive public health implications," Dr. Rory Collins of Oxford University told an American Heart Assn. meeting in Anaheim on Tuesday. "If an extra 10 million high-risk people worldwide were to go onto statin treatment now, this would save about 50,000 lives a year."
About 25 million people worldwide now take the drugs. Collins suggested that number should be as high as 200 million.
The statins, which include such drugs as Zocor, Mevacor, Pravachol, Lescol and Lipitor, reduce cholesterol levels by blocking the body's synthesis of the fats. They have proved remarkably effective in patients with high cholesterol levels.
But the new study adds to the growing body of evidence that they are equally effective in other patients as well.
"The study showed significant risk reduction in patients regardless of their cholesterol levels," said Dr. Antonio M. Gotto Jr. of the Weill Medical College of Cornell University.
Apparently the drugs have multiple effects on the body that lower heart attack risk by about a third, Collins said.
He compared the findings to the 1980s discovery that daily aspirin doses can prevent heart attacks. "Statins are the new aspirin," Collins said. "But it is not either-or. They add to the benefits of aspirin."
The Oxford trial, called the Heart Protection Study, involved 20,536 patients considered to be at high risk for a heart attack. The patients were chosen because of one or more risk factors, such as a previous heart attack, other heart disease, diabetes, a previous stroke or high blood pressure. Patients were 40 to 80 years old and a quarter of them were women.
The patients were given either Zocor; a combination of vitamins including vitamin C, vitamin E and beta-carotene; the vitamins plus Zocor; or a placebo. All of the patients also received blood pressure medications and other drugs as needed.
Although Zocor was used in the trial, Collins said he would expect similar benefits with any statin.
The patients have now been followed for an average of about five years. Preliminary results reported at the heart meeting indicate that Zocor lowered the risk of heart attacks and stroke by about one-third, even in patients whose cholesterol levels were already considered normal. The drugs also reduced the need for bypass surgery and angioplasty and in diabetics reduced the need for amputations. The statin was equally effective in men and women, as well as in patients older or younger than 70.
The vitamins, by contrast, produced no apparent benefit.
The data "are clear and represent a major step forward in the fight against diseases of the heart and circulation," said Sir Charles George, medical director of the British Heart Foundation. "They emphasize the importance of prevention and extend the range of people who benefit from statin therapy."
Collins estimated that five years of statin treatment would prevent heart attacks, strokes and other major vascular events in:
* 100 of every 1,000 people who previously had a heart attack;
* 80 of every 1,000 people with angina or coronary artery disease;
* 70 of every 1,000 people with diabetes;
* 70 of every 1,000 people who have survived a stroke; and
* 70 of every 1,000 people with blocked arteries in their legs.
The benefits increased over the course of the study, Collins noted, and would be expected to continue to increase with longer treatment.
The trial was sponsored by the British Heart Foundation, the Medical Research council, Merck & Co. (which manufactures Zocor) and Roche Vitamins Ltd.