A study published this week raises hopes that a common anti-cholesterol drug can reduce the artery deposits that play a crucial role in heart attacks and strokes.
How that translates into treatment isn't clear, and it doesn't mean you should eat more doughnuts. But the research provides further evidence that statins -- powerful anti-cholesterol drugs used for two decades -- can significantly improve the physical changes associated with heart disease.
Although doctors already prescribe statins to lower cholesterol and prevent the deposits -- known as plaques -- the study may encourage even more use, particularly at higher doses.
"We've never been able to get regression [of plaques] before," said Dr. Steven Nissen, the Cleveland Clinic cardiologist who led the study. "The drug produced an unexpectedly large benefit."
The results, appearing in Wednesday's issue of the Journal of the American Medical Association, were released at the annual meeting of the American College of Cardiology in Atlanta.
Known as the ASTEROID trial, the study examined 349 patients with heart disease from the United States, Canada, Europe and Australia. They received 40 milligrams a day of rosuvastatin, which is manufactured by AstraZeneca under the trade name Crestor. The dose is the highest approved by the Food and Drug Administration.
After two years, researchers measured each patient's "bad" cholesterol, or low-density lipoprotein; the "good" cholesterol, or high-density lipoprotein; and the volume of plaque in arteries around the heart.
On average, LDL declined by 53 percent, while HDL increased by 15 percent. More importantly, plaques shrank by 7 percent to 9 percent, a small but significant reversal.
"It's another feather in the cap for statins," said Dr. Mike Miller, director of the Preventative Cardiology Center at the University of Maryland Medical Center.
Nissen focused on the drug's ability to reduce plaque. In previous studies, other statins stopped plaque from increasing, but did not reverse the condition.
"If you really take cholesterol levels low, you can get plaque out of arteries," he said. He and others also emphasized Crestor's ability to lower LDL and raise HDL. In general, statins have done well at lowering bad cholesterol, but not at boosting good cholesterol.
First marketed in 2003, Crestor is the newest drug in the statin class. Others include ovastatin (Mevacor), pravastatin (Pravachol), simvastatin (Zocor) and atorvastatin (Lipitor).
AstraZeneca paid for the study, but Nissen said the arrangement had no effect on the outcome. He said his agreement with the company gave him the right to publish the results no matter the outcome. In the past, drug companies have sometimes tried to hide unflattering results.
Several researchers disputed the authors' claim that this was the first study to demonstrate plaque reduction. Patrick McBride, a University of Wisconsin cardiologist, said that during the past three decades, a variety of therapies -- including niacin, diet and exercise, as well as statins other than Crestor -- have decreased plaque.
"We already knew we could regress plaque," said McBride's colleague at Wisconsin, cardiologist James Stein. "This essentially tells us what we already knew."
Dr. Roger Blumenthal, a cardiologist with the Johns Hopkins University who wrote a JAMA editorial accompanying the study, said both sides were partly right.
Past studies did show regression of plaque in some patients, he said, but the Nissen study showed improvement in a larger proportion of patients -- 70 percent.
Blumenthal also said that the ultimate benefit of high-dose statin therapy is unclear. While the object of reducing plaque is to lower the risk of heart attacks and strokes, researchers don't know for sure whether that will happen. Several longer studies analyzing the effects of plaque reduction on heart attack, stroke and mortality are under way.
He emphasized that the study was not a green light for cheeseburger consumption -- diet and exercise are still crucial in fighting heart disease. "It's still the cornerstone. It's what all doctors need to keep recommending, probably more than anything else," he said.
Stein and others also criticized the ASTEROID study because it lacked a control group -- a set of patients who took a placebo or another heart disease drug. As a result, there is no way to know whether a similar dose of another statin, such as Lipitor, might do just as well.
"I expect we would have had the same results" with a high dose of another statin, Stein said.
AstraZeneca officials were thrilled with the study. "These are remarkable results," said Dr. Howard Hutchinson, the company's vice president for clinical studies. "This is the first time with a statin that shows we can reverse plaque."
Since its inception, Crestor has been a controversial drug. Some critics say it should be pulled off the market because it reportedly causes unnecessarily high rates of life-threatening muscle and kidney damage.
Dr. Sidney Wolfe, director of the watchdog group Public Citizen, said the drug is more dangerous than other statins, without offering unique benefits to offset the risk. He also noted that the study used the highest allowable dose, and expressed concern that it might encourage doctors to prescribe Crestor to more patients, and in larger quantities.
Nissen dismissed those concerns. He said his study subjects exhibited no sign of muscle or kidney problems, and said Crestor was no riskier than other statins.