TUESDAY, March 8, 2005 (HealthDay News) -- Reducing "bad" cholesterol levels to new lows resulted in fewer problems, including heart attacks and strokes, in people with established coronary disease, a new study finds.
However, there was no commensurate decline in death rates.
The study appears in the April 7 issue of the New England Journal of Medicine, but was released Tuesday to coincide with a presentation at the American College of Cardiology's scientific sessions in Orlando, Fla.
Participants in the study took a high dose (80 milligrams) of atorvastatin, better known by its brand name Lipitor, a drug made by Pfizer, which also funded the study.
The results are not enough to warrant an all-out change of current cholesterol recommendations at this time, the study authors said.
"I don't think we ought to make a flat-footed recommendation based on one study," cautioned Dr. John LaRosa, lead author of the study and president of SUNY (State University of New York) Downstate Medical Center in New York City.
"It was good, but they didn't reduce total mortality, so we need to be a little cautious," agreed Dr. Bertram Pitt, author of an accompanying editorial in the journal and a professor of medicine at the University of Michigan Medical School.
While current guidelines recommend LDL levels of less than 100 mg per deciliter of blood for people with stable coronary heart disease, more recent data have suggested that levels less than 70 mg per deciliter might be better, the study authors said.
That previous research was not definitive, however. So the authors of the new study undertook a review involving 10,001 people with coronary heart disease who had LDL levels of less than 130 mg per deciliter.
The participants in the study were randomly assigned to receive either 10 milligrams or 80 milligrams of Lipitor a day and were followed for about five years.
Those who were treated with the higher level of Lipitor had mean LDL cholesterol levels of 77 mg per deciliter. Those treated with the lower dosage had mean levels of 101.
In the 80 milligram group, 434 patients (8.7 percent) had a heart attack, stroke or other event, compared with 548 patients (10.9 percent) in the low-dose group. That means there was an absolute reduction in the rate of major cardiovascular events of 2.2 percent and a relative reduction of 22 percent, the study authors said.
Although there were no differences in overall mortality, there was a slight increase in deaths not related to cardiovascular causes in the high-dose group, which is of potential concern, the study authors said.
Nevertheless, LaRosa felt the results were striking: Even if there was no reduction in mortality rates, there were other significant benefits, such as living without the disability of stroke.
"The most common cause of death in this study in both groups was not coronary disease," LaRosa said. "A few years ago, if you told me you had a treatment that would lower the death rate of coronary disease so that it was no longer the most common cause of death in people that had it, nobody would have believed it."
But it is the deaths not related to cardiovascular causes that has Pitt worried. "There are benefits, but is there any risk? That's a little uncertain," he said. "It's not clear-cut. People will have to look at it and decide."
It's also not clear if the lower cholesterol levels were related to Lipitor or would be seen with other statins as well. Other studies are ongoing, LaRosa said, and "within a year we'll at least be able to say that it applies to two statins or it doesn't."
"I don't even think it's a question of statins," he added. "I think it's probably a function of how low you can get the LDL, however you do that."
As for whether overall cholesterol policy should be changed, LaRosa noted that two other large studies addressing essentially the same question would be complete in about one year and may provide some answers.
"When you are going to make official national guidelines, you want to make sure you are standing on absolutely solid ground," LaRosa said.
All but one of the study authors acknowledged having received funds from Pfizer for research or being employed by the company. And all but one of the authors also acknowledged receiving fees and/or grants from numerous other pharmaceutical companies, including makers of other statin drugs.
The American Heart Association has more on cholesterol-lowering drugs.