Docs look at new sign of heart disease risk
Clinical trial to study how drugs affect CRP levels
By Debra Goldschmidt
CHICAGO, Illinois (CNN) -- Scientists are launching a trial to determine if drugs used to lower cholesterol, called statins, could also lower the levels of c-reactive proteins (CRP), an indicator of risk for heart disease.
CRP levels are measured by a simple blood test and provide doctors with a measurement of how much inflammation is in the body, thus providing a clearer picture of who is at risk of suffering a heart attack or stroke as far as 15 to 20 years in the future.
Dr. Paul Ridker of Brigham and Women's Hospital in Boston announced the clinical trial at the American Heart Association conference in Chicago and is the primary investigator for the study, which plans to enroll patients in the mid- to late spring of 2003.
The study hopes to follow 15,000 patients for three to four years. Ridker said the study will comprise men over 55 and women over 65 who have no evidence of heart disease.
All study participants must have an LDL, or "bad cholesterol" level, of less than 130 and a CRP level of less than two. Patients in the multi-site, randomized study will not know whether they are taking a placebo or the drug rosuvastatin.
Rosuvastatin is made by AstraZeneca and received approval this month for use in the Netherlands. It has not been approved for use in the United States. The U.S. Food and Drug Administration is overseeing the clinical trial, which is being sponsored by the drugmaker.
Ridker said the sample of patients will be representative of the approximately 25 to 30 million Americans who have low LDL and high CRP.
The announcement comes a few days after Ridker's research on the importance of CRP in predicting who is at risk for heart disease was published in the New England Journal of Medicine. Some have called that study the strongest case yet for measuring CRP levels in addition to cholesterol in patients.
Doctors seem convinced of the importance of CRP as an added risk factor, but they have been scratching their heads over who should be checked. The American Heart Association and the U.S. Centers for Disease Control and Prevention are working on guidelines to answer that question.
Dr. Thomas Pearson, who spoke on behalf of the joint effort, said each group has drafted but not approved recommendations. They are expected to be issued in December.
In the meantime, heart association spokesman Dr. Sid Smith said, the question of who should be tested could not be answered because the group does not have guidelines on CRP.
"When we have new information we need to evaluate it very carefully before making recommendations to physicians and to the public about how to deal with this new information because you don't want to make a strong recommendation now, only to get new information in the future that may suggest that the initial recommendation was not correct," Dr. Robert Bonow, president of the American Heart Association, cautioned. He said more research is needed even while all research on CRP is being reviewed.
Dr. Richard Paternak, who moderated the panel on inflammation at the conference, pointed out that the test (for CRP) won't do any good if it won't improve the outcome of the patient. He emphasized that it is not known what to do with patients who have high CRP levels.
Ridker pointed out, "we already know that diet, exercise and smoking cessation reduce event rates. That's true of people with people with low and high cholesterol levels, and that's true of people with low and high CRP levels." He said people with high CRP have the chance to make lifestyle changes to lower their risks in the future.
Previous research done by Ridker on a small scale looked at several other cholesterol-lowering medications and found that statins help lower CRP. Ridker said he hopes the study helps obtain what he calls "hard evidence that statins are effective in this group," referring to the millions with low cholesterol and high CRP.