The results of the JUPITER trial, published in an online version of the New England Journal of Medicine, have created a near frenzy in the media and among cardiologists.

In the trial, 17,802 men and women were randomly assigned to take either a placebo or rosuvastatin (Crestor) 20 mg daily for an average of 1.9 years. The average age of the participants was 66 years and they had no history of coronary heart disease (CHD) or other manifestations of atherosclerosis (a build-up of plaque in the inner linings of arteries that causes progressive narrowing and hardening of those arteries over time).

Subjects were entered in the trial because they had elevated blood levels of C-reactive protein (CRP), a marker of inflammation in the body, rather than for high LDL ("bad") cholesterol. In fact, the median starting LDL cholesterol was so low (108 mg/dL) that few of these participants would have qualified for cholesterol-lowering medications under the present guidelines—especially since their median levels of HDL ("good") cholesterol (49 mg/dL) and triglycerides (118 mg/dL) were not abnormal.

On average, other risk factors for CHD were not prominent in study participants, although they were generally overweight or obese (average body mass index of 28.3) and 41 percent met the criteria for metabolic syndrome, which is associated with an increased risk of CHD and diabetes.

In those taking rosuvastatin, the median LDL cholesterol fell to 55 mg/dL and, compared to the placebo group, they had a relative reduction of about 50 percent in the number of heart attacks, fatal and nonfatal strokes, and the need for arterial revascularization procedures, such as angioplasty or bypass grafts. (If this seems like an awful lot of heart trouble cropping up in just 1.9 years, remember that the Jupiter study included a large number of participants and they were all positive for a marker of CHD.)

The statin was well tolerated, but there was an unexpected, highly significant increase in the incidence of diabetes among those taking the drug.

The results of JUPITER raise a number of questions, most importantly

• Who should be screened for the C-reactive protein marker?
• When should statin therapy be started in men and women with few other risk factors?

The National Heart, Lung and Blood Institute has asked a panel of experts to review this and other recent studies on CRP as a marker and then to consider possible modifications in the present guidelines for how to use risk factors in making therapeutic decisions.

For the present, it makes sense to me to add a CRP test, or possibly a test for coronary calcium instead, in those individuals who are at intermediate risk (one risk factor such as high blood pressure, positive family history, cigarette smoker), even if their LDL cholesterol is within a good range. Statin treatment could then be justified if either test is abnormal.

However, I am hesitant to automatically recommend statin treatment in those who have a high CRP, because of the fact that excess fat tissue and weight can also raise CRP levels. The peace of mind derived from taking a daily statin pill would make it harder for a person to lose weight by eating less and exercising more, thus increasing the person's chances of diabetes.

Before putting statins in the drinking water, it is also important to keep in mind that the statin group only had an extremely impressive reduction in relative risk—the relative risk of a cardiovascular event in just the group receiving the statin, compared with the risk of the group not receiving it. A more important consideration is the effect of the statin treatment on participants' absolute risk of having a cardiovascular event—that's the chance that a person will develop a cardiovascular event over a specified time period. Since these participants were rather healthy, their improvement in terms of their absolute risk is less impressive: Only about 1 in 100 was helped by taking a statin for almost 2 years.

More widespread statin treatment of "healthy" people would raise costs and, potentially, cause side effects without encouraging participants to attain the weight loss necessary for preventing the development of type 2 diabetes.