The anxiously awaited results from the Heart Prevention Study (HPS) were finally published in the July 6 issue of Lancet.HPS, whose results were first presented at the November 2001 American Heart Association Scientific Sessions, is the largest study yet conducted examining the ability of statin drugs to reduce cardiovascular disease.
HPS enrolled 20,000 patients between the ages of 40 and 80 whose risk of heart disease was statistically high, but for whom there was little direct evidence that statins would be beneficial. That is, enrolled patients had no recognized indication to take statin drugs, either because they had no elevated cholesterol levels, and/or were women, elderly, or diabetics. These patients were randomized to receive either 40 mg of simvastatin daily (considered a high dose,) or placebo. Patients were then followed for an average of 5 1/2 years.
The results of HPS revealed several striking findings. Overall, the risk of heart attack and stroke had been reduced by one third in patients who received the statin. Furthermore, statins also significantly reduced the risk of developing angina, and the need for angioplasty, bypass surgery, and amputations. HPS showed, for the first time,that statins benefit women, patients over 70 years of age, and diabetics.
All 20,000 patients were monitored carefully for signs of muscle toxicity or liver toxicity, and no differences were found between those receiving statins and those receiving placebo - despite the high doses used. There was no evidence that patients suffered from cholesterol levels that were rendered "too low" by statins (a concern raised by prior, much smaller studies.) <o:p>
Because of the size of HPS and the design of the study, these results are statistically extremely powerful, and ought to change the way statins are used in the U.S. and around the world.
Essentially, as far as cholesterol levels are concerned, HPS says that if a patient has risk factors for cardiovascular disease (including family history, obesity, sedentary lifestyle, smoking, high blood pressure and/or diabetes) statins ought to be of benefit even if blood cholesterol levels are considered (by present standards) "acceptable."
Doctors and patients will need to get out of the mindset of measuring cholesterol levels and responding to those measurements. As investigator Rory Collins says, "Treat risk, not cholesterol." Patients with risk factors should now be receiving statin drugs.
What about the guidelines?
In May, 2001, the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults released new recommendations on who should be treated for elevated cholesterol and triglyceride levels. These new guidelines recommended a much more aggressive approach to cholesterol lowering than previous guidelines. Nonetheless, the HPS results blow these new guidelines (based on carefully measuring and responding to blood cholesterol levels) out of the water.
Based on the results of HPS, several members of the Expert Panel have publicly recognized the need to redo the guidelines. However, doing so is a political process that is likely to take years to accomplish. (The 2001 revision of the guidelines also took years to bring about.)
There is no reason for patients or their doctors to wait for a formal revision of guidelines. The data from HPS is compelling, and doctors should begin far more widespread usage of statin drugs immediately. Statins should be strongly considered in anybody who has cardiovascular disease or a high risk of cardiovascular disease.
Click here for a quick and easy explanation of how to assess your risk of coronary artery disease.
