I have been thinking about the recent cholesterol management guidelines offered by the American Heart Association and American College of Cardiology experts (J. Am. Coll. Cardiol. 2013;doi:10.1016/j.jacc.2013.11.002) and how they affect my approach to my patients. I am quick to agree to the first three points and the end of LDL targeted therapy in the guidelines, which focus now on the intensity of statins therapy in patients who have already expressed the complications of atherosclerotic cardiovascular disease (ASCVD).
However, I do question a cardiovascular prevention program that, for low-risk individuals with an LDL cholesterol level above 190 mg/dL, is largely driven by statin therapy based on a risk prediction model using age, sex, hypertension, smoking, HDL, and LDL cholesterol elevation. Of all risk factors, smoking and LDL are the only ones that we can modify. Although we have made a major attack on smoking, it would seem that the key to survival is that all of us should take a statin.
There is an abundant source of data on the benefit of statin therapy in patients who have already expressed ASCVD. Although data are limited in regard to very-low-risk groups without evidence of ASCVD, a meta-analysis by the Cholesterol Treatment Trialist Collaborators indicates that the lowering of LDL cholesterol by 40 mg/dL results in an approximate 12% decrease in vascular mortality and 20% decrease in cardiac deaths, regardless of regardless of risk category (Lancet 2012;380;581-90). This benefit was observed even in low-risk individuals despite the slight excess risk of hemorrhagic strokes and diabetes.
The prediction model appears to be the major point of controversy. Along with thousands other Americans, I went to the AHA website to see what my risk score was. I found that by modifying a few factors I could move from less than a 7.5% risk of a stroke or a heart attack in the next 10 years to a risk of well over that. I was not reassured that I was in the company of more than 45 million fellow Americans. Critics of the risk model suggest that based on a number of epidemiologic surveys, the risk model may double the number of individuals to whom the prevention guidelines apply (Lancet 2013;382:1762-5). If we expand the population so broadly, are we going to be a society of statin pill poppers?
Our attempts in the last half-century to develop prevention therapy for hypertension and diabetes have only been marginally successful. The cardiorenal scourge of hypertension remains, despite a plethora of effective drugs that have had little effect on chronic renal disease. Although therapy for diabetes has been supremely effective in treating the acute and chronic metabolic aspects of diabetes, insulin therapy has not been successful in preventing the long-term expression of the cardiovascular, ophthalmic, and renal events. And now we are trying to assess the role of statins for the prevention of cardiovascular events.
In comparison to hypertension and diabetes, statin therapy has the potential to be a sea change in the prevention of ASCVD by lowering serum cholesterol and thereby limiting the growth of the atherosclerotic plaque. A number of clinical trials support the cardiovascular benefit of statin therapy and its effect on lowering serum cholesterol. Although it is clear that we need to reflect on the reliability of the current risk factor model, the current guidelines are an important step forward in the integration of statin therapy into the prevention of cardiovascular disease.
However, talking to patients and telling them that they have greater than a 7.5% risk of having a stroke or a heart attack in the next 10 years remains an abstract concept. The guideline committee now urges me to sit down with my patients and have a heart-to-heart talk about risk and how to decrease it by changing their dangerous lifestyles rather than taking statins for the rest of their lives. When it comes down to it, lifestyle change loses and statins win.
Dr. Goldstein, medical editor of Cardiology News, is professor of medicine at Wayne State University and division head emeritus of cardiovascular medicine at Henry Ford Hospital, both in Detroit. He is on data safety monitoring committees for the National Institutes of Health and several pharmaceutical companies.