If you have elevated cholesterol levels, the decision you and your doctor will make regarding treatment ought to be based on the 2013 guidelines from the American Heart Association and the American College of Cardiology, under the auspices of the National Heart, Lung, and Blood Institute (NHLBI).
The first step in following the 2013 guidelines is to decide whether you need to be treated at all. This is done by carrying out a full assessment of your cardiac risk. This assessment includes, of course, measuring your LDL cholesterol level – but it also includes a comprehensive evaluation of all your cardiac risk factors.
The decision of whether or not you need to be treated will solely depend on your overall cardiac risk – whether or not your cholesterol levels are actually elevated.
What Is Your Risk Category?
The NHLBI guidelines assign elevated cardiac risk to one of four high-risk categories. (People whose risk is not elevated can consider themselves to be in “Category 5,” and they do not need to worry about treatment – other than to manage their cardiac risk factors, to help assure they will remain in this low-risk category.)
Category 1: People who have known cardiovascular disease due to atherosclerosis. Most of these people will have had a myocardial infarction (heart attack), angina, peripheral artery disease, or a stroke.
Category 2: People who have very high LDL cholesterol levels - greater than 189 mg/dL. In most cases these are people with familial hypercholesterolemia.
Category 3: People with diabetes who are 40 to 75 years old, and who are not in Categories 1 or 2.
Category 4: People whose 10-year risk of developing cardiovascular disease due to atherosclerosis is estimated to be 7.5% or higher. (The NHLBI has provided this simple on-line tool to estimate your 10-year risk.)
What Treatment is Recommended?
In a marked departure from prior cholesterol treatment guidelines, the new cholesterol guidelines do not recommend treating to specific cholesterol target values. Instead, they emphasize treating to reduce cardiac risk to the fullest extent possible.
The treatment is essentially twofold. First, of course, any and all measures to improve your cardiovascular lifestyle ought to be aggressively undertaken. These measures include weight control, smoking cessation, getting enough exercise, eating a heart-friendly diet, and controlling blood pressure and diabetes. Such lifestyle measures are important for everyone – whether or not you currently fit into one of the four high-risk categories. But they are critically important for people who are at elevated risk.
Second, if you are in any of these four categories you should take a statin drug. People in Categories 1 and 2 should be given high-intensity statin therapy - such as rosuvastatin (Crestor) 20 to 40 mg per day, or atorvastatin (Lipitor) 80 mg per day. People in Categories 3 and 4 can be given either high-intensity or moderate-intensity statin therapy (moderate intensity being roughly half the high-intensity dose).
Strikingly, only statins are recommended under the 2013 guidelines. Just as the guidelines no longer make a recommendation of treating cholesterol levels to a specific target, neither do they make mention of using any of the non-statin cholesterol-lowering drugs – such as ezetimibe (Zetia, Vitorin), niacin, bile acid resins, or fibrates – to achieve a target level.
The reason statins are recommended, and other cholesterol-lowering drugs are not, is simple. The goal of the new guidelines is to reduce cardiac risk. And of the cholesterol-lowering drugs, only the statins have been shown to lower the incidence of cardiovascular events such as heart attack, stroke and death. In fact, several clinical trials with non-statin drugs appear to have shown a trend toward worse outcomes, despite the fact that cholesterol levels were reduced.
The risk-reducing properties of statins may or may not be related to their cholesterol-lowering abilities. The fact is that statins seem to lower cardiac risk in several different ways. It may even be best to think of statins not primarily as cholesterol-reducing drugs, but rather as risk-reducing drugs that also happen to lower cholesterol levels.
The NHLBI guidelines for treating cholesterol now deemphasize treating cholesterol levels to some target value, and instead emphasize reducing cardiac risk to the fullest extent possible for those people whose cardiac risk is very high. The guidelines urge lifestyle modification and the use of statin drugs to achieve this end.
Stone NJ, Robinson J, Lichtenstein AH, et al. 2013 ACC/AHA guideline on the treatment of blood cholesterol to reduce atherosclerotic cardiovascular risk in adults: A report of the American College of Cardiology/American Heart Association. J Am Coll Cardiol 2013.Hayward, RA, Krumholz, HM, Zulman, DM, et al. Optimizing statin treatment for primary prevention of coronary artery disease. Ann Intern Med 2010; 152:69.
Rosenson, RS, Lloyd-Jones, D. A critical appraisal of revised cholesterol guidelines for the very high-risk patient. Expert Rev Cardiovasc Ther 2005; 3:173.