You're not the only one who is confused by the new guidelines for the use of statin drugs. Here's the background: on November 12, 2013 the American Heart Association and American College of Cardiology unveiled new recommendations for the use of these cholesterol-lowering agents, based on a four-year review of evidence on what works best to prevent heart disease and stroke. They depart dramatically from the way statins have been used in the past.
Until now, the reason to take statins drugs was to get LDL cholesterol down below 100 (preferably to 70) as measured by regular blood tests. The new guidelines dispense with that goal and call for prescribing a statin dose that lowers a patient's risk of heart disease and stroke in combination with lifestyle measures such as regular exercise, weight control and a diet rich in fruits, vegetables, whole grains, low-fat dairy, legumes, fish, poultry, and nuts and low in sweets, sugar-sweetened beverages, and red meats, similar to the Mediterranean and DASH diets.
Instead of prescribing statins for patients with high LDL cholesterol, the new guidelines call for using the drugs to treat two groups of people at increased risk of heart attack or stroke: (1) patients who have diabetes or have had a heart attack and (2) people with very high levels of LDL, 190 or above. Beyond that, the guidelines call upon doctors to evaluate other patients on the basis of their risk of heart attack or stroke over the next decade as determined by calculations that factor in age, gender, total and HDL ("good") cholesterol, systolic (top number) blood pressure, blood pressure treatment, diabetes, smoking and the risk of stroke. If that calculation doesn't lead to a clear-cut decision, the new guidelines suggest that doctors also take into account any family history of premature heart disease in a first-degree relative, high-sensitivity C-reactive protein, coronary artery calcium scoring and ankle-brachial index (a test to check the risk of peripheral artery disease).
Because statins don't necessarily reduce LDL cholesterol to what have been regarded as desirable levels, doctors also prescribed other drugs such as ezetimibe (Zetia). However, studies have shown that while ezetimibe does reduce LDL, its use does not lower the risk of cardiovascular disease or death. We know that statins lower the risk of heart attack and stroke, but the guidelines committee found no evidence that lowering LDL to specific goals makes any difference. So far, no study has determined that risks of cardiovascular disease are lower with low LDL numbers.
Some of the comments I've seen from cardiologists suggest that the guidelines aren't going to change treatment practices much, and that many doctors will continue to encourage patients to strive for low LDL numbers. The new guidelines are simply to help health care practitioners make decisions about stains based on the evidence of their effectiveness in certain patient populations over time. If you have concerns about whether or not you personally should be on statins, discuss them with your physician.
Andrew Weil, M.D.
Neil J. Stone 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 Task Force on Practice Guidelines, Journal of the American College of Cardiology, doi:10.1016/j.jacc.2013.11.002