In November, the American College of Cardiology and the American Heart Association released new guidelines for the treatment of high cholesterol. The recommendations fundamentally change the way we will manage high cholesterol in people with established heart or vascular disease or in those who are at highest risk for getting it. As a result of the new guidelines, people taking non-statin drugs may be encouraged to change their medication. To understand how this change came about, it helps to know the history of cholesterol-lowering medications.
For years, we've known that a low-fat diet, regular exercise, a healthy weight, tobacco avoidance, and aggressive control of blood pressure and diabetes significantly lower the risk of plaque build-up in the arteries, which in turn lowers the risk of heart attack, stroke, amputation, and other serious heart and blood vessel problems. Researchers also discovered that LDL (bad) cholesterol leads to hardening of the arteries and that HDL (good) cholesterol actually protects against this condition. After that discovery, the pharmaceutical industry began looking for drugs to lower LDL or raise HDL levels.
Early on, the goal of research in this field was to find drugs that reverse hardening of the arteries. Researchers found many drugs that improved blood cholesterol levels, but frustratingly, they did not reduce plaque build-up or lower the risk of heart attack, stroke, amputation, etc. They even conducted trials of antioxidants such as Vitamin E but found they did not reduce the risk of heart or blood vessel events either.
This changed in the early 1990s with the publication of the landmark 4S Trial (Scandinavian Simvastatin Survival Study). This trial also began as a plaque-reducing trial. Interestingly, it did not demonstrate any significant reduction in the amount of plaque in the arteries of the heart, but there was a dramatic reduction in the rate of death, heart attack, stroke and the need for procedures such as bypass and angioplasty. How could this discrepancy be explained?
The answer appears to be that it's not just that LDL cholesterol needs to be lowered, it's how it is lowered that makes a difference in outcomes. Statin drugs appear to have the unique effect of stabilizing plaque in the arteries, making it less likely to experience plaque rupture which leads to serious cardiovascular problems like heart attacks or strokes. This effect appears to be conferred by the entire statin class of drugs. Other drug classes - bile acid sequestrants, fenofibrates, niacin, ezetimibe, fish oils, etc. - have not been shown to reduce the risk for experiencing these severe cardiovascular problems, despite improving the cholesterol levels in the blood.
With this new information, doctors may take patients off of other drug classes and switch them to statin drugs. In addition, the new guidelines do not recommend that people be treated to reach specific LDL target goals - only that people take an appropriate dose of statin medications. The guidelines are based on extensive medical literature from many high-quality medical trials. They entail proven strategies for lowering the risk of major adverse cardiovascular events and may ultimately save many lives.
If you are taking cholesterol-lowering drugs, talk to your doctor or cardiologist about the new guidelines and which medication is best for you.
About the Author:
Randy Bottner, M.D., FACC, is a cardiologist at Savannah Cardiology. He can be reached at 912-352-8700.