Understanding cholesterol drug research
Adhar Seth, MD, is a board-certified cardiologist on staff at Banner Estrella Medical Center. He can be reached at 623-433-0103.
Question: My primary care doctor recently told me that there is no benefit to using the cholesterol-lowering drugs simvastatin and ezetimibe (Vytorin) over simvastatin (Zocor). Should I stop taking the combination cholesterol medication?
Answer: Your primary care doctor was most likely referring to the results of a recent trial called ENHANCE. That trial studied patients with an inherited form of high cholesterol and compared the thickness of cholesterol plaque in the carotid arteries on the two different medications. Over a trial period of two years, no difference in the thickness of plaque between patients on either medication was found.
The trial did show that the cholesterol level in the patients taking simvastatin and ezetimibe was significantly lower. Most patients that are being treated for high cholesterol are being treated to lower their overall risk of future cardiovascular events. This is one reason why looking at the thickness of plaque in the carotid artery alone is not a good endpoint to evaluate, as was done in the ENHANCE study.
The ENHANCE study did not show any difference in cardiovascular outcomes between the two groups; however, the study was not large enough to make a meaningful conclusion regarding this matter. Larger trials are currently in progress to study cardiovascular events in patients taking simvastatin and ezetimibe, but the results will not be known for a few years.
The general feeling in the cardiology community is that the results of this one trial alone should not change a physician's prescribing patterns. In most cases, the lower your cholesterol, the lower your risk of cardiovascular events. I would recommend discussing with your primary care physician and your cardiologist before discontinuing or switching any cholesterol medications.