Do My Cholesterol Drugs Thin My Blood?

The short answer is YES, but very little.

Cholesterol lowering drugs, often called “statins” are intended to lower an important component of your total blood cholesterol, the LDL or “low density lipoproteins”.  An LDL below 100 is felt to be an important goal to reduce the chance of a heart attack or stroke. Millions of Americans in addition to making diet changes take these effective medications to decrease the production of LDL in the liver.  Those who have had a heart attack or stroke in the past and take statins actually live longer than those who don’t.

Over the years, we have learned that statin medications also do a number of other positive things to the body, unrelated to lowering LDL.  In addition to working on the inner lining of blood vessels and the heart muscle, the statins have been shown to modestly decrease the blood’s ability to clot.  Overall, this seems to be a beneficial side effect and does not appear to increase the risk of internal bleeding.  In fact, use of statins appears to decrease the risk of blood clots in the veins of the legs and perhaps the lungs as well.  On balance, this is a good thing.  Also good is that performing surgery on a patient who takes statins does not increase their bleeding risk.

However, statins should not be considered a substitute for the more powerful blood thinners that doctors often prescribe to reduce the stroke risk in those with irregular heartbeats or to help dissolve new blood clots in the veins of the legs, arms or lungs.  These drugs are specifically designed to prevent clotting and have no effect on LDL.  These blood thinners definitely need to be stopped several days before most types of surgery.