Semantics always seem to play a role in science. How a written statement is made, in research for example, is certainly well thought out prior to a publication. As my friend Dr. Mark Stengler pointed out recently in his article entitled The Cholesterol Study You Never Heard About, the researchers writing in JAMA Internal Medicine analyzed 21 clinical trials that examined the effectiveness of statin drugs in reducing death in the people taking them. Here is where semantics comes in. Dr. Stengler states, “The absolute risk for reducing all-cause mortality was 0.8%, heart attack was 1.3%, and stroke was 0.4% compared to control groups. In other words, there was a weak association between reducing LDL-cholesterol with statin drugs and preventing cardiovascular problems and death.” Yet, millions of Americans take them. Side effects are yet another story but will be covered in future blogs.
Absolute vs Relative Risk
Stengler continued, “The paper I am citing was investigating relative risk reduction and absolute relative risk reduction. In practical terms, if treatment with statins reduces the risk of an event such as a heart attack from 1 percent to 0.5 percent, the relative risk reduction is 50 percent. However, the absolute risk reduction would be 0.5 percent. This means that 200 people would need statin treatment to avoid one heart attack event.” Understand that the other 199 people are not benefitting at all by taking them based on their absolute risk. “The relative risk shows tremendous benefits of taking statin drugs however the reported absolute risk shows an entirely different story. I hope your doctor knows the difference.