"I threw the Simvastatin in the trash", my patient emphatically stated. "The nurse at the operating room for the ophthalmologist said that statin therapy for cholesterol is one of their top reasons for early cataracts (in younger people). That cataract surgery isn't something I want to duplicate."
How can these "wonder drugs" for lowering cholesterol and decreasing risks for heart attack, in people with known coronary disease, cause problems? How do physicians analyze the potential good and bad effects of prescription medication, including statins?
One way of considering medication effects relates to "benefits and harms", including the number needed to treat (NNT) and the number needed to harm (NNH). How many people need to take the drug for how long to prevent a major event or death in one patient? And, how many need to take it to cause a major event or death?
In the presence of known coronary artery disease, the NNT for Simvastatin is 64. It is estimated at 250 for those with no coronary disease. The NNH is 137 to make one diabetic, 1100 to make a cataract. A helpful article exploring these aspects of statin drugs from a blogger who reflects on an article about statins from Business Week is here. Another NNT comment about statins is in The NNT.
The NNT and NNH are useful concepts in making decisions about prescribing medications. More later.