A study of virtually the entire population of Sweden between the ages of 40 and 79 concluded that, despite a three-fold increase in the use of statin drugs to lower cholesterol , the statin drugs had no effect on overall rates of acute myocardial infarctions (heart attacks). The theory is that lowering cholesterol will lower the rate of heart disease, but, according to this massive study of almost 4 million Swedes, they had no effect. Here is the abstract, here is the full article (PDF), and here is an Internet news report about the study.
This is not new information. Two New York Times editorials have raised concern about over promoting cholesterol drugs in 2008 (here and here). And this video by Dr. Malcolm Kendrick shows that high cholesterol does not cause heart attacks. Read all about the debunking of the lipid hypothesis in Good Calories, Bad Calories by Gary Taubes.