Essentially, very little is known about the side effects of statins on healthy people, especially when used on a long-term basis. The only real clinical trial is going on right now, and the American people are the unwitting test subjects. That's not a new tactic, either: many prescription drugs aren't really tested until they're released. Then, if they cause enough problems and kill enough people, they're pulled off the market by the FDA.
So what's the reason for concern about statins? They're known to cause muscle weakness and pain. They cause mental confusion, painful tingling in the legs, and radical changes in mood. In fact, there's a long list of statin side effects that people should be aware of.
So what's the bottom line to all the statin prescribing going on these days? As one doctor in the article quoted here says, "We will look back in 50 years and say this is the period of time when we physicians sold out to the drug industry."