study published online early in Archives of Internal Medicine, the authors analyzed data from the infamous Women's Health Initiative consisting of 153,840 post-menopausal women without diabetes at baseline, of whom just over 7% were taking a statin. After 7-12yrs of follow up, those women who were already taking a statin had a 50% greater relative risk of developing diabetes than those women who were not taking a statin. In absolute terms, those women taking a statin had a 9.93% risk of developing diabetes while those who were not taking a statin had only a 6.41% risk.
meta-analysis of 5 statin trials published last summer in JAMA also demonstrated an increase risk of developing diabetes in those randomized to high dose statins compared to moderate dose. And almost 2 years ago now, a meta-analysis of 13 statin trials published in Lancet also noted a slightly increased risk of developing diabetes.
So is this the death knell for statins? Absolutely not! As has been reported over the years and summarized nicely in another meta-analysis of 14 statin trials published 4yrs ago in Lancet, the benefit of cardiovascular risk reduction in absolute numbers far outweighs the much smaller risk of developing diabetes. However, because the risk is real, we can't go about putting statins in the water but instead, must develop clearer guidelines as to who stands to benefit most while being harmed least. Remember that all medications, no matter how miraculous, are truly double-edged swords and can be harmful when used incorrectly, whether that be allergy, dose, indication, or interaction. One last thought: none of these studies were designed as randomized double blind placebo controlled trials to specifically look for causation. As it stands, the evidence is only associative. But it's surely damning . . .