More Potent the Statin, higher Risk of Diabetes in elderly, finds Canadian study
The benefit of statins in preventing cardiovascular disease has been well established for years. So has the link between diabetes and cardiovascular disease. Thus, it came as somewhat of a surprise when the 2008 JUPITER trial revealed that the use of rosuvastatin—the most potent of the statins—was associated with a small but still statistically significant increase in hemoglobin A1c and onset of diabetes. On the other hand, the West of Scotland Coronary Prevention Study concluded that the use of pravastatin—a less potent statin—decreased the risk of diabetes by 30% versus placebo.
An Ontario, Canada study released this week aimed to clarify the possible interplay between diabetes and different statins, looking at the potential role relative potency. The population-based retrospective cohort study, published in the May 23th issue of the British Medical Journal, reviewed the charts of 1.5 million people age 66 and older who were started on a statin anytime from August 1997 to March 2010.
Recall that cohort studies are those that identify subjects who have been exposed to an established or potential risk factor (including exposure to a medication) and are then followed for the onset of disease. Cohort studies are considered the most robust type of observational study. However, on the flip side, the presence of confounding variables can skew the results and lead to false conclusions. The authors acknowledged that the contribution of pre-established risk factors for diabetes such as weight, ethnicity, and family history were not accounted for in their work.
In true Knowmedge style, its results are presented in audiovisual fashion below:
In summary, the population based study found that compared to pravastatin, higher potency statins—namely atorvastatin and simvastatin—may be associated with an increased risk of developing a new diagnosis of diabetes. Rosuvastatin’s apparent increased risk became non-significant when dose was incorporated. Don’t expect simvastatin or atorvastatin (which went off patent in late 2011) to stop being prescribed anytime soon. However patients at a higher risk of developing diabetes may be well-served to be initially considered for pravastatin, fluvastatin or lovastatin instead for their lipid control and cardiovascular event reduction.
Reference BMJ 2013; 346 doi: http://dx.doi.org/10.1136/bmj.f880 (Published 19 March 2013)