statin drugs cause diabetes

Statin drugs definitely cause diabetes

Statin drugs are the probably most successful drugs of all time, and are being recommended for many conditions beyond high cholesterol and artery disease - usually following some small change when data from studies is dredged or combined - this type of analysis can usually achieve any answer the researcher is seeking and needs to be considered with great caution - especially when there is a downside to the therapy.   For a while people were considering adding a statin drug to a 'polypill' to be taken by everyone over the age of 45 - 50 years. (The polypill was to contain a statin, ACE inhibitor, beta blocker, aspirin and folic acid).  But the adverse effects of statins on muscles, brain and nerves, liver, and other organs are becoming increasingly appreciated.   Many of the trials with statins started after a run in phase where people were on statins, but if they had significant side effects, they did not enter the trials. 

NOW we have proof that statins cause a major increase in the development of diabetes (almost doubles the risk), in a well researched trial from Germany (click here for full article). They followed 8,749 non diabetic people for almost 6 years.  625 developed diabetes and those on statin drugs had a 46% increase in diabetes compared to those not on statins (Fig 1).

  The dose of statin also made a difference (fig 2). 
So statins reduce the risk of heart attack and death, but double the risk of diabetes.  Where does this put us now?
First - medicine is always balancing the risk vs the benefits of treatment, and there seems little doubt in people who have definite heart disease ( heart attack, coronary disease, angioplasty, bypass surgery) statins do reduce the risk of further events and should be recommended.  However if there is a risk of diabetes, then only a low dose of the statin drugs should be used.
However in primary prevention, and especially in women, where the risks are small and evidence of absolute benefit is not very strong - many people, including me, are suggesting caution unless the cholesterol is exceptionally high or there is a very strong family history.   (In these people, I would probably recommend a coronary calcium scan before starting them on statin drugs.)  If there is a risk of diabetes, then possibly Pravastatin would be the best one to use.  In the West of Scotland Study (WOSCOPS), using this drug in primary prevention, there was actually a reduction in diabetes in those taking the drug.   There were too few in this recent German Study on Pravastatin to reach any answers.