Feb. 17, 2010 -- The popular class of cholesterol-lowering drugs called statins may slightly raise the risk of type 2 diabetes, but experts say the benefits of these potentially lifesaving drugs far outweigh the risks.
A new review of 13 studies on statins and their side effects with a total of more than 91,140 participants found use of statins increased the risk of type 2 diabetes by 9%. This risk was found primarily among older people; there was no additional diabetes risk among statin users 60 and under.
Researchers stress that this study does not prove that statins directly raise the risk of diabetes, but it raises the possibility of either a direct or indirect link between statins and diabetes that merits further investigation. They say the absolute risk of developing diabetes as a side effect of statin use is still small, especially compared to the much larger beneficial effect that statins have on reducing the risk of heart attack and other complications of heart disease.
To put the results into context, researchers say treatment of 255 people with statins for four years would be associated with one extra case of type 2 diabetes. But statin treatment in the same 255 individuals for four years would prevent five major heart-related events, including heart attack or death due to heart disease.
Researcher Naveed Sattar of the University of Glasgow, Scotland, and colleagues say studies on statin therapy have often produced conflicting results in regard to the risk of developing type 2 diabetes.
To clarify these conflicting results, researchers compared the results of 13 published and unpublished studies on statins and diabetes conducted between 1994 and 2009. Each study involved at least 1,000 participants and followed them for more than one year.
Of the 91,140 total participants in the studies, 2,226 of those on statins and 2,052 of those who didn't take the drugs developed type 2 diabetes over an average of four years.
Overall, stain use was associated with a 9% increased risk for diabetes across the 13 studies, but further analysis showed this risk was primarily among older adults.
Researchers write that the results of their review should not change the recommendation for use of statins among those at moderate or high risk of heart disease, but the potential for diabetes risk should be taken into account if statin therapy is considered for people at low risk for heart disease.
In an editorial that accompanies the study, published in The Lancet, Christopher P. Cannon of Brigham and Women's Hospital and Harvard Medical School in Boston writes that this risk does merit monitoring but should not change the current use of statins in cholesterol-lowering therapy.
"The benefit in preventing total vascular events to the risk of diabetes is a ratio of about 9:1 in favour of the cardiovascular benefit -- the benefit seems to greatly outweigh the risk," writes Cannon. "Whilst a new risk of statins has been identified, the risk seems small and far outweighed by the benefits of this life-saving class of drugs."