"The importance of these findings is that they put the issue on the radar screen, so you can see if the risk is the same as in the general population," Karas said.
Another American study of statin side effects, about to be reported, finds that tendon problems are not common but do occur because the drugs impair the mitochondria, the energy-producing units of cells, said Dr. Beatrice Golomb, lead author of that study and an associate professor of medicine and of family and preventive medicine at the University of California at San Diego. This cellular impairment can also lead to muscle problems, she said.
It's impossible to give an overall number for incidence of the tendon problems linked to statin use because, "that depends on the dose of statins and the illness of the patient," Golomb said. "Older people with more medical problems tend to have more side effects."
"However you slice it, the tendon problems are less widely reported than muscle problems," she said.
Golomb and Karas differed on the importance of the adverse side effects of statins, which are among the most widely prescribed drugs in the world.
"I'm strongly in the camp that says there is overwhelming evidence that, overall, statins are safe and play an important role in our attempt to reduce heart attacks and stroke," Karas said. "The overall risk-benefit ratio is tilted strongly toward benefit."
But the balance of benefit over risk applies only "if you happen to be a middle-aged man with heart disease or at risk of heart disease," Golomb said. "For other groups, the risk outweighs the benefits."
There's more on cholesterol-lowering medicines at the American Heart Association.
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