How Many People Can’t Tolerate Statins?

A: Yes. Studies show that about 5 to 10 percent of people are unable to tolerate statins, largely because of muscle aches and related side effects, including potential muscle damage. But many people who have been labeled intolerant to the drugs probably are not, and medical researchers, normally a genteel lot, disagree sharply on the extent to which side effects are a problem.

Proponents of statins argue that concerns about safety have been overblown, with some even describing the research on side effects as “fraudulent.” Opponents maintain that the concerns are real. Both sides agree that the debate is important, since a patient who has been inappropriately prescribed a statin risks muscle damage. But a patient who has been inappropriately denied a statin risks heart attack.

Statins can cause a spectrum of muscle symptoms. Muscle aches, known medically as myalgias, constitute the greatest number of muscle complaints and the greatest area of controversy. More serious muscle problems, on the other hand, are not controversial, since they are a clear contraindication to treatment with the drugs.

The psychology of myalgias involves the nocebo effect, the flip side of the placebo effect. Whereas a placebo is an inert substance that exerts a beneficial effect, a nocebo is an inert substance that exerts an unpleasant effect.

The Effect of Statins on Skeletal Muscle Function and Performance (STOMP) trial examined the issue of muscle symptoms directly. STOMP studied 420 patients who had never received statins. About 5 percent developed myalgias while taking the statin atorvastatin (brand name Lipitor), and about half that many developed myalgias while taking placebo, or more precisely, nocebo.

The GAUSS-3 trial examined the question from another angle. GAUSS-3 studied 491 patients who had been labeled intolerant to at least two different statins. Surprisingly, more than half of these previously intolerant patients were able to tolerate low-dose atorvastatin. While the rest developed myalgias on atorvastatin, half as many also developed myalgias on placebo.

The key for patients who have muscle symptoms while on statins lies in a blood test known as creatine kinase, or CK, an enzyme found in muscles. High levels of the enzyme indicate muscle damage.

If muscle damage is present, alternatives to statins should be used. If muscle damage is not present, temporarily discontinuing statins — in what doctors call a “drug holiday” — and restarting at a lower dose may be tried. Alternatively, many people who are intolerant of one statin may find that they are able to take a different statin without difficulty.

Diet, exercise and many other options are also available for people who are ultimately unable to tolerate statins. The only mistake would be to allow dangerously elevated cholesterol to go untreated.