Muscle Damage From Statins May Evade Blood Test
Normal CPK Test Doesn't Rule Out Muscle Injury
Serious Statin Injury Is Rare continued...
”Patients on statin therapy who are feeling fine should not worry about muscle damage, and no one should stop treatment without talking to their doctor,” he says.
The finding that CPK testing can confirm, but not rule out, statin-related muscle injury comes as no surprise to cardiologist Sidney C. Smith, Jr., MD, who is a past president of the American Heart Association. He tells WebMD that several smaller studies have shown the same thing.
Smith is a professor of medicine at the University of North Carolina at Chapel Hill.
“This is not a new, but it is important research,” he says. “And it is important to point out that we are talking about a minority of a minority of patients taking statins.”
Taking a Break From Statins
Karas and Smith say patients with CPK levels in the normal range should be taken off statins for a time if they experience persistent, unexplained muscle pain.
“If the muscle pain goes away after four to six weeks, that is a pretty good indication that it was treatment related,” Smith says.
He adds that patients who experience muscle pain on one statin may have no muscle pain on another, or the pain may disappear with lower dosages of the drug.
Cardiologist Robert Bonow, MD, who is also an AHA past president, points out that in patients who have had a heart attack or stroke, the risks of stopping treatment may outweigh the benefits.
“In these patients lowering cholesterol is very important,” he says.
In a written statement, a spokesperson for Lipitor manufacturer Pfizer Inc. tells WebMD that patients taking a statin should always report any unexplained muscle pain, tenderness, or weakness to their doctor.
“The incidence of muscle injury in the absence of elevated CPK levels in patients treated with Lipitor has not been determined,” writes Sally Beatty of Pfizer.