Cholesterol-Lowering Drugs and Muscle Damage
30 Oct 2009
Today millions of people are taking cholesterol-lowering drugs (CLDs) known as statins. But how safe is this medication, particularly if patients are complaining of muscle pain? Doctors often reassure patients that if blood tests are normal there’s no need to worry. But a recent report in the Canadian Medical Association Journal shows that blood tests cannot guarantee that muscle injury is not occurring.
Dr. Annette Draeger of the University of Berne, Switzerland, and her colleagues obtained biopsy samples from 83 patients. Of the 44 patients complaining of muscle pain 29 were talking a CLD and 15 had discontinued it for at least three weeks before biopsies were done. The study also included 19 patients who were taking A CLD and were free of muscle pain and a control group who had never taken a CLD.
The researchers noted that in the past muscle pain has normally been dismissed as a minor problem by both patients and doctors. But biopsies showed significant muscle injury in 57 percent of patients who complained of muscle pain. No muscle injury was present in those who had never taken a CLD.
Up to this point the American College of Cardiology and American heart Association recommend that CLDs should be continued as long as blood levels of, creatine phosphokinase, do not exceed 10 X the upper limit of normal. But only one patient who complained of muscle pain had an abnormal of creatine phosphokinase.
This report shows that even those patients suffering from muscle pain and who have normal levels of creatine phosphokinase can still have muscle injury. In fact, muscle injury was seen in one of 19 patients on long-term CLDs who reported as having no muscle pain!
Dr. Draeger reported that the severity of muscle damage was not correlated to the type of CLD being used or the duration of use or the dosage. However, none of the patients were taking doses over 80 milligrams a day. So it’s reasonable to speculate that if a low dose of CLD causes muscle injury these larger doses would cause increased muscle damage.
It was also admitted by DR. Draeger that there could be even more muscle injury than was reported? All biopsies were taken from the vastus lateralis muscle in the thigh ,regardless of where patients complained of pain. Again, it’s logical to assume that if biopsies were done in the painful muscle, the rate of injury would be higher.
There was another interesting finding. Researchers were surprised to find muscle injury in patients who had discontinued CLDs for a considerable time.
Dr. Richard H. Karas, of the Tufts New England Medical Center in Boston, said that these findings should not affect the clinical management of patients. Nor should it trigger alarm as the vast majority of patients taking CLDs do not suffer from muscle pain.
I don’t find this statement overly reassuring. It’s believed that about 10-15 percent of patients taking CLDs do complain of muscle pain, not an insignificant number considering the millions of patients taking CLDs. And it now appears that blood tests are not a reliable way to determine if muscle injury is taking place.
We also now that, in rare situations, CLDs can cause rhabdomyolosis, a potentially fatal condition, in which large amounts of muscle tissue is destroyed causing kidney failure. It’s a good reminder that patient’s are not taking M and M Candy.
Today a huge amount of information is available outlining the multiple benefits of CLDs. It’s therefore not the intention of this journalist to discount these potential advantages. Rather, to try and provide balance to what often appears to be an attempt to stress the benefits of CLDs and gloss over possible side-effects.
I must add that the vast majority of doctors are convinced that the advantages of CLDs far outweigh these potential complications. So a decision about taking a CLD is totally dependent on the advice of your own doctor. After all, one in five of us will die of heart attack, so decisions of this type cannot be taken lightly.
