Statin drugs are commonly prescribed in the United States, primarily as treatment for high blood cholesterol levels. Left unchecked, high cholesterol (called hyperlipidemia) can lead to a variety of cardiovascular diseases such as hardening of the arteries (atherosclerosis), coronary artery disease, heart attack, or stroke. While statins are generally considered to be safe, there are some specific risks associated with the use of statins.
Statin Drugs
There are several drugs which fall into the category of "statin" drugs. Statin drugs are technically termed "HMG-CoA reductase inhibitors," which means they work by blocking part of the early biochemical cycle that leads to cholesterol production in the body. Some commonly used statins include atorvastatin (Lipitor), fluvastatin (Lescol), lovastatin (Mevacor), rosuvastatin (Crestor) and simvastatin (Zocor). At usual doses and in most patients, statin drugs are well tolerated. In patients with existing medical problems--especially kidney or liver problems, the risk of adverse events is increased.
Liver Cautions
Statins may impact the liver in some people. At initial to moderate doses, less than one percent of people who take a statin may experience an increase in certain liver enzyme levels. At higher doses, two to three percent of patients will have an increase in liver enzyme levels. These enzyme levels (for example, ALT or AST) are measures of liver function. An increase in the enzyme levels usually indicates that some type of liver impairment or damage is present. If liver enzyme elevation occurs, a downward dose adjustment of the statin is usually warranted, and sometimes the drug may be stopped altogether for a short period of time. Changing to a different statin drug may alleviate the enzyme level problem. If you are taking a statin drug, your prescribing provider should monitor your liver enzymes periodically during treatment to ensure that your liver function is normal while on the medication.
Muscle Cautions
Probably the best known of the dangers of statin drugs are the muscle problems that can happen when taking the medications. Simple muscle pains or soreness (myalgias) have been reported in one to six percent of patients in research studies of statin drugs. More complicated muscle pain and weakness (myopathy), accompanied by an elevated level of the muscle enzyme creatine kinase (CK), occurs in less than one percent of patients. The risk of this level of complication rises with increased statin drug doses, in patients with renal or liver impairment, and in older patients or those who are frail.
Rhabdomyolysis is the most significant complication of statin use. It is characterized by muscle pain or weakness, elevated CK levels, and elevated blood creatinine levels. In patients with severe muscle wasting due to statin use, as the muscle tissue breaks down, the components of muscle cells can block parts of the kidney, causing kidney damage. This complication is a rare but serious one.
Medication Interactions
Using certain other medications at the same time as statin drugs also increases the risk of myopathy and other complications. Cyclosporine, niacin, fibric acid drugs, macrolide antibiotics (like Zithromax), and some kinds of antifungals must be used with caution. Also, because alcohol impairs liver function, consuming alcohol when taking a statin drug can further burden the liver.
References
- Gerald K. McEvoy, Pharm.D., ed. 2009. AHFS Drug Information®. Bethesda, MD. American Society of Health-System Pharmacists, Inc.
- Pasternak RC, Smith SC, Bairey-Merz CN, et al. ACC/AHA/NHLBI clinical advisory on the use and safety of statins. J. Am. Coll. Cardiol. 2002;40(3):567-572.
