Statins for Cardiovascular Disease: Truths, Myths, and Controversies

No group of medications is more controversial in my practice than the ‘statins.’ The statins or hydroxymethylglutaryl (HMG) CoA reductase inhibitors are a group of medications that are used to treat elevated cholesterol levels and lower risk of heart attack and stroke. They include medications like Crestor (rosuvastatin), Lipitor (atorvastatin), Zocor (simvastatin), and Pravachol (pravastatin) to name a few. They act to block the last step in cholesterol production in the liver and lower LDL by 30-60%.

Statins and the Liver
When statins were introduced in the 1990s, regular lab monitoring was recommended to screen for elevations in liver enzymes. The FDA changed the safety labeling after it became apparent that significant elevations in liver enzymes in patients taking statins are relatively rare (0.1%). Routine monitoring of liver function is no longer needed.

Statins and Muscle Pain & Injury
Statins can cause varying degrees of muscle pain and injury that occurs in approximately 4-8% of users. Symptoms can range from myalgia, which is characterized by mild muscle aches and soreness with normal muscle enzymes, to the severe condition known as rhabdomyolysis, which is a combination of kidney failure, very elevated muscle enzymes, and proteins in the urine.

Muscle injury is more likely to occur on higher doses of statin, with concurrent use of other cholesterol medications like Niaspan (niacin) or Zetia (ezetimibe), and in patients with conditions like ALS, hypothyroidism, or renal failure. The onset of muscle symptoms is usually within weeks to months of starting the statin, but may occur at any time. If muscle pain is experienced while taking a statin, an assessment for elevations in muscle enzymes, hypothyroidism, drug interactions, or low vitamin D can be performed. A decrease in dosage or a switch in the statin may be made if muscle enzyme levels are normal.

Statins and Vitamin D
Research is ongoing, but patients taking statins tend to have higher vitamin D levels. However, patients with low vitamin D are more likely to experience statin-related muscle pain. Thus, a vitamin D level should be measured prior to initiating a statin.

Statins and Coenzyme Q10
Coenzyme Q10 (CoQ10, ubiquinone) is an antioxidant that helps to make energy in the muscle cell. Research has been inconsistent on the matter, but some studies have found that statins decrease CoQ10 levels in the muscle and blood. It has been speculated that a reduction in CoQ10 levels in muscle may contribute to statin-induced muscle injury.

Some researchers have suggested that supplementation with ubiquinone or ubiquinol (a more expensive form) can reduce the risk of muscle aches. A meta-analysis of randomized trials concluded that existing trials do not suggest a benefit of CoQ10 for statin myopathy, but larger trials are needed to confirm this lack of benefit.

Statins and Diabetes
Statins have been associated with an increased risk of diabetes that is most significant with high-potency statins like Lipitor and Crestor. A 2016 analysis estimated that high-dose therapy would lead to 50 to 100 new cases of diabetes in 10,000 treated individuals. However, statins have been shown to reduce heart attacks and strokes in known diabetics. Both randomized trials and observational studies suggest that the benefits of statins on reduction of cardiovascular events outweigh the risk of development of diabetes in many.

Statins and Memory Loss
The FDA released a warning in 2012 after it compiled several reports it received through its Adverse Event Reporting System (AERS) of memory loss associated with statin use. Systematic reviews of randomized trials since that time have failed to find an association between statin use and memory loss; however, randomized trials may not detect rare medication side effects. In contrast to the reports above, several studies have even shown a reduced risk of dementia with statin use.

Statins and Cancer Risk
There is no evidence that statins increase or decrease risk for cancer.

Summary
In summary, the statins have had their fair share of controversies, but every medical intervention has risks and benefits. People who benefit most from statin use are patients who already have cardiovascular disease. This includes individuals who have had a heart attack, coronary artery stenting or bypass, angina, or stroke. I want to emphasize that treatment with statins is not about number goals. The ultimate goal of statin treatment is reduction in risk for cardiovascular events like heart attack or stroke, and prevention of death. I believe that the statins can greatly benefit certain high-risk patients and are invaluable drugs for anyone with cardiovascular disease.
By: Shanna Ndong