Statin-Induced Myopathy

Statins inhibit the synthesis of cholesterol and promote the production of low density lipoprotein (LDL)-binding receptors in the liver resulting in an unusually marked decrease in the level of LDL, and a modest increase in the level of high density lipoprotein (HDL) circulating in blood plasma. Therefore, statin drugs are the primary pharmacologic treatment for hypercholesterolemia and coronary artery disease worldwide.

Despite their demonstrated safety and efficacy, 25% to 50% of individuals with cardiovascular disease are nonadherent with statin medications after one year. Although there may be multiple contributing factors, many experts report that a contributor to statin nonadherence is associated with side effects, including skeletal muscle toxicity due to poor or compromised metabolism of statin drugs.

Statin-induced myopathy has been associated with SLCO1B1 gene variant NM_006446.4:c.521T>C (rs4149056). The risk of myopathy may be substantially increased in patients who take 80 mg of simvastatin daily, as well as in those who are also receiving certain other drugs.

 

> Ordering information for targeted mutation analysis

 

Indications for genetic testing:

  1. Risk assessment for developing statin-induced myopathy
  2. Optimizing the statin dose

 

References:

Ramsey LB et al. The clinical pharmacogenetics implementation consortium guideline for SLCO1B1 and simvastatin-induced myopathy: 2014 update. Clin Pharmacol Ther. 2014 Oct;96(4):423-8.
EARCH Collaborative Group et al. SLCO1B1 variants and statin-induced myopathy–a genomewide study. N Engl J Med. 2008 Aug 21;359(8):789-99
Tomaszewski M et al. Statin-induced myopathies. Pharmacol Rep. 2011;63(4):859-66.