Statin myopathy: A common dilemma not reflected in clinical trials

■ ■ ABSTRACT Although statins are remarkably effective, they are still underprescribed because of concerns about muscle toxic- ity. We review the aspects of statin myopathy that are important to the primary care physician and provide a guide for evaluating patients on statins who present with muscle complaints. We outline the differential diagnosis, the risks and benefits of statin therapy in patients with possible toxicity, and the subsequent treatment options. ■ ■ KEY POINTS There is little consensus on the definition of statin-in- duced myopathy, and it is underdiagnosed. The incidence of statin-induced muscle toxicity in randomized con- trolled trials is lower than in clinical practice. Abnormal pharmacokinetic activity contributes to toxic- ity, but some patients may be predisposed by underlying metabolic muscle disorders. A focused history and neuromusculoskeletal examination are important in the evaluation of muscle complaints that may be induced by statins. In patients with possible statin-induced myopathy, assess- ing the risks and benefits of statin therapy is essential. For patients who cannot tolerate statin therapy, alternatives include a "statin holiday" followed by a rechallenge with a different statin, intermittent rosuvastatin (Crestor), or resin therapy. Sometimes the best alternative is a compromise be- tween the goal level for low-density-lipoprotein cholesterol and the level achievable with alternative therapy.