Skeletal muscle ultrastructure and function in statin-tolerant individuals.

INTRODUCTION

Statins have well-known benefits on cardiovascular mortality, though up to 15% of patients experience side effects. With guidelines from the American Heart Association, American College of Cardiology, and American Diabetes Association expected to double the number of statin users, the overall incidence of myalgia and myopathy will increase.

METHODS

We evaluated skeletal muscle structure and contractile function at the molecular, cellular, and whole tissue levels in 12 statin tolerant and 12 control subjects.

RESULTS

Myosin isoform expression, fiber type distributions, single fiber maximal Ca(2+) -activated tension, and whole muscle contractile force were similar between groups. No differences were observed in myosin-actin cross-bridge kinetics in myosin heavy chain I or IIA fibers.

CONCLUSIONS

We found no evidence for statin-induced changes in muscle morphology at the molecular, cellular, or whole tissue levels. Collectively, our data show that chronic statin therapy in healthy asymptomatic individuals does not promote deleterious myofilament structural or functional adaptations.