LOGIC March 2018 Vol 17 Vol 1 - Page 18

STATINS and MUSCLE PAIN Karen Kennedy Introduction Statins are prescribed in New Zealand as first-line medicines to lower lipids for the primary and secondary prevention of cardiovascular disease (CVD) (Scott 2017). They inhibit 3- hydroxy-3-methylglutaryl- coenzyme A (HMGCoA) reductase preventing the formation of cholesterol. While statins are generally well- tolerated, adverse effects and in particular, muscle-related symptoms, contribute to non- adherence and a lack of long- term persistence in taking statins. Evidence has shown 5%-20% of patients stop taking statins due to unacceptable adverse effects. (Sweidan 2017). This increases CVD risk with the associated increased risk of morbidity and mortality (Jacobson 2017; Pirillo 2015). Myalgia Karen is a clinical advisory pharmacist and community pharmacy owner, who also works in general practice and locums for hospital pharmacy. She leads education for the pharmacists in her region. She is a member of the South Island (SI) Health of Older Persons Service Level Alliance and SI Palliative Care Workstream and sits on the Clinical Board for SCDHB. She has a Diploma in Pharmacy and a Post Graduate Diploma in Clinical Pharmacy. Mild to moderate myalgia (muscle pain and weakness with little or no creatine kinase (CK) elevation) is the most common statin- associated muscle symptom experienced by 7 to 29% of people as observed in practice (Jacobson 2017; Stroes 2015). This is higher than the incidence of SAMS observed in clinical trials, likely due to the selection process used for participants with exclusion of people with increased risk for muscle symptoms including older people, people with comorbidities, people with a history of muscle symptoms and people who showed muscle symptoms during a run-in period of the trial (Jacobson 2017; Pirillo 2015; Stroes 2015). The higher incidence of SAMS observed in practice compared to clinical trials may also be due to the muscle side effects being a result of another factor and not caused by statin use. The March 2018 L.O.G.I.C true incidence of myopathy due to statins is difficult to determine as the background rate of muscle symptoms in the general population is high (Jacobson 2017). A nocebo effect is also thought to play a part with patients more likely to report muscle-symptoms due to media reports of statin side effects or if they have been informed by their doctor or another person that muscle symptoms are a possibility (Jacobson 2017; Stroes 2015). A withdrawal of the offending statin and a re-challenge can help to determine if the statin is the precipitating factor (Stroes 2015). Myalgia may present as muscle pain, stiffness or cramping, tenderness, heaviness, aching or weakness. Weakness can occur without pain and people may experience this as finding it 16