An assessment of statin safety by muscle experts

Genetic and immunologic susceptibility to statin-related myopathy

Statin-related myopathy (SRM) undermines drug adherence that is critical for achieving the benefits of lipid-lowering therapy. While the exact mechanism of SRM remains largely unknown, recent evidence supports specific genetic and immunologic influence on the development of intolerance. Genes of interest include those involved in the pharmacokinetics of statin response (i.e. drug metabolism, uptake transporters, and efflux transporters), pharmacodynamics (i.e. drug toxicity and immune-mediated myopathy), and gene expression. We examine the influence of genetic and immunologic variation on the pharmacokinetics, pharmacodynamics, and gene expression of SRM.

Statin intolerance - an attempt at a unified definition. Position paper from an International Lipid Expert Panel

Statins are one of the most commonly prescribed drugs in clinical practice. They are usually well tolerated and effectively prevent cardiovascular events. Most adverse effects associated with statin therapy are muscle-related. The recent statement of the European Atherosclerosis Society (EAS) has focused on statin associated muscle symptoms (SAMS), and avoided the use of the term 'statin intolerance'. Although muscle syndromes are the most common adverse effects observed after statin therapy, excluding other side effects might underestimate the number of patients with statin intolerance, which might be observed in 10-15% of patients. In clinical practice, statin intolerance limits effective treatment of patients at risk of, or with, cardiovascular disease. Knowledge of the most common adverse effects of statin therapy that might cause statin intolerance and the clear definition of this phenomenon is crucial to effectively treat patients with lipid disorders. Therefore, the aim of this position paper was to suggest a unified definition of statin intolerance, and to complement the recent EAS statement on SAMS, where the pathophysiology, diagnosis and the management were comprehensively presented.

Risk identification and possible countermeasures for muscle adverse effects during statin therapy

The use of statins for cardiovascular disease prevention is clearly supported by clinical evidence. However, in January 2014 the U.S. Food and Drug Administration released an advice on statin risk reporting that "statin benefit is indisputable, but they need to be taken with care and knowledge of their side effects". Among them the by far most common complication is myopathy, ranging from common but clinically benign myalgia to rare but life-threatening rhabdomyolysis. This class side effect appears to be dose dependent, with more lipophilic statin (i.e., simvastatin) carrying a higher overall risk. Hence, to minimize statin-associated myopathy, clinicians should take into consideration a series of factors that potentially increase this risk (i.e., drug-drug interactions, female gender, advanced age, diabetes mellitus, hypothyroidism and vitamin D deficiency). Whenever it is appropriate to stop statin treatment, the recommendations are to stay off statin until resolution of symptoms or normalization of creatine kinase values. Afterwards, clinicians have several options to treat dyslipidemia, including the use of a lower dose of the same statin, intermittent non-daily dosing of statin, initiation of a different statin, alone or in combination with nonstatin lipid-lowering agents, and substitution with red yeast rice.

Statin adverse effects: patients' experiences and laboratory monitoring of muscle and liver injuries

BACKGROUND

Although statins have great benefit on the prevention of cardiovascular diseases with limited adverse effects (AEs), little is known about patients' contribution of AE reports in clinical practice.

OBJECTIVES

To explore patients' experiences of statin AEs and related laboratory monitoring in clinical practice.

SETTING

Outpatient clinics of two University hospitals in northeast Thailand.

METHODS

Generic symptom checklist questionnaires for self-reporting AEs were distributed to patients prescribed simvastatin, atorvastatin, or rosuvastatin at outpatient clinics. Clinical information was obtained from medical records. Reported symptoms were assessed for causality considering previously known statin AEs, concomitant diseases and drugs.

MAIN OUTCOME MEASURE

Potential statin AEs reported by patients and monitoring of laboratory parameters related to musculoskeletal and liver disorders.

RESULTS

Of the total 718 valid responses, 76.0 % of patients reported at least one symptom, most of which (69.0 %) were probable/possible statin AEs. Musculoskeletal and liver-related symptoms were reported by 283 (39.4 %) and 134 patients (18.7 %), respectively. Probable/possible AEs were categorized in 56.7 % of their musculoskeletal and gastrointestinal symptoms. Majority of patients had at least one laboratory test on initiation of (64.8 %) and during statin treatment (61.8 %). Patients taking atorvastatin or rosuvastatin, and patients with history of chronic renal diseases were more likely to have creatine kinase (CK) monitored on initiation of and during statin treatment. Additionally, taking drugs which could potentially increase muscle injury (OR 1.929, P < 0.01) and self-reporting of musculoskeletal symptoms (OR 1.805, P < 0.01) were associated with CK monitoring during statin treatment. Reporters of musculoskeletal symptoms also had significantly higher mean CK level than those not reporting any musculoskeletal symptoms (207.35 ± 155.40 vs. 143.95 ± 83.07 U/L, respectively; P = 0.037). Patient reporting of liver AEs was not related to alanine aminotransferase (ALT) level and monitoring, however, prior history of liver disorders was significantly associated with monitoring of ALT on initiation of and during statin treatment (OR 5.745 and OR 23.063, respectively; P < 0.01).

CONCLUSION

Many patients experienced at least one possible adverse effects on a statin. The findings suggest that laboratory monitoring is relatively selective in relation to risks and patient-reported adverse symptoms.

Bioengineered human myobundles mimic clinical responses of skeletal muscle to drugs

Existing in vitro models of human skeletal muscle cannot recapitulate the organization and function of native muscle, limiting their use in physiological and pharmacological studies. Here, we demonstrate engineering of electrically and chemically responsive, contractile human muscle tissues (‘myobundles’) using primary myogenic cells. These biomimetic constructs exhibit aligned architecture, multinucleated and striated myofibers, and a Pax7⁺ cell pool. They contract spontaneously and respond to electrical stimuli with twitch and tetanic contractions. Positive correlation between contractile force and GCaMP6-reported calcium responses enables non-invasive tracking of myobundle function and drug response. During culture, myobundles maintain functional acetylcholine receptors and structurally and functionally mature, evidenced by increased myofiber diameter and improved calcium handling and contractile strength. In response to diversely acting drugs, myobundles undergo dose-dependent hypertrophy or toxic myopathy similar to clinical outcomes. Human myobundles provide an enabling platform for predictive drug and toxicology screening and development of novel therapeutics for muscle-related disorders.

DOI:http://dx.doi.org/10.7554/eLife.04885.001

Scientists have developed realistic models of the human liver, lung, and heart that allow them to observe living tissue in the laboratory. These models have helped us to better understand how these organs work and what goes wrong in diseases that affect these organs. The models can also be used to test how new drugs may affect a particular organ without the risk of exposing patients to the drug.

Efforts to develop a realistic laboratory model of human muscle tissues that can contract like real muscles have not been as successful to date. This shortcoming has potentially hindered the development of drugs to treat numerous disorders that affect muscles and movement in humans—such as muscular dystrophies, which are diseases in which people progressively lose muscle strength.

Some important drugs, like cholesterol-lowering statins, have detrimental effects on muscle tissue; one statin was so harmful to muscles that it had to be withdrawn from the market. As such, it would be useful to have experimental models that would allow scientists to test whether potential drugs damage or treat muscle tissue.

Madden et al. have now bioengineered a three-dimensional laboratory model of living muscle tissue made of cells taken from biopsies of several different human patients. These tissues were grown into bundles of muscle fibers on special polymer frames in the laboratory. The bioengineered muscle bundles respond to electrical and chemical signals and contract just like normal muscle. They also exhibit the same structure and signaling as healthy muscle tissue in humans.

Madden et al. exposed the muscle tissue bundles to three drugs known to affect muscles to determine if the model could be used to test whether drugs have harmful effects. This revealed that the bundles had weaker contractions in response to statins and the malaria drug chloroquine, just like normal muscles do—and that this effect worsened if more of each drug was used. Madden et al. also found that a drug that strengthens muscle contractions at low doses and damages muscle at high doses in humans has similar effects in the model.

As well as this model being used to screen for harmful effects of drugs before clinical trials, the technique used to create the model could be used to grow muscle tissue from patients with muscle diseases. This would help researchers and doctors to better understand the patient's condition and potentially develop more efficient therapies. Also, the technique could be eventually developed to grow healthy muscle tissue to implant in patients who have been injured.

DOI:http://dx.doi.org/10.7554/eLife.04885.002

Statin use and decline in gait speed in community-dwelling older adults

OBJECTIVES

To examine the association between statin use and objectively assessed decline in gait speed in community-dwelling older adults.

DESIGN

Longitudinal cohort study.

SETTING

Health, Aging and Body Composition (Health ABC) Study.

PARTICIPANTS

Two thousand five participants aged 70-79 at baseline with medication and gait speed data at 1998-99, 1999-2000, 2001-02, and 2002-03.

MEASUREMENTS

The independent variables were any statin use and their standardized daily doses (low, moderate, high) and lipophilicity. The primary outcome measure was decline in gait speed of 0.1 m/s or more in the following year of statin use. Multivariable generalized estimating equations were used, adjusting for demographic characteristics, health-related behaviors, health status, and access to health care.

RESULTS

Statin use increased from 16.2% in 1998-99 to 25.6% in 2002-03. The overall proportions of those with decline in gait speed of 0.1 m/s or more increased from 22.2% in 1998 to 23.9% in 2003. Statin use was not associated with decline in gait speed of 0.1 m/s or more (adjusted odds ratio (AOR) = 0.90, 95% confidence interval (CI) = 0.77-1.06). Similar nonsignificant trends were also seen with the use of hydrophilic or lipophilic statins. Users of low-dose statins were found to have a 22% lower risk of decline in gait speed than nonusers (AOR = 0.78, 95% CI = 0.61-0.99), which was mainly driven by the results from 1999-2000 follow-up.

CONCLUSION

These results suggest that statin use did not increase decline in gait speed in community-dwelling older adults.

An assessment by the Statin Muscle Safety Task Force: 2014 update

The National Lipid Association's Muscle Safety Expert Panel was charged with the duty of examining the definitions for statin-associated muscle adverse events, development of a clinical index to assess myalgia, and the use of diagnostic neuromuscular studies to investigate muscle adverse events. We provide guidance as to when a patient should be considered for referral to neuromuscular specialists and indications for the performance of a skeletal muscle biopsy. Based on this review of evidence, we developed an algorithm for the evaluation and treatment of patients who may be intolerant to statins as the result of adverse muscle events. The panel was composed of clinical cardiologists, clinical lipidologists, an exercise physiologist, and a neuromuscular specialist.

A Neuromuscular Approach to Statin-Related Myotoxicity

Approximately 95% of statin-treated patients tolerate this form of cholesterol management without any adverse effects. However, given their efficacy in reducing low density lipoproteins and cardiovascular events large numbers of patients are selected for statin therapy. Therefore muscle complications are, in fact, quite common. Limited understanding of the underlying pathophysiology has hampered physicians' ability to identify patients at risk for developing statin myotoxicity. A growing number of published case reports/series have implicated statins in the exacerbation of both acquired and genetic myopathies. A clinical management algorithm is presented which outlines a variety of co-morbidities which can potentiate the adverse effects of statins on muscle. In addition, a rational approach to the selection of those patients most likely to benefit from skeletal muscle biopsy is discussed. Ongoing work will define the extent to which statin-intolerant patients represent carriers of recessive metabolic myopathies or pre-symptomatic acquired myopathies. The expanding importance of pharmacogenomics will undoubtedly be realized in the field of statin myopathy research within the next few years. Such critical information is needed to establish more definitive management and diagnostic strategies.

Mechanisms and assessment of statin-related muscular adverse effects

Statin-associated muscular adverse effects cover a wide range of symptoms, including asymptomatic increase of creatine kinase serum activity and life-threatening rhabdomyolysis. Different underlying pathomechanisms have been proposed. However, a unifying concept of the pathogenesis of statin-related muscular adverse effects has not emerged so far. In this review, we attempt to categorize these mechanisms along three levels. Firstly, among pharmacokinetic factors, it has been shown for some statins that inhibition of cytochrome P450-mediated hepatic biotransformation and hepatic uptake by transporter proteins contribute to an increase of systemic statin concentrations. Secondly, at the myocyte membrane level, cell membrane uptake transporters affect intracellular statin concentrations. Thirdly, at the intracellular level, inhibition of the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase results in decreased intracellular concentrations of downstream metabolites (e.g. selenoproteins, ubiquinone, cholesterol) and alteration of gene expression (e.g. ryanodine receptor 3, glycine amidinotransferase). We also review current recommendations for prescribers.

Safety of statins: an update

Statins are widely used and have been proven to be effective in the prevention of atherosclerotic vascular disease events, primarily by reducing plasma low-density lipoprotein cholesterol concentrations. Although statins are generally well tolerated and present an excellent safety profile, adverse effects from muscle toxicity and liver enzyme abnormalities may occur in some patients. Myopathy and rhabdomyolysis are rare with statin monotherapy at the approved dose ranges, but the risk increases with use of higher doses, interacting drugs and genetic predisposition. Asymptomatic increases in liver transaminases with statin treatment do not seem to be associated with an increased risk of liver disease. Therefore, statin treatment can be safely used in patients with mild to moderately abnormal liver tests that are potentially attributable to nonalcoholic fatty liver disease and can improve liver tests and reduce cardiovascular morbidity in this group of patients. The risks of other unfavorable effects such as the slightly increased risk of new-onset diabetes and potentially increased risk of haemorrhagic stroke are much smaller than the cardiovascular benefits with the use of statins.

Translational insight into statin-induced muscle toxicity: from cell culture to clinical studies

Statins are lipid-lowering drugs used widely to prevent and treat cardiovascular and coronary heart diseases. These drugs are among the most commonly prescribed medicines intended for long-term use. In general, statins are well tolerated. However, muscular adverse effects appear to be the most common obstacle that limits their use, resulting in poor patient compliance or even drug discontinuation. In addition, rare but potentially fatal cases of rhabdomyolysis have been reported with the use of these drugs, especially in the presence of certain risk factors. Previous reports have investigated statin-induced myotoxicity in vivo and in vitro using a number of cell lines, muscle tissues, and laboratory animals, in addition to randomized clinical trials, observational studies, and case reports. None of them have compared directly results from laboratory investigations with clinical observations of statin-related muscular adverse effects. To the best of our knowledge this is the first review article that combines laboratory investigation with clinical aspects of statin-induced myotoxicity. By reviewing published literature of in vivo, in vitro, and clinically relevant studies of statin myotoxicity, we aim to translate this important drug-related problem to establish a clear picture of proposed mechanisms that explain the risk factors and describe the diagnostic approaches currently used for evaluating the degree of muscle damage induced by these agents. This review provides baseline novel translational insight that can be used to enhance the safety profile, to minimize the chance of progression of these adverse effects to more severe and potentially fatal rhabdomyolysis, and to improve the overall patient compliance and adherence to long-term statin therapy.

Clinical decisions in patients with diabetes and other cardiovascular risk factors. A statement of the Spanish Society of Internal Medicine

Although the mortality associated to cardiovascular diseases (CVD) has been reduced in the last decades, CVD remains the main cause of mortality in Spain and they are associated with an important morbidity and a huge economic burden. The increasing prevalence of obesity and diabetes could be slowing down the mortality reduction in Spain. Clinicians have often difficulty making clinical decisions due to the multiple clinical guidelines available. Moreover, in the current context of economic crisis it is critical to promote an efficient use of diagnostic and therapeutic proceedings to ensure the viability of public health care systems. The Spanish Society of Internal Medicine (SEMI) has coordinated a consensus document to answer questions of daily practice with the aim of facilitating physicians' decision-making in the management of diabetes and cardiovascular risk factors from a cost-efficiency point of view.

Experimental nonalcoholic steatohepatitis increases exposure to simvastatin hydroxy acid by decreasing hepatic organic anion transporting polypeptide expression

Simvastatin (SIM)-induced myopathy is a dose-dependent adverse drug reaction (ADR) that has been reported to occur in 18.2% of patients receiving a 40- to 80-mg dose. The pharmacokinetics of SIM hydroxy acid (SIMA), the bioactive form of SIM, and the occurrence of SIM-induced myopathy are linked to the function of the organic anion transporting polypeptide (Oatp) hepatic uptake transporters. Genetic polymorphisms in SLCO1B1, the gene for human hepatic OATP1B1, cause decreased elimination of SIMA and increased risk of developing myopathy. Nonalcoholic steatohepatitis (NASH) is the most severe form of nonalcoholic fatty liver disease, and is known to alter drug transporter expression and drug disposition. The purpose of this study was to assess the metabolism and disposition of SIM in a diet-induced rodent model of NASH. Rats were fed a methionine- and choline-deficient diet for 8 weeks to induce NASH and SIM was administered intravenously. Diet-induced NASH caused increased plasma retention and decreased biliary excretion of SIMA due to decreased protein expression of multiple hepatic Oatps. SIM exhibited increased volume of distribution in NASH as evidenced by increased muscle, decreased plasma, and no change in biliary concentrations. Although Cyp3a and Cyp2c11 proteins were decreased in NASH, no alterations in SIM metabolism were observed. These data, in conjunction with our previous data showing that human NASH causes a coordinated downregulation of hepatic uptake transporters, suggest that NASH-mediated transporter regulation may play a role in altered SIMA disposition and the occurrence of myopathy.

A Clinical Review of Statin-Associated Myopathy

Objective: To review the epidemiology, clinical features, proposed mechanisms, risk factors, and management of statin-associated myopathy. Data Sources: Literature searches were conducted in PubMed (1948 to April 2013), TOXLINE, International Pharmaceutical Abstracts (1970 to April 2013), and Google Scholar using the terms statin, hydroxymethylglutaryl-coenzyme A reductase inhibitors, myopathy, myalgia, safety, and rhabdomyolysis. Results were limited to English publications. Study Selection and Data Extraction: All relevant original studies, guidelines, meta-analyses, and reviews of statin-associated myopathy and safety of statins were assessed for inclusion. References from selected articles were reviewed to identify additional citations. Data Synthesis: The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors remain one of the most effective medications for reducing low-density-lipoprotein cholesterol. Statins are well tolerated by most patients; however, it is estimated that 10% to 15% of patients develop statin-related muscle adverse effects known as statin-associated myopathy. Although clinicians may be aware of statin-associated myopathy, they may not be aware of its clinical presentation. Providers should assess individual patient risk factors before choosing the appropriate statin. A variety of skeletal muscle aches that may not present as a danger to the patient, may affect patient adherence and quality of life. There are several steps that providers can take to properly treat and manage patients with myalgia complaints. Conclusions: Statin-associated myopathy is a clinical problem that contributes to statin therapy discontinuation. Patients who are statin intolerant may be treated with alternative treatment options such as low-dose statins, switching statins, using alternative dosing strategies in statins with longer half-lives, non-statin lipid-lowering agents, and complementary therapies.

Statin myotoxicity: a review of genetic susceptibility factors

The 3-hydroxy-3-methylglutaryl coenzyme A (HMGCoA) reductase inhibitors (statins) are among the most common medications prescribed worldwide, but their efficacy and toxicity vary between individuals. One of the major factors contributing to intolerance and non-compliance are the muscle side-effects, which range from mild myalgia through to severe life-threatening rhabdomyolysis. One way to address this is pharmacogenomic screening, which aims to individualize therapy to maximize efficacy whilst avoiding toxicity. Genes encoding proteins involved in the metabolism of statins as well as genes known to cause inherited muscle disorders have been investigated. To-date only polymorphisms in the SLCO1B1 gene, which encodes the protein responsible for hepatic uptake of statins, and the COQ2 gene, important in the synthesis of coenzyme Q10, have been validated as being strongly associated with statin-induced myopathy. The aim of this review is to summarize studies investigating genetic factors predisposing to statin myopathy and myalgia, as the first step towards pharmacogenomic screening to identify at risk individuals.

Clinical and pharmacogenetic predictors of circulating atorvastatin and rosuvastatin concentrations in routine clinical care

BACKGROUND

A barrier to statin therapy is myopathy associated with elevated systemic drug exposure. Our objective was to examine the association between clinical and pharmacogenetic variables and statin concentrations in patients.

METHODS AND RESULTS

In total, 299 patients taking atorvastatin or rosuvastatin were prospectively recruited at an outpatient referral center. The contribution of clinical variables and transporter gene polymorphisms to statin concentration was assessed using multiple linear regression. We observed 45-fold variation in statin concentration among patients taking the same dose. After adjustment for sex, age, body mass index, ethnicity, dose, and time from last dose, SLCO1B1 c.521T>C (P<0.001) and ABCG2 c.421C>A (P<0.01) were important to rosuvastatin concentration (adjusted R(2)=0.56 for the final model). Atorvastatin concentration was associated with SLCO1B1 c.388A>G (P<0.01) and c.521T>C (P<0.05) and 4β-hydroxycholesterol, a CYP3A activity marker (adjusted R(2)=0.47). A second cohort of 579 patients from primary and specialty care databases were retrospectively genotyped. In this cohort, genotypes associated with statin concentration were not differently distributed among dosing groups, implying providers had not yet optimized each patient's risk-benefit ratio. Nearly 50% of patients in routine practice taking the highest doses were predicted to have statin concentrations greater than the 90th percentile.

CONCLUSIONS

Interindividual variability in statin exposure in patients is associated with uptake and efflux transporter polymorphisms. An algorithm incorporating genomic and clinical variables to avoid high atorvastatin and rosuvastatin levels is described; further study will determine whether this approach reduces incidence of statin myopathy.

Statin-associated polymyositis following omeprazole treatment

Statins are an extensively used class of drugs, and myopathy is an uncommon, but well-described side effect of statin therapy. Inflammatory myopathies, including polymyositis, dermatomyositis, and necrotizing autoimmune myopathy, are even more rare, but debilitating, side effects of statin therapy that are characterized by the persistence of symptoms even after discontinuation of the drug. It is important to differentiate statin-associated inflammatory myopathies from other self-limited myopathies, as the disease often requires multiple immunosuppressive therapies. Drug interactions increase the risk of statin-associated toxic myopathy, but no risk factors for statin-associated inflammatory myopathies have been established. Here we describe the case of a man, age 59 years, who had been treated with a combination of atorvastatin and gemfibrozil for approximately 5 years and developed polymyositis after treatment with omeprazole for 7 months. Symptoms did not resolve after discontinuation of the atorvastatin, gemfibrozil, and omeprazole. The patient was treated with prednisone and methotrexate followed by intravenous immunoglobulin, which resulted in normalization of creatinine kinase levels and resolution of symptoms after 14 weeks. It is unclear if polymyositis was triggered by interaction of the statin with omeprazole and/or gemfibrozil, or if it developed secondary to long-term use of atorvastatin only.

The controversy of a wider statin utilization: why?

INTRODUCTION

Several medical journals published viewpoints and counter-viewpoints supporting or opposing a wider utilization of statins for primary prevention. The objective of this article is not to weigh in the benefits versus risks of statin use, but to discuss various aspects of this controversy.

AREAS COVERED

This review discusses the challenges in examining the pleotropic effects/adverse events of statins. It also discusses the pitfalls in assessment of adverse events in randomized controlled trials and observational studies.

EXPERT OPINION

The challenges in solving this controversy include that the pleotropic effect of statins results in an extremely wide spectrum of reported benefits or adverse events, the reported harms/benefits are contradictory, there is basic research ground supporting both sides of the controversy, it is difficult to separate if adverse events are due to statins or due to lower cholesterol, and that there is a lack of standardized definition of statin-associated adverse events and their methods of ascertainment. Both randomized controlled trials and observational studies have pitfalls and caveats in assessment of adverse events. Understanding the points of debate is of paramount significance to enable clinicians to individualize patient care.

Ranolazine-induced myopathy in a patient on chronic statin therapy

We present a case demonstrating clinical, electrophysiological, serological, and radiological evidence of a myopathy induced by ranolazine, in a patient otherwise asymptomatic on chronic statin therapy. The patient developed proximal weakness, serum creatine kinase levels of 1875 U/L, electromyography with muscle membrane instability and small short-duration motor unit potentials, and magnetic resonance imaging evidence of muscle edema. The manifestations began within one week of initiation of ranolazine and improved within days after discontinuation. Ranolazine is a weak inhibitor of CYP3A4 known to increase the serum level of simvastatin and its active metabolite 2-fold. We postulate that the addition of ranolazine to a medical regimen that included atorvastatin induced a myoncecrotic myopathy.

Case report of exercise and statin-fibrate combination therapy-caused myopathy in a patient with metabolic syndrome: contradictions between the two main therapeutic pathways

Background

Lifestyle modifications including exercise are beneficial and fundamentally part of the therapy of metabolic syndrome, although in most of the cases medical interventions are also required to reach the target values in the laboratory parameters. Statin and fibrate combination therapy is considered to be safe and effective in dyslipidaemia and metabolic syndrome. However, increased physical activity can enhance the statin and fibrate-associated myopathy. Myositis and the rare but life-threatening rhabdomyolysis are causing a conflict between exercise and statin-fibrate therapy, which is yet to be resolved.

Case presentation

We present a case of a 43-year-old Caucasian man with metabolic syndrome who had the side-effect of exercise and drug-associated myositis. The patient had only transient moderate complaints and rhabdomyolysis could be avoided with the one-month creatine kinase control, a test which is not recommended routinely by the new guidelines.

Conclusions

We would like to turn the spotlight on the possible complications of statin-fibrate therapy and exercise, when strict follow-up is recommended. In this condition high number of patients can be affected and the responsibility of general practitioners is accentuated.

Muscular effects of statins in the elderly female: a review

Statins have demonstrated substantial benefits in supporting cardiovascular health. Older individuals are more likely to experience the well-known muscle-related side effects of statins compared with younger individuals. Elderly females may be especially vulnerable to statin-related muscle disorder. This review will collate and discuss statin-related muscular effects, examine their molecular and genetic basis, and how these apply specifically to elderly women. Developing strategies to reduce the incidence of statin-induced myopathy in older adult women could contribute to a significant reduction in the overall incidence of statin-induced muscle disorder in this vulnerable group of patients. Reducing statin-related muscle disorder would likely improve overall patient compliance, thereby leading to an increase in improved short- and long-term outcomes associated with appropriate use of statins.

Individualized risk for statin-induced myopathy: current knowledge, emerging challenges and potential solutions

Skeletal muscle toxicity is the primary adverse effect of statins. In this review, we summarize current knowledge regarding the genetic and nongenetic determinants of risk for statin induced myopathy. Many genetic factors were initially identified through candidate gene association studies limited to pharmacokinetic (PK) targets. Through genome-wide association studies, it has become clear that SLCO1B1 is among the strongest PK predictors of myopathy risk. Genome-wide association studies have also expanded our understanding of pharmacodynamic candidate genes, including RYR2. It is anticipated that deep resequencing efforts will define new loci with rare variants that also contribute, and sophisticated computational approaches will be needed to characterize gene-gene and gene-environment interactions. Beyond environment, race is a critical covariate, and its influence is only partly explained by geographic differences in the frequency of known pharmacodynamic and PK variants. As such, admixture analyses will be essential for a full understanding of statin-induced myopathy.

Emphasizing statin safety in the hospitalized patient: a review

This review examines the safe use of statin therapy in the hospitalized patient. Available data support initiation of statin therapy during hospitalization in patients with acute coronary syndromes or established cardiovascular disease and in high-risk patients with diabetes mellitus and chronic kidney disease (except for those on maintenance hemodialysis). Because of the increased risk of cardiovascular disease, statins are given to solid-organ transplant survivors and those treated with protease inhibitors for human immunodeficiency virus. However, in the multidrug, acute illness hospital environment, safety considerations become paramount. We review the essentials of statin metabolism and drug-drug interactions to provide the hospital physician with information to minimize potentially serious adverse statin effects.

Statin drug interactions and related adverse reactions

INTRODUCTION

Statin monotherapy is generally well tolerated, with a low frequency of adverse events. The most important adverse effects associated with statins are myopathy and an asymptomatic increase in hepatic transaminases, both of which occur infrequently. Because statins are prescribed on a long-term basis, their possible interactions with other drugs deserve particular attention, as many patients will typically receive pharmacological therapy for concomitant conditions during the course of statin treatment.

AREAS COVERED

This review summarizes the pharmacokinetic properties of statins and emphasizes their clinically relevant drug interactions and related adverse reactions.

EXPERT OPINION

Avoiding drug-drug interactions and consequent adverse drug reactions is essential in order to optimize compliance, and thus improve the treatment of patients at high cardiovascular risk. The different pharmacokinetic profiles among statins should be carefully considered, in order to understand the possible spectrum of drug interactions. The growing trend toward earlier statin treatment for the prevention of cardiovascular disease means that physicians must anticipate future polypharmacy when their patients require additional medications for comorbid conditions.

Statin induced myotoxicity

Statins are an effective treatment for the prevention of cardiovascular diseases and used extensively worldwide. However, myotoxicity induced by statins is a common adverse event and a major barrier to maximising cardiovascular risk reduction. The clinical spectrum of statin induced myotoxicity includes asymptomatic rise in creatine kinase concentration, myalgia, myositis and rhabdomyolysis. In certain cases, the cessation of statin therapy does not result in the resolution of muscular symptoms or the normalization of creatine kinase, raising the possibility of necrotizing autoimmune myopathy. There is increasing understanding and recognition of the pathophysiology and risk factors of statin induced myotoxicity. Careful history and physical examination in conjunction with selected investigations such as creatine kinase measurement, electromyography and muscle biopsy in appropriate clinical scenario help diagnose the condition. The management of statin induced myotoxicity involves statin cessation, the use of alternative lipid lowering agents or treatment regimes, and in the case of necrotizing autoimmune myopathy, immunosuppression.

Daily and intermittent rosuvastatin 5 mg therapy in statin intolerant patients: an observational study

OBJECTIVE

To examine the efficacy and tolerability of rosuvastatin 5 mg at daily and non-daily dosing regimens.

RESEARCH DESIGN AND METHODS

A retrospective survey was conducted at nine primary, secondary and tertiary healthcare centres in the United Kingdom.

MAIN OUTCOME MEASURES

Changes in lipid fractions from baseline values after more than 3 months' treatment.

RESULTS

A total of 325 patients were identified. These patients were aged 63 ± 10 years, 50% male and prescription was mostly for primary prevention of cardiovascular disease (CVD) (59%). Co-morbidities included: established CVD present in 41%, type 2 diabetes mellitus (15%), hypertension (74%) and smoking (9%). Adverse effects had been documented to simvastatin (75%) or atorvastatin (63%). A total of 289 patients (89%) tolerated rosuvastatin well and were still adherent after a median follow-up of 14.9 (3-79) months. The remainder (n = 36; 11%) discontinued the medication after median 5 months' treatment due to adverse effects. Efficacy was assessed in 224 patients who had adequate data. Baseline lipids were total cholesterol (TC) 7.41 ± 1.50 mmol/L, triglycerides (TG) 2.26 (range 0.36-18.4) mmol/L; high density lipoprotein cholesterol (HDL-C) 1.43 ± 0.47 mmol/L and low density lipoprotein cholesterol (LDL-C) 4.76 ± 1.38 mmol/L. Daily rosuvastatin (n = 134) reduced mean TC by 31%, TG 15% and LDL-C 43% (p < 0.001). Rosuvastatin 5 mg 2-3 times weekly (n = 79) reduced TC 26%, TG 16% and LDL-C 32% (p < 0.001). Weekly rosuvastatin (n = 11) reduced TC 17%, LDL-C by 23% (p < 0.001) but had no effect on TGs. Targets were attained in 17% of CHD-risk equivalent patients and 41% of primary prevention patients by National Cholesterol Education Program criteria and 27% and 68% using UK targets. No myositis or rhabdomyolysis was observed and alanine aminotransferase (ALT) and creatine kinase (CK) were similar to baseline.

CONCLUSIONS

In this retrospective observational multicentre study, rosuvastatin 5 mg was found to be safe and biochemically effective either as daily or intermittent therapy in patients intolerant to other conventional statin regimens.

No adverse effects of statins on muscle function and health-related parameters in the elderly: an exercise study

The aim of the present study was to investigate the effects of a repeated bout of eccentric exercise on health-related parameters and muscle performance on subjects undergoing atorvastatin therapy. Twenty-eight elderly men participated in the investigation and were assigned either in a control (n = 14) or in a statin therapy group (n = 14). All participants performed two isokinetic eccentric exercise bouts separated by 3 weeks. Muscle damage indices, resting energy expenditure, substrate metabolism, lipid and lipoprotein profile, as well as insulin sensitivity, were evaluated before and after eccentric. No differences in muscle function were observed between the two groups either at rest or after exercise. Eccentric exercise increased resting energy expenditure, increased fat oxidation, improved lipid profile, and increased insulin resistance 2 days after both eccentric exercise bouts. However, these changes appeared to lesser extent after the second bout. No differences were observed in the responses in the health-related parameters in the control and in the statin therapy group. Eccentric exercise affected similarly the control and the atorvastatin-treated individuals. The present results indicate that atorvastatin-treated elderly individuals may participate in various physical activities, even high-intensity muscle-damaging activities, without negative impact on muscle function and adaptation.

Diagnosis, prevention, and management of statin adverse effects and intolerance: proceedings of a Canadian Working Group Consensus Conference

While the proportion of patients with significant statin-associated adverse effects or intolerance is very low, the increasing use and broadening indications have led to a significant absolute number of such patients commonly referred to tertiary care facilities and specialists. This report provides a comprehensive overview of the evidence pertaining to a broad variety of statin-associated adverse effects followed by a consensus approach for the prevention, assessment, diagnosis, and management. The overview is intended both to provide clarification of the untoward effects of statins and to impart confidence in managing the most common issues in a fashion that avoids excessive ancillary testing and/or subspecialty referral except when truly necessary. The ultimate goal is to ensure that patients who warrant cardiovascular risk reduction can be treated optimally, safely, and confidently with statin medications or alternatives when warranted.

Long-term effects of nutraceuticals (berberine, red yeast rice, policosanol) in elderly hypercholesterolemic patients

INTRODUCTION

Statins are at the forefront of strategies to manage dyslipidemia, although they are not always well tolerated. At 6-7 months after the drug was supplied, discontinuation rates averaged 30%. Alternate agents to statins have been studied. Some nutraceuticals demonstrated an efficacy in reducing cholesterol concentrations. However, there are no data regarding the use of nutraceuticals in elderly dyslipidemic patients. The purpose of this study was to examine the efficacy, safety, and tolerability of a nutraceutical-based protocol in elderly hypercholesterolemic patients previously intolerant to statins.

METHODS

This study was performed as a randomized, prospective, parallel group, single-blind study. Patients were included in the study if they had high total cholesterolemia, high low-density lipoprotein cholesterol (LDL-C), >75 years of age, statin-intolerant, and were refusing other pharmaceutical treatments for hypercholesterolemia. At the baseline visit, eligible patients were randomized to either nutraceutical-combined pill (containing berberine 500 mg, policosanol 10 mg, red yeast rice 200 mg, folic acid 0.2 mg, coenzyme Q10 2.0 mg, and astaxanthin 0.5 mg) or placebo, and the first dose was dispensed. The efficacy, safety, and tolerability of the proposed treatment were fully assessed after 3, 6, and 12 months of treatment.

RESULTS

Out of 106 consecutive patients screened, 80 eligible patients were randomized to receive either nutraceutical-combined pill (40 patients) or placebo (40 patients). No patients were lost and no deaths occurred during the follow-up. There was a statistically significant reduction in total cholesterolemia (-20%), LDL-C (-31%), and insulin resistance (-10%) with nutraceutical treatment. No significant changes were detected for plasma high-density lipoprotein cholesterol (HDL-C). Furthermore, no statistical differences were found between baseline and end-study safety parameters. Medication compliance and tolerability were high.

CONCLUSION

In this study the authors have demonstrated that combined nutraceuticals significantly reduce cholesterolemia and achieved acceptable plasma LDL-C levels in elderly hypercholesterolemic patients who were previously statin-intolerant. Combined nutraceuticals is also safe and well tolerated in these patients.

Fluvastatin-induced alterations of skeletal muscle function in hypercholesterolaemic rats

Although statins, the most widely used drugs in the treatment of hyperlipidaemia, are generally accepted as efficient and safe drugs their side-effects on skeletal muscle have been reported with increasing frequency. The lack of an animal model in which these side effects would consistently be observed is one of the important drawbacks in studying statin associated myopathy. To overcome this and enable the studying of the effects of fluvastatin on skeletal muscles an animal model with high blood cholesterol levels was developed. In these animals cholesterol levels rose more than seven fold (from 1.5 ± 0.1 to 10.7 ± 2.0 mmol/l; n = 15 and 16) with a dramatic increase in low density lipoprotein/high density lipoprotein ratio (from 0.29 ± 0.02 to 1.56 ± 0.17). While the latter was reversed by statin treatment, an elevation in blood creatine kinase (CK) level indicated the presence of muscle wasting. Fibers from m. extensor digitorum longus (EDL) showed significant reduction in cross sectional area in the statin treated groups. Statin treatment also decreased the proliferation and fusion of skeletal myotubes in culture. In line with this, resting intracellular calcium concentration ([Ca(2+)](i)) was reduced in statin treated satellite cells and myotubes. On the other hand, in adult skeletal muscle fibers statin treatment increased resting [Ca(2+)](i) (116 ± 4 nM vs. 151 ± 5 nM; n = 33 and 34) and decreased both twitch and tetanic force both in EDL and m. soleus. In addition, in m. soleus the duration of twitch and tetanic force was shortened. These results clearly indicate that statin administration in these animals results in a myopathy characterized by decreased muscle force and elevated plasma CK level.

SLCO1B1 rs4149056 polymorphism associated with statin-induced myopathy is differently distributed according to ethnicity in the Brazilian general population: Amerindians as a high risk ethnic group

BACKGROUND

Recent studies reported the association between SLCO1B1 polymorphisms and the development of statin-induced myopathy. In the scenario of the Brazilian population, being one of the most heterogeneous in the world, the main aim here was to evaluate SLCO1B1 polymorphisms according to ethnic groups as an initial step for future pharmacogenetic studies.

METHODS

One hundred and eighty-two Amerindians plus 1,032 subjects from the general urban population were included. Genotypes for the SLCO1B1 rs4149056 (c.T521C, p.V174A, exon 5) and SLCO1B1 rs4363657 (g.T89595C, intron 11) polymorphisms were detected by polymerase chain reaction followed by high resolution melting analysis with the Rotor Gene 6000® instrument.

RESULTS

The frequencies of the SLCO1B1 rs4149056 and rs4363657 C variant allele were higher in Amerindians (28.3% and 26.1%) and were lower in African descent subjects (5.7% and 10.8%) compared with Mulatto (14.9% and 18.2%) and Caucasian descent (14.8% and 15.4%) ethnic groups (p<0.001 and p<0.001, respectively). Linkage disequilibrium analysis show that these variant alleles are in different linkage disequilibrium patterns depending on the ethnic origin.

CONCLUSION

Our findings indicate interethnic differences for the SLCO1B1 rs4149056 C risk allele frequency among Brazilians. These data will be useful in the development of effective programs for stratifying individuals regarding adherence, efficacy and choice of statin-type.

SLCO1B1 haplotypes are not associated with atorvastatin-induced myalgia in Brazilian patients with familial hypercholesterolemia

PURPOSE

Recent studies reported the association of SLCO1B1 haplotypes with the development of musculoskeletal side effects during simvastatin use. The aim was to evaluate the pharmacogenetic association of SLCO1B1 haplotypes with atorvastatin-induced myalgia in a sample of individuals on high-dose atorvastatin regimens.

METHODS

One hundred and forty-three patients with familial hypercholesterolemia were followed for at least 12 months while receiving atorvastatin. Genotypes for the rs2306283 (c.A388G) and rs4149056 (c.T521C) polymorphisms were detected by high-resolution melting analysis. These markers form four distinct haplotypes (*1A, *1B, *5 and *15).

RESULTS

During the follow-up period, 14 (9.8%) patients developed myalgia and 16 (11.2%) presented CK levels more than 3 times the upper limit of the normal range. No association of the SLCO1B1 rs2306283 and rs4149056 genotypes or haplotypes with the presence of myalgia or creatine kinase (CK) values was found. Presence of rs2306283 AG + GG genotypes was not associated with increased risks of myalgia or abnormal CK values (OR 2.08, 95% CI 0.62-7.00, p = 0.24 and OR 0.51, 95% CI 0.21-1.26, p = 0.15 respectively). The presence of rs4149056 TC + CC genotypes was also not associated with increased risk of myalgia or abnormal CK values (OR 2.24, 95% CI 0.47-10.72, p = 0.31 and OR 1.51, 95% CI 0.57-3.96, p = 0.41 respectively).

CONCLUSIONS

Our findings reaffirm that the SLCO1B1 genetic risk appears to be greater in those patients receiving simvastatin compared with those receiving atorvastatin. This suggests that the importance of SLCO1B1 haplotypes depends on the specific statin that has been used.

The epidemiology of sarcopenia in community living older adults: what role does lifestyle play?

BACKGROUND: Sarcopenia, the age-related decline in skeletal muscle mass and function, is a relatively poorly understood process which may play an important role in the incidence of physical disability and falls in older adults. Evidence demonstrates that both genetic and environmental factors contribute to increased susceptibility for sarcopenia development, yet some of these factors may represent unavoidable consequences of ageing. METHODS: A review of literature, generally from epidemiological research, was performed to examine the influence that potentially modifiable lifestyle factors (general physical activity, dietary nutrient intake and sun exposure), as well as chronic disease and medication use, may have on sarcopenia progression. RESULTS: The review demonstrated that while physical activity, nutrient intake and sun exposure often decline during ageing, each may have important but differing benefits for the prevention of muscle mass and functional declines in older adults. Conversely, age-related increases in the prevalence of chronic diseases and the subsequent prescription of pharmacotherapy may exacerbate sarcopenia progression. CONCLUSIONS: The prevalence of poor physical activity, diet and sun exposure, as well as chronic disease and medication use, within older adult populations may be modifiable through simple lifestyle and health care interventions. As such, these factors may represent the most effective targets for sarcopenia prevention during the ageing process.