HMG-CoA reductase inhibitors and myotoxicity

Drug-Induced Myopathies: A Comprehensive Review and Update

Drug-induced myopathies are a common cause of muscle pain, and the range of drugs that can cause muscle side effects is constantly expanding. In this article, the authors comprehensively discuss the diagnostic and therapeutic process in patients with myalgia, and present the spectrum of drug-induced myopathies. The review provides a detailed analysis of the literature on the incidence of myopathy during treatment with hypolipemic drugs, beta-blockers, amiodarone, colchicine, glucocorticosteroids, antimalarials, cyclosporine, zidovudine, and checkpoint inhibitors, a group of drugs increasingly used in the treatment of malignancies. The article considers the clinical course of the different types of myopathies, their pathogenesis, histopathological features, and treatment methods of these disorders. The aim of this paper is to gather from the latest available literature up-to-date information on the course, pathophysiology, and therapeutic options of drug-induced myopathies, to systematize the knowledge of drug-induced myopathies and to draw the attention of internists to the fact that these clinical issues are an important therapeutic problem.

Low-dose atorvastatin therapy induced rhabdomyolysis in a liver cirrhosis patient - a case report

Introduction

Rhabdomyolysis may arise due to traumatic or non-traumatic causes leading to muscle injury. However, increased statin use has raised drug-related side effects like statin-related muscle damage.

Case report

A 74-year-old male with liver cirrhosis secondary to alcohol was prescribed atorvastatin for hyperlipidemia. He developed muscle tenderness and decreased muscle power 2 weeks following statin therapy, evident with a creatine phosphokinase level of more than 22 000 IU/l. The urinalysis also revealed positive for blood. Hence, atorvastatin was ceased. The patient's laboratory parameters improved significantly, implying atorvastatin is the causative agent for rhabdomyolysis.

Discussion

Statins are usually safe and well-tolerated drugs; however, skeletal muscle symptoms occur in ~5-10% of patients. The risk factor for statin-induced muscle injury includes advanced age, drug-altering statin plasma level, liver disease, or chronic kidney disease. Moreover, the hepatic level of CYP450 and its CYP3A4 isoform are altered in chronic liver diseases. CYP3A4 isoenzyme and its activity declines in hepatic cirrhosis patients.

Conclusion

Statins are generally prescribed for hyperlipidemia and primary and secondary prevention in high-risk cardiovascular diseases. However, several risk factors alter statin metabolism, causing statin-induced muscle injury. Thus, despite several studies suggesting otherwise, special precautions should be taken in patients with chronic liver disease.

Virtual Screening of Novel 24-Dehydroxysterol Reductase (DHCR24) Inhibitors and the Biological Evaluation of Irbesartan in Cholesterol-Lowering Effect

Hyperlipidemia is a risk factor for the development of fatty liver and cardiovascular diseases such as atherosclerosis and coronary heart disease, and hence, cholesterol-lowering drugs are considered important and effective in preventing cardiovascular diseases. Thus, researchers in the field of new drug development are endeavoring to identify new types of cholesterol-lowering drugs. 3β-hydroxysterol-Δ(24)-reductase (DHCR24) catalyzes the conversion of desmosterol to cholesterol, which is the last step in the cholesterol biosynthesis pathway. We speculated that blocking the catalytic activity of DHCR24 could be a novel therapeutic strategy for treating hyperlipidemia. In the present study, by virtually screening the DrugBank database and performing molecular dynamics simulation analysis, we selected four potential DHCR24 inhibitor candidates: irbesartan, risperidone, tolvaptan, and conivaptan. All four candidates showed significant cholesterol-lowering activity in HepG2 cells. The experimental mouse model of hyperlipidemia demonstrated that all four candidates improved high blood lipid levels and fat vacuolation in the livers of mice fed with a high-fat diet. In addition, Western blot analysis results suggested that irbesartan reduced cholesterol levels by downregulating the expression of the low-density lipoprotein receptor. Finally, the immune complex activity assay confirmed the inhibitory effect of irbesartan on the enzymatic activity of DHCR24 with its half-maximal inhibitory concentration (IC50) value of 602 nM. Thus, to the best of our knowledge, this is the first study to report that blocking the enzymatic activity of DHCR24 via competitive inhibition is a potential strategy for developing new cholesterol-lowering drugs against hyperlipidemia or multiple cancers. Furthermore, considering that irbesartan is currently used to treat hypertension combined with type 2 diabetes, we believe that irbesartan should be a suitable choice for patients with both hypertension and hyperlipidemia.

Statin Induced Myopathy Among Patients Attending the National Center for Diabetes, endocrinology, & genetics

Background and objectives

myopathy is a major side effect of statins that leads to statin intolerance and discontinuation. In this prospective cohort study, the main objective was to estimate the incidence of myopathy in patients receiving statins. In addition, we identified some risk factors associated with statin induced myopathy.

Methods

A prospective cohort study was conducted at the National Center for Diabetes, Endocrinology and Genetics [NCDEG] in Jordan from October 1, 2018 to January 31, 2021. All subjects who initiated statin therapy followed up during that period. Data was collected at time 0 (baseline), 3, 6, 9, and 12 months after enrollment. Demographic and clinical data were collected from medical records. Muscular symptoms were collected by conducting face-to-face interviews to all patients using a pre-structured questionnaire.

Results

The overall incidence of myopathy among patients taking statins was 27.8%, 31.4% in males and 22.6% in females, the incidence of myopathy was higher in older people, being highest in patients ≥60 years (34%). Bivariate analyses showed no significant association between myopathy and hypothyroidism, diabetes or medications that are known to interact with statins. The incidence of myopathy was highest with Simvastatin 40 mg (50%) and lowest with Fluvastatin XL 80 mg (8%) and Rosuvastatin 10 mg (10.8%).

Conclusions

The overall incidence of myopathy in patients taking statins was 27.8%. Myopathy was directly related to dose and type of statin used. The use of Fluvastatin XL 80 mg and Rosuvastatin 10 mg showed less incidence of myopathy compared with other statins.

•

Myopathy is the most common adverse effect associated with statins therapy.

•

In this prospective cohort study, we estimated the incidence of myopathy among 400 subjects received statin therapy over 1 year follow-up.

•

The overall incidence of myopathy among patients received statins was 27.8%.

•

The incidence of myopathy was highest with Simvastatin 40 mg (50%) and lowest with Fluvastatin XL 80 mg (8%) and Rosuvastatin 10 mg (10.8%).

•

The relatively high rate of statin induced myopathy in our population may point to the importance of genetic factors.

Cholesterol in myasthenia gravis

The cholinergic neuromuscular junction is the paradigm peripheral synapse between a motor neuron nerve ending and a skeletal muscle fiber. In vertebrates, acetylcholine is released from the presynaptic site and binds to the nicotinic acetylcholine receptor at the postsynaptic membrane. A variety of pathologies among which myasthenia gravis stands out can impact on this rapid and efficient signaling mechanism, including autoimmune diseases affecting the nicotinic receptor or other synaptic proteins. Cholesterol is an essential component of biomembranes and is particularly rich at the postsynaptic membrane, where it interacts with and modulates many properties of the nicotinic receptor. The profound changes inflicted by myasthenia gravis on the postsynaptic membrane necessarily involve cholesterol. This review analyzes some aspects of myasthenia gravis pathophysiology and associated postsynaptic membrane dysfunction, including dysregulation of cholesterol metabolism in the myocyte brought about by antibody-receptor interactions. In addition, given the extensive therapeutic use of statins as the typical cholesterol-lowering drugs, we discuss their effects on skeletal muscle and the possible implications for MG patients under chronic treatment with this type of compound.

Pathophysiological mechanisms of statin-associated myopathies: possible role of the ubiquitin-proteasome system

BACKGROUND

Statins are the cornerstone of pharmacotherapy for atherosclerotic cardiovascular disease. While these drugs are generally safe, treatment adherence is not optimal in a considerable proportion of patients because of the adverse effects on skeletal muscles in the forms of myopathy, myalgia, muscular pain, nocturnal muscle cramping, weakness, and rare rhabdomyolysis.

METHODS

For the purpose of this narrative review, we searched for the literature suggesting the involvement of the ubiquitin-proteasome system in the development of statin-induced myopathy.

RESULTS

Statins have been shown to up-regulate the expression of the muscle-specific ubiquitin-proteasome system as the major non-lysosomal intracellular protein degradation system. It has been postulated that statins may provoke instability in the myocyte cell membrane when subjected to eccentric exercise stress, triggering activation of intracellular proteolytic cascades and changes in protein degradation machinery. This is accompanied by the up-regulation of a series of genes implicated in protein catabolism, in addition to those of the ubiquitin-proteasome system.

CONCLUSIONS

Based on the available literature, it seems that the involvement of ubiquitin-proteasome system is potentially implicated in the pathophysiology of statin-induced myopathy.

Understanding medication safety and Charcot-Marie-Tooth disease: a patient perspective

Background Charcot-Marie-Tooth disease is a common inherited neuropathy where patients may be sensitive to adverse effects of certain medicines; however, information about medication safety in this group of people is limited. Objective This study aimed to investigate the experience of Australian individuals with Charcot-Marie-Tooth disease in using medications, including perceived impact of drug-induced adverse effects. Secondarily, it aimed to determine whether individuals with Charcot-Marie-Tooth disease feel adequately supported to make decisions about medication safety. Setting Focus groups and interviews (face-to-face or telephone) of individuals with Charcot-Marie-Tooth disease in Australia. Method A mixed methods qualitative study was conducted between September 2015 and August 2016 using semi-structured interviews. Thematic analysis of interview transcripts was conducted independently by two researchers using inductive coding until concept saturation was achieved. Main outcome measure Perceptions of medicines safety in people with Charcot-Marie-Tooth disease, including barriers to making informed decisions about medication safety. Results Twenty-four adults with Charcot-Marie-Tooth disease participated. Anaesthetics (18%) and pregabalin (15%) were the medications most frequently reported as impacting on Charcot-Marie-Tooth symptoms. Participants sought medication information primarily from general practitioners or neurologists. The main barriers identified by participants were a perceived poor understanding in non-specialist health professionals about Charcot-Marie-Tooth disease and lack of attention to medication safety concerns in people with Charcot-Marie-Tooth disease; this resulted in dissatisfaction about the advice provided. Many individuals who faced uncertainty in obtaining and understanding medicines information turned to internet resources, peer groups, and use of complementary and alternative medicines to self-manage Charcot-Marie-Tooth exacerbations. Conclusion Participants reported drug-related adverse effects and a difficulty in obtaining safety information about medication. This study highlights the need for improved evidence about medication safety in people with Charcot-Marie-Tooth disease. Development of evidence-based resources, increased awareness amongst health professionals about Charcot-Marie-Tooth disease and a team-based care approach could facilitate shared decisions about medication use for people with Charcot-Marie-Tooth disease.

An updated review of pharmacokinetic drug interactions and pharmacogenetics of statins

INTRODUCTION

Hydroxymethylglutaryl-coenzyme A reductase inhibitors (statins) lower cholesterol synthesis in patients with hypercholesterolemia. Increased statin exposure is an important risk factor for skeletal muscle toxicity. Potent inhibitors of cytochrome P450 (CYP) 3A4 significantly increase plasma concentrations of the active forms of simvastatin, lovastatin, and atorvastatin. Fluvastatin is metabolized by CYP2C9, whereas pravastatin, rosuvastatin, and pitavastatin are unaffected by inhibition by either CYP. Statins also have different affinities for membrane transporters involved in processes such as intestinal absorption, hepatic absorption, biliary excretion, and renal excretion.

AREAS COVERED

In this review, the pharmacokinetic aspects of drug-drug interactions with statins and genetic polymorphisms of CYPs and drug transporters involved in the pharmacokinetics of statins are discussed.

EXPERT OPINION

Understanding the mechanisms underlying statin interactions can help minimize drug interactions and reduce the adverse side effects caused by statins. Since recent studies have shown the involvement of drug transporters such as OATP and BCRP as well as CYPs in statin pharmacokinetics, further clinical studies focusing on the drug transporters are necessary. The establishment of biomarkers based on novel mechanisms, such as the leakage of microRNAs into the peripheral blood associated with the muscle toxicity, is important for the early detection of statin side effects.

Alleviation of Simvastatin-Induced Myopathy in Rats by the Standardized Extract of Ginkgo Biloba (EGb761): Insights into the Mechanisms of Action

Statins are the most widely prescribed cholesterol-lowering drugs to reduce the risk of cardiovascular diseases. Statin-induced myopathy is the major side effect of this class of drugs. Here, we studied whether standardized leaf extracts of ginkgo biloba (EGb761) would improve simvastatin (SIM)-induced muscle changes. Sixty Wistar rats were allotted into six groups: control group, vehicle group receiving 0.5% carboxymethyl cellulose (CMC) for 30 days, SIM group receiving 80 mg/kg/day SIM in 0.5% CMC orally for 30 days, SIM withdrawal group treated with SIM for 16 days and sacrificed 14 days later, and EGb761-100 and EGb761-200 groups posttreated with either 100 or 200 mg/kg/day EGb761 orally. Muscle performance on the rotarod, serum creatine kinase (CK), coenzyme Q10 (CoQ10), serum and muscle nitrite, muscle malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) activities were estimated. Additionally, muscle samples were processed for histopathological evaluation. We found that SIM decreased muscle performance on the rotarod, serum CoQ10, as well as muscle SOD and CAT activities while it increased serum CK, serum and muscle nitrite, as well as muscle MDA levels. SIM also induced sarcoplasmic vacuolation, splitting of myofibers, disorganization of sarcomeres, and disintegration of myofilaments. In contrast, posttreatment with EGb761 increased muscle performance, serum CoQ10, as well as muscle SOD and CAT activities while it reduced serum CK as well as serum and muscle nitrite levels in a dose-dependent manner. Additionally, EGb761 reversed SIM-induced histopathological changes with better results obtained by its higher dose. Interestingly, SIM withdrawal increased muscle performance on the rotarod, reduce serum CK and CoQ10, and reduced serum and muscle nitrite while it reversed SIM-induced histopathological changes. However, SIM withdrawal was not effective enough to restore their normal values. Additionally, SIM withdrawal did not improve SIM-induce muscle MDA, SOD, or CAT activities during the period studied. Our results suggest that EGb761 posttreatment reversed SIM-induces muscle changes possibly through its antioxidant effects, elevation of CoQ10 levels, and antagonizing mitochondrial damage.

Influence of Drug-Drug Interactions on the Pharmacokinetics of Atorvastatin and Its Major Active Metabolite ortho-OH-Atorvastatin in Aging People Living with HIV

Background

People living with HIV (PLWH) are aging and experience age-related physiological changes and comorbidities. Atorvastatin is a widely prescribed lipid-lowering agent metabolized by cytochrome P450 (CYP) 3A4, whose hepatocyte uptake is facilitated by organic anion transporting polypeptide (OATP) 1B1/1B3. Inhibition or induction of this enzyme and hepatic transporter can increase or decrease atorvastatin exposure, respectively.

Objective

This study aimed to describe the pharmacokinetic profile of atorvastatin and its major metabolite, and to evaluate drug–drug interactions (DDIs) with antiretrovirals (ARVs).

Methods

The atorvastatin pharmacokinetic profile was best described by a two-compartment model with first-order absorption and elimination. Metabolite concentrations were described by considering both linear metabolism from atorvastatin and presystemic metabolism. The influence of demographic and clinical covariates on drug and metabolite pharmacokinetics was assessed using NONMEM^®. Model-based simulations were performed to evaluate the magnitude of DDIs with ARVs.

Results

Full pharmacokinetic profiles (98 atorvastatin + 62 o-OH-atorvastatin concentrations) and sparse concentrations (78 and 53 for atorvastatin and o-OH-atorvastatin, respectively) were collected in 59 PLWH. Interindividual variability was high. The coadministration of boosted ARVs decreased atorvastatin clearance by 58% and slowed down o-OH-atorvastatin formation by 88%. Atorvastatin clearance increased by 78% when coadministered with CYP3A4 inducers. Simulations revealed a 180% increase and 44% decrease in atorvastatin exposure (area under the curve) in the presence of ARVs with inhibiting and inducing properties, respectively.

Conclusion

This study showed an important interindividual variability in atorvastatin pharmacokinetics that remains largely unexplained after the inclusion of covariates. Since boosted ARVs double atorvastatin exposure, the initial dosage might be reduced by half, and titrated based on individual clinical targets.

Electronic supplementary material

The online version of this article (10.1007/s40262-020-00876-0) contains supplementary material, which is available to authorized users.

Muscle Toxicity of Drugs: When Drugs Turn Physiology into Pathophysiology

Drugs are prescribed to manage or prevent symptoms and diseases, but may sometimes cause unexpected toxicity to muscles. The symptomatology and clinical manifestations of the myotoxic reaction can vary significantly between drugs and between patients on the same drug. This poses a challenge on how to recognize and prevent the occurrence of drug-induced muscle toxicity. The key to appropriate management of myotoxicity is prompt recognition that symptoms of patients may be drug related and to be aware that inter-individual differences in susceptibility to drug-induced toxicity exist. The most prevalent and well-documented drug class with unintended myotoxicity are the statins, but even today new classes of drugs with unintended myotoxicity are being discovered. This review will start off by explaining the principles of drug-induced myotoxicity and the different terminologies used to distinguish between grades of toxicity. The main part of the review will focus on the most important pathogenic mechanisms by which drugs can cause muscle toxicity, which will be exemplified by drugs with high risk of muscle toxicity. This will be done by providing information on key clinical and laboratory aspects, muscle electromyography patterns and biopsy results, and pathological mechanism and management for a specific drug from each pathogenic classification. In addition, rather new classes of drugs with unintended myotoxicity will be highlighted. Furthermore, we will explain why it is so difficult to diagnose drug-induced myotoxicity, and which tests can be used as a diagnostic aid. Lastly, a brief description will be given of how to manage and treat drug-induced myotoxicity.

Statins enhance efficacy of venetoclax in blood cancers

Statins have shown promise as anticancer agents in experimental and epidemiologic research. However, any benefit that they provide is likely context-dependent, for example, applicable only to certain cancers or in combination with specific anticancer drugs. We report that inhibition of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR) using statins enhances the proapoptotic activity of the B cell lymphoma-2 (BCL2) inhibitor venetoclax (ABT-199) in primary leukemia and lymphoma cells but not in normal human peripheral blood mononuclear cells. By blocking mevalonate production, HMGCR inhibition suppressed protein geranylgeranylation, resulting in up-regulation of proapoptotic protein p53 up-regulated modulator of apoptosis (PUMA). In support of these findings, dynamic BH3 profiling confirmed that statins primed cells for apoptosis. Furthermore, in retrospective analyses of three clinical studies of chronic lymphocytic leukemia, background statin use was associated with enhanced response to venetoclax, as demonstrated by more frequent complete responses. Together, this work provides mechanistic justification and clinical evidence to warrant prospective clinical investigation of this combination in hematologic malignancies.

Analysis of secondary care data to evaluate the clinical relevance of the drug-drug interaction between amlodipine and simvastatin

BACKGROUND

Pharmacokinetic analyses revealed an increase in the bioavailability of simvastatin when co-administered with amlodipine [Nishio S et al. Hypertensin research 2005; Son H et al. Drug metabolism and pharmacokinetics 2014]. This may induce an increased risk of muscle toxicity for patients who receive this combination. So far, no in vivo data on the clinical relevance of this interaction exist. The objective of the present analysis was to determine the number of patients with concomitant treatment of amlodipine and simvastatin. Subsequently, the data was analyzed for the indication of muscular discomfort. Patients with combined prescription of amlodipine and another hydroxymethylglutaryl-CoA-reductase inhibitor except simvastatin or patients receiving simvastatin without amlodipine served as control groups.

METHODS

The present analysis used secondary data from the health insurance company AOK PLUS including information regarding diagnosis and drug prescriptions.

RESULTS

In total, 67.081 patients corresponding to 4.93% of the analyzed collective received a combined prescription of amlodipine and simvastatin. The absolute frequency increased continuously over time. Muscular discomfort was detected in a) 6.20% of the patients receiving amlodipine and simvastatin, b) 6.60% of the patients receiving amlodipine and another hydroxymethylglutaryl-CoA- reductase inhibitor and c) 8.04% of the patients with simvastatin only.

CONCLUSIONS

The present analysis shows an increasing trend of combined prescriptions of amlodipine and simvastatin. Evidence for simvastatin dose adaptation or therapy switch to another hydroxymethylglutaryl-CoA-reductase inhibitor, however, was not found. Muscular discomfort does not occur more often in patients with amlodipine and simvastatin compared to the two control groups. The results of the present analysis reveal no evidence for a clinically relevant interaction between amlodipine and simvastatin.

Impact of pharmacogenetics on statin-induced myopathy in South-Indian subjects

OBJECTIVES

Statins are the most commonly prescribed medications for the treatment of atherosclerotic cardiovascular disease. Statin-associated adverse effects occur in ∼10% of patients and are associated with polymorphisms in several key genes coding for transporters and metabolizing enzymes that affect statin pharmacokinetics. In the present study, we examine the association between cytochrome P450 3A5*3 (CYP3A5*3) T>C (rs776746), COQ G>C (rs4693075), and SLCO1B1 T>C (rs4149056) genetic variants with the risk of myopathy in South Indian patients on statin therapy.

METHODS

A total of 202 patients on atorvastatin or rosuvastatin therapy for 12 years were recruited in the study. Genotyping of drug metabolic CYP3A5*3 gene variant and drug transporter genes COQ G>C (rs4693075) and SLCO1B1 T>C (rs4149056) was analyzed by Sanger's sequencing.

RESULTS

In our study subjects, the percentage of patients diagnosed to have statin-induced myopathy was 18%. The majority of the patients were on 10 mg/day dose of either atorvastatin or rosuvastatin. The homozygous nonexpressors genotype CYP3A5*3/3 frequency of the CYP3A5 polymorphism was higher in patients with myopathy. But we could not find association of CYP3A5, COQ, and SLCO1B1 gene polymorphisms with either rosuvastatin or atorvastatin.

CONCLUSION

Our results clearly demonstrate that the frequency of CYP3A5*3 splicing variant is higher in myopathy group than in the tolerant group. We did not find significant association of genetic polymorphisms in CYP3A5, COQ, and SLCO1B1 with atorvastatin- or rosuvastatin-induced myopathy.

Vitamin D supplementation improves simvastatin-mediated decline in exercise performance: A randomized double-blind placebo-controlled study

BACKGROUND

The aim of the present study was to determine the effect of vitamin D supplementation on simvastatin-mediated changes in cardiorespiratory fitness and skeletal muscle mitochondrial content after exercise in adults with type 2 diabetes mellitus (T2DM).

METHODS

Vitamin D-deficient T2DM patients aged 25-50 years performed moderate intensity aerobic exercise for 12 weeks and were randomized to receive simvastatin 40 mg daily, simvastatin 40 mg daily plus vitamin D 60 000 units once weekly, or vitamin D 60 000 units once weekly. The primary outcomes were cardiorespiratory fitness (peak oxygen consumption) and skeletal muscle mitochondrial content (citrate synthase activity in the vastus lateralis) following simvastatin and/or vitamin D replacement therapy.

RESULTS

Twenty-eight patients completed the study. Cardiorespiratory fitness decreased by 8.4% (P < 0.05) following 12 weeks of simvastatin therapy. Vitamin D supplementation blunted the decline in cardiorespiratory fitness to 0.6% (P < 0.05 for between-group difference in change from baseline). Similarly, skeletal muscle mitochondrial content decreased by 3.6% with simvastatin, but improved by 12.1% on supplementation with vitamin D, although the between-group difference was not significant. Vitamin D alone increased cardiorespiratory fitness and mitochondrial content by 7.1% (P < 0.05) and 16.7%, respectively.

CONCLUSIONS

Simvastatin tends to cause deterioration in exercise-associated cardiorespiratory fitness and skeletal muscle mitochondrial content in adults with T2DM, which is blunted by vitamin D supplementation.

Statin-Associated Myopathy in a Pediatric Preventive Cardiology Practice

OBJECTIVES

To describe muscle-related statin adverse effects in real-world pediatric practice.

STUDY DESIGN

Using prospectively collected quality improvement data from a pediatric preventive cardiology practice, we compared serum creatine kinase (CK) levels among patients prescribed and not prescribed statins, and pre-/poststatin initiation. Multivariable mixed-effect models were constructed accounting for repeated measures, examining the effect of statins on log-transformed CK (lnCK) levels adjusted for age, sex, weight, season, insurance type, and race/ethnicity.

RESULTS

Among 1501 patients seen over 3.5 years, 474 patients (14?±?4 years, 47% female) had at least 1 serum CK measured. Median (IQR) CK levels of patients prescribed (n?=?188 patients, 768 CK measurements) and not prescribed statins (n?=?351 patients, 682 CK measurements) were 107 (83) IU/L and 113 (81) IU/L, respectively. In multivariable-adjusted models, lnCK levels did not differ based on statin use (??=?0.02 [SE 0.05], P?=?.7). Among patients started on statins (n?=?86, 130 prestatin and 292 poststatin CK measurements), median CK levels did not differ in adjusted models (? for statin use on lnCK?=?.08 [SE .07], P?=?.2). There was a clinically insignificant increase in CK over time (??=?.08 [SE .04], P?=?.04 per year). No muscle symptoms or rhabdomyolysis were reported among patients with high CK levels.

CONCLUSIONS

In a real-world practice, pediatric patients using statins did not experience higher CK levels, nor was there a meaningful CK increase with statin initiation. These data suggest the limited utility to checking CK in the absence of symptoms, supporting current guidelines.

Large Copy-Number Variations in Patients With Statin-Associated Myopathy Affecting Statin Myopathy-Related Loci

Some patients are susceptible to statin-associated myopathy (SAM) either because of genetic variations affecting statin uptake and metabolism, or because they predispose their carriers to muscular diseases. Among the frequent variants examined using the genome-wide association study approach, SLCO1B1 c.521T>C represents the only validated predictor of SAM in patients treated with high-dose simvastatin. Our aim was to ascertain the overall contribution of large copy-number variations (CNVs) to SAM diagnosed in 86 patients. CNVs were detected by whole genome genotyping using Illumina HumanOmni2.5 Exome BeadChips. Exome sequence data were used for validation of CNVs in SAM-related loci. In addition, we performed a specific search for CNVs in the SLCO1B region detected recently in Rotor syndrome subjects. Rare deletions possibly contributing to genetic predisposition to SAM were found in two patients: one removed EYS associated previously with SAM, the other was present in LARGE associated with congenital muscular dystrophy. Another two patients carried deletions in CYP2C19, which may predispose to clopidogrel-statin interactions. We found no common large CNVs potentially associated with SAM and no CNVs in the SLCO1B locus. Our findings suggest that large CNVs do not play a substantial role in the etiology of SAM.

The Impact of Exercise on Statin-Associated Skeletal Muscle Myopathy

HMG-CoA reductase inhibitors (statins) are the most effective pharmacological means of reducing cardiovascular disease risk. The most common side effect of statin use is skeletal muscle myopathy, which may be exacerbated by exercise. Hypercholesterolemia and training status are factors that are rarely considered in the progression of myopathy. The purpose of this study was to determine the extent to which acute and chronic exercise can influence statin-induced myopathy in hypercholesterolemic (ApoE^-/-) mice. Mice either received daily injections of saline or simvastatin (20 mg/kg) while: 1) remaining sedentary (Sed), 2) engaging in daily exercise for two weeks (novel, Nov), or 3) engaging in daily exercise for two weeks after a brief period of training (accustomed, Acct) (2x3 design, n = 60). Cholesterol, activity, strength, and indices of myofiber damage and atrophy were assessed. Running wheel activity declined in both exercise groups receiving statins (statin x time interaction, p<0.05). Cholesterol, grip strength, and maximal isometric force were significantly lower in all groups following statin treatment (statin main effect, p<0.05). Mitochondrial content and myofiber size were increased and 4-HNE was decreased by exercise (statin x exercise interaction, p<0.05), and these beneficial effects were abrogated by statin treatment. Exercise (Acct and Nov) increased atrogin-1 mRNA in combination with statin treatment, yet enhanced fiber damage or atrophy was not observed. The results from this study suggest that exercise (Nov, Acct) does not exacerbate statin-induced myopathy in ApoE^-/- mice, yet statin treatment reduces activity in a manner that prevents muscle from mounting a beneficial adaptive response to training.

The Toxicology of HMG—CoA Reductase Inhibitors: Prediction of Human Risk

The discovery that 3-hydroxy-3-methyglutaryl coenzyme A reductase was a rate-determining step in the biosynthesis of cholesterol led to the discovery of inhibitors of this enzyme. To support the development of these agents (statins) as potential hypocholesterolemic drugs, a variety of preclinical studies were conducted in several animal species. Not unexpectedly due to the central role played by mevalonic acid and its products including cholesterol in development and maintenance of cellular homeostasis, administration of high dosage levels of these agents led to the expression of a broad variety of adverse effects in many different tissues. Using the tools of toxicologic pathology and classical risk assessment, these varied toxicities were evaluated by many groups relative to the conditions of use in human therapy and a perspective was developed on potential human risk. These approaches of mechanism-based risk assessment predicted that most of the adverse effects observed in animals would not be seen under conditions of human use and supported the successful introduction of one of the most important classes of human medicines.

Characterization of Statin-Associated Myopathy Case Reports in Thailand Using the Health Product Vigilance Center Database

BACKGROUND

HMG-CoA reductase inhibitors [statins], a widely prescribed cholesterol-lowering therapy, are associated with muscle-related adverse events. While characteristics of such events are well documented in Western countries, little data exists for the Thai population.

OBJECTIVE

The aim of this study was to determine the characteristics of patients, type and dosing of statin, and to identify patterns of drug use that may be associated with such adverse events using the national pharmacovigilance database known as Thai Vigibase.

METHOD

Muscle-related adverse events involving statins in the Thai Vigibase from 1996 to December 2009 were identified. For each report, the following information was extracted: patient demographics, co-morbidities, detailed information of adverse event, detailed information of suspected drug, treatment and outcome, as well as causality assessment and quality of reports. Descriptive statistics were performed for all study variables.

RESULTS

A total of 198 cases of statin-associated muscle-related adverse events were identified. Mean age was 61.4 ± 12.4 years of age and 59.6% were female. Simvastatin, atorvastatin, rosuvastatin and cerivastatin were implicated as the suspected drug in 163 (82.3%), 24 (12.1%), 10 (5.1%) and 1 (0.5%) cases, respectively. Rhabdomyolysis accounted for 55.6% of all muscle-related adverse events. Drug interactions known to enhance such toxicity of statins were identified in 40.9% of the total set of reports. Similar to studies from Western countries, fibrates, HIV protease inhibitors, non-dihydropyridine calcium channel blockers, azole antifungals and macrolides were commonly found in such cases. Interestingly, colchicine has been identified as the second most common drug interaction in our database. Case fatality rates were 0.9, 1.6 and 16.7%, when there were 0, 1 and ≥2 interacting drugs, respectively.

CONCLUSIONS

Characteristics of muscle-related adverse events with statins in the Thai population showed some similarities and differences compared with Western countries. Such similarities included advanced age, female sex, certain co-morbidities and drug interactions. While the majority of interacting drugs are well known, a big proportion of cases of statin-colchicine interaction attributed to long-term use of colchicine in Thailand was noted and should be further investigated. Based on these results, an attempt to avoid dangerous and well-known drug interactions among statin users should be implemented nationwide.

A Peculiar Formula of Essential Amino Acids Prevents Rosuvastatin Myopathy in Mice

AIMS

Myopathy, characterized by mitochondrial oxidative stress, occurs in ∼10% of statin-treated patients, and a major risk exists with potent statins such as rosuvastatin (Rvs). We sought to determine whether a peculiar branched-chain amino acid-enriched mixture (BCAAem), found to improve mitochondrial function and reduce oxidative stress in muscle of middle-aged mice, was able to prevent Rvs myopathy.

RESULTS

Dietary supplementation of BCAAem was able to prevent the structural and functional alterations of muscle induced by Rvs in young mice. Rvs-increased plasma 3-methylhistidine (a marker of muscular protein degradation) was prevented by BCAAem. This was obtained without changes of Rvs ability to reduce cholesterol and triglyceride levels in blood. Rather, BCAAem promotes de novo protein synthesis and reduces proteolysis in cultured myotubes. Morphological alterations of C2C12 cells induced by statin were counteracted by amino acids, as were the Rvs-increased atrogin-1 mRNA and protein levels. Moreover, BCAAem maintained mitochondrial mass and density and citrate synthase activity in skeletal muscle of Rvs-treated mice beside oxygen consumption and ATP levels in C2C12 cells exposed to statin. Notably, BCAAem assisted Rvs to reduce oxidative stress and to increase the anti-reactive oxygen species (ROS) defense system in skeletal muscle. Innovation and Conclusions: The complex interplay between proteostasis and antioxidant properties may underlie the mechanism by which a specific amino acid formula preserves mitochondrial efficiency and muscle health in Rvs-treated mice. Strategies aimed at promoting protein balance and controlling mitochondrial ROS level may be used as therapeutics for the treatment of muscular diseases involving mitochondrial dysfunction, such as statin myopathy. Antioxid. Redox Signal. 25, 595-608.

Rhabdomyolysis in a patient taking nebivolol

β Blockers such as propranolol and labetalol are known to induce toxic myopathy because of their partial β₂ adrenoceptor agonistic effect. Nebivolol has the highest β₁ receptor affinity among β blockers, and it has never been reported to induce rhabdomyolysis until now. We report a patient who developed rhabdomyolysis after changing medication to nebivolol. A 75-year-old woman was admitted to our hospital because of generalized weakness originating 2 weeks before visiting. Approximately 1 month before her admission, her medication was changed from carvedilol 12.5 mg to nebivolol 5 mg. Over this time span, she had no other lifestyle changes causing rhabdomyolysis. Her blood chemistry and whole body bone scan indicated rhabdomyolysis. We considered newly prescribed nebivolol as a causal agent. She was prescribed carvedilol 12.5 mg, which she was previously taking, instead of nebivolol. She was treated by hydration and urine alkalization. She had fully recovered and was discharged.

Rhabdomyolysis Due to Combined Therapy with Cerivastatin and Diclofenac

Objective:

To describe the occurrence of severe rhabdomyolysis and acute renal failure in a patient treated concomitantly with cerivastatin and diclofenac.

Case Summary:

A 73-year-old white man with mild chronic renal failure, treated with cerivastatin for hypercholesterolemia, received intramuscular injections of diclofenac for low-back pain. A few days later, severe muscle weakness and acute renal failure developed. Laboratory tests confirmed severe rhabdomyolysis. Diclofenac and cerivastatin were discontinued, and treatment with forced diuresis and urine alkalinization was started. Twenty-four days later, serum creatine phosphokinase and urinary function returned to baseline, and the muscle weakness improved.

Discussion:

Rhabdomyolysis is a well-known adverse effect of statins. According to recent reports, it occurs more frequently with cerivastatin than with other statins. Nevertheless, the interaction between cerivastatin (or other statins) and diclofenac as a trigger for rhabdomyolysis has never been reported.

Conclusions:

Coadministration of diclofenac (and perhaps other nonsteroidal antiinflammatory drugs) with cerivastatin (and perhaps other statins) should be done cautiously, especially in the presence of renal failure, under close monitoring of renal function and muscle enzyme levels.

Ciprofloxacin and statin interaction: a cautionary tale of rhabdomyolysis

A 62-year-old woman presented to hospital, on general practitioner (GP) advice, with a 15-day history of slowly progressing muscle weakness. Results showed newly deranged liver function and creatine kinase (CK) of >24 000. Prior medical history includes previous myocardial infarction and recurrent urinary tract infection. 4 days prior to symptom onset, the patient developed typical urinary tract infection symptoms, treated with ciprofloxacin. The patient had been taking simvastatin (40 mg nocte) for 13 years and had never previously taken ciprofloxacin. Initial management included intravenous crystalloid fluids and discontinuation of simvastatin. CK level fell, liver function slowly improved and renal function remained stable. Muscle weakness improved and the patient became independently able to perform activities of daily living. While the interactions between statins and other antibiotics are well documented, the interaction between statins and ciprofloxacin is less so. The consequences of this interaction can have potentially serious outcomes.

Statin-Induced Myopathy: The Two Faces of Janus

Statins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) have been shown to be effective at lowering low-density lipoprotein cholesterol and decreasing the risk of coronary heart disease. Although safe and well tolerated by most patients, statins have also been associated with muscle-related adverse events. This article reviews statin-associated myotoxicity to clarify the definitions of muscle-related adverse events and discusses their incidences in major statin trials, case reports, and review articles through January 2006. Milder complaints (ie, myalgia) are reported by approximately 5% to 7% of patients who take statins. More severe myotoxicity, namely rhabdomyolysis, is extremely rare for all statins save cerivastatin, and most recent estimates of its incidence are between 0.44 and 0.54 cases per 10 000 person-years. The mechanism of statin-associated myotoxicity has not been satisfactorily defined and is likely due to multiple factors, including membrane instability, mitochondrial dysfunction, and defects in myocyte duplication

Rare variants in known and novel candidate genes predisposing to statin-associated myopathy

AIM

Genetic variants affecting statin uptake, metabolism or predisposing to muscular diseases may confer susceptibility to statin-induced myopathy. Besides the SLCO1B1 rs4149056 genotype, common genetic variants do not seem to determine statin-associated myopathy. Here we aimed to address the potential role of rare variants.

METHODS

We performed whole exome sequencing in 88 individuals suffering from statin-associated myopathy and assessed the burden of rare variants using candidate-gene and exome-wide association analysis.

RESULTS

In the novel candidate gene CLCN1, we identified a heterozygote truncating mutation p.R894* in four patients. In addition, we detected predictably pathogenic case-specific variants in MYOT, CYP3A5, SH3TC2, FBXO32 and RBM20.

CONCLUSION

These findings support the role of rare variants and nominate loci for follow-up studies.

Interventions for Extracranial Carotid Artery Stenosis: An Update

OPINION STATEMENT

Clinical trials demonstrate that stroke risk after the periprocedural period is similar for carotid angioplasty and stenting (CAS) and carotid endarterectomy (CEA), making CAS an acceptable alternative to CEA. However, there tends to be a higher procedural risk of stroke for CAS than for CEA and a potentially higher rate of myocardial infarction in patients undergoing CEA as compared to CAS. Furthermore, lower rates of complications with revascularization and of post-revascularization stroke have been attributed to advances in medical management, improved surgical technique, and new devices. We discuss identifying patients who may have higher complication rates and recent clinical studies and medical advances directed at reducing stroke risk in patients with extracranial carotid stenosis.

Statins and the neuromuscular system: a neurologist's perspective

Statins intolerance is mainly due to their side effects on the neuromuscular system (primarily muscle). It has become an important issue because of the major cardiovascular risk reduction of this class of drugs. However, the facts related to these side effects are sometimes under-recognized or controversial. A literature review of the recent developments in the field is given. The clinical definition of statin myopathy and its presentation are not suitable for the myology field. Management and prevention are not validated. More genetic risk factors need to be established. Neurologists should become more involved in statin intolerance evaluation and management.

Rhabdomyolysis in the setting of induced hypothyroidism and statin therapy: a case report

Mild elevation of creatine kinase (CK) is common in untreated hypothyroidism, but severe myositis and overt rhabdomyolysis are rare. Similarly, muscle pain and CK elevation are potential side effects of statin therapy, yet rhabdomyolysis is likewise rare in the absence of medication interactions adversely affecting statin metabolism. The coexistence of statin therapy and hypothyroid states may synergistically increase the risk of myopathy. We describe a case of rhabdomyolysis attributable to induced hypothyroidism in a patient on chronic statin medication who was anticipating adjuvant radioiodine ((131)I) therapy for a thyroid carcinoma.

Statin-associated Autoimmune Myopathies: A Pathophysiologic Spectrum

Background

Statins have recently been reported to cause a rare autoimmune inflammatory and/or necrotic myopathy that begins or persists after drug cessation.

Methods

We report on 26 patients seen at a neuromuscular centre between 2005 and 2011 who demonstrated muscle weakness/myalgias and creatine kinase elevations during or after statin treatment with continuation of signs and symptoms despite statin withdrawal.

Results

All patients were treated with immunosuppressive therapy with good response; all improved biochemically and 86% improved clinically. Sixty-five percent of patients who attempted to taper off immunosuppressive therapy relapsed. We report on a novel finding whereby five of the seven patients who underwent multiple biopsies throughout their disease demonstrated a transformation of their histological diagnosis, with four progressing from having myofibre necrosis with minimal or no inflammation to a diagnosis of polymyositis.

Conclusions

This study offers preliminary evidence that statin-associated necrotizing myopathy and statin-associated polymyositis may not be separate entities but are part of the same pathophysiological spectrum. Both entities respond well to immunosuppression.

Understanding patients' perspective of statin therapy: can we design a better approach to the management of dyslipidaemia? A literature review

INTRODUCTION

Dyslipidaemia leads to atherosclerosis and is a major risk factor for cardiovascular diseases. In clinical trials, 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors, or statins, have been shown to effectively reduce dyslipidaemia. Despite the availability and accessibility of statins, myocardial infarctions and cerebrovascular accidents remain among the top causes of mortality in developed countries, including Singapore. This enigma could be attributed to suboptimal adherence to statin therapy. The present literature review aimed to evaluate patients' perceptions of statin therapy.

METHODS

We searched PubMed and other databases for articles published in English from October 1991 to May 2012 containing keywords such as 'patient', 'views', 'perceptions', 'adherence', 'statin' and 'dyslipidaemia'. Of the 122 eligible studies retrieved, 58 were reviewed. The findings were categorised and framed in accordance with the Health Belief Model.

RESULTS

Patients with dyslipidaemia appeared to underestimate their susceptibility to dyslipidaemia-related complications, partly due to their demographic profiles. Failure to appreciate the severity of potential complications was a major hindrance toward adherence to statin therapy. Other factors that affected a patient's adherence included lack of perceived benefits, perceived side effects, the cost of statins, poor physician-patient relationship, and overestimation of the effectiveness of diet control as a treatment modality.

CONCLUSION

Existing evidence suggests that the cause of poor adherence to statin therapy is multifactorial. The use of the Health Belief Model to present the results of our literature review provides a systematic framework that could be used to design a patient-centric approach for enhancing adherence to statin therapy.

A systematic review of statin-induced muscle problems in clinical trials

Statin therapy is associated with muscle problems in approximately 10% to 25% of patients treated in clinical practice, but muscle problems have rarely been reported in controlled clinical trials. We performed a systematic search and review of statin clinical trials to examine how these studies evaluated muscle problems and to determine why there are apparent differences in muscle problems between clinical trials and practice. We initially identified 1,012 reports related to clinical trials of statin therapy, 42 of which qualified for analysis. Fifteen, 4, and 22 trials reported creatine kinase values only >10, 5, and 3 times the upper limits of normal, respectively, in both statin- and placebo-treated participants. Four trials reported average creatine kinase values, which increased with statin treatment in 3 instances. Twenty-six trials reported muscle problems, with an average incidence in statin- and placebo-treated participants of 13%, but only one trial specifically queried about muscle problems. Three trials used a run-in period to eliminate participants with statin intolerance and noncompliance. The percentage of muscle problems tended to be higher with statin treatment (12.7%) than with placebo group (12.4%, P = .06). This small difference probably reflects a high background rate of nonspecific muscle problems in both groups that could not be distinguished from statin-associated myalgia because most clinical trials did not use a standard definition for statin myalgia.

How to balance cardiorenometabolic benefits and risks of statins

Statins, 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, are important for preventing adverse cardiovascular events not only in patients with a high risk of vascular disease but also in those with a low risk, by reducing the levels of low-density lipoprotein cholesterol. Statin is associated with deteriorating glucose homeostasis and an increased risk of diabetes mellitus. Moreover, these off-target effects are dose-dependent; it has also been suggested that renal insult can be caused dose-dependently by statin treatment, in contrast to previous studies showing a renoprotective effect. The 2013 American College of Cardiology/American Heart Association guidelines recommend the use of high-intensity statin therapy, and extend its use to more people at risk of vascular diseases. However, a European committee has expressed concerns about the potential side effects of using statins in a large fraction of the population for extended periods. This is true of Asian people, for whom the disease burden from cardiovascular disorders is not as great as among Western ethnic groups. There are still many unanswered questions on how to balance the cardiovascular benefits with the potential renometabolic risks of statins. Therefore, genetic or pharmacogenetic approaches are needed to define who is more vulnerable to developing diabetes mellitus or acute kidney injury. In particular, more information is required regarding the metabolism of statins, and their off-target or unknown actions and overall impact. These different renometabolic effects of statins should help in formulating optimal therapeutic strategies for patients for reducing overall morbidity and mortality and not just those associated with cardiovascular diseases.

Statins and the risk of liver injury: a population-based case-control study

OBJECTIVE

This case-control study investigated the association between statin use and liver injury using Taiwan's National Health Insurance Research Database.

METHODS

Our study subjects included 4165 cases (patients who had been admitted with a primary diagnosis of liver injury between 2002 and 2009) and 16 660 age-matched, sex-matched and index date-matched controls. Multivariable conditional regression models were used to estimate the association between statin use and liver injury.

RESULTS

Users of statins were not associated with risk of liver injury (adjusted odds ratio [aOR] 1.04; 95% confidence interval [0.90-1.19]) when compared with nonusers. Nevertheless, a higher dose of statin (≥1 defined daily dose; aOR 1.55 [1.14-2.11]) and use of rosuvastatin before event of liver injury (aOR 1.38 [1.03-1.85]) were significantly associated with liver injury.

CONCLUSIONS

This population-based study extends previous evidence by exploring the potential association between statins use and risk of liver injury. Overall, we found that statin was not associated with risk of liver injury. Nevertheless, special concern should be paid to those who used statin ≥1 defined daily dose and rosuvastatin.

Dietary modulators of statin efficacy in cardiovascular disease and cognition

Cardiovascular disease remains the leading cause of morbidity and mortality in the United States and other developed countries, and is fast growing in developing countries, particularly as life expectancy in all parts of the world increases. Current recommendations for the prevention of cardiovascular disease issued jointly from the American Academy of Cardiology and American Heart Association emphasize that lifestyle modification should be incorporated into any treatment plan, including those on statin drugs. However, there is a dearth of data on the interaction between diet and statins with respect to additive, complementary or antagonistic effects. This review collates the available data on the interaction of statins and dietary patterns, cognition, genetics and individual nutrients, including vitamin D, niacin, omega-3 fatty acids, fiber, phytochemicals (polyphenols and stanols) and alcohol. Of note, although the available data is summarized, the scope is limited, conflicting and disparate. In some cases it is likely there is unrecognized synergism. Virtually no data are available describing the interactions of statins with dietary components or dietary pattern in subgroups of the population, particularly those who may benefit most were positive effects identified. Hence, it is virtually impossible to draw any firm conclusions at this time. Nevertheless, this area is important because were the effects of statins and diet additive or synergistic harnessing the effect could potentially lead to the use of a lower intensity statin or dose.

Drug-drug interactions between HMG-CoA reductase inhibitors (statins) and antiviral protease inhibitors

The HMG-CoA reductase inhibitors are a class of drugs also known as statins. These drugs are effective and widely prescribed for the treatment of hypercholesterolemia and prevention of cardiovascular morbidity and mortality. Seven statins are currently available: atorvastatin, fluvastatin, lovastatin, pitavastatin, pravastatin, rosuvastatin and simvastatin. Although these drugs are generally well tolerated, skeletal muscle abnormalities from myalgia to severe lethal rhabdomyolysis can occur. Factors that increase statin concentrations such as drug-drug interactions can increase the risk of these adverse events. Drug-drug interactions are dependent on statins' pharmacokinetic profile: simvastatin, lovastatin and atorvastatin are metabolized through cytochrome P450 (CYP) 3A, while the metabolism of the other statins is independent of this CYP. All statins are substrate of organic anion transporter polypeptide 1B1, an uptake transporter expressed in hepatocyte membrane that may also explain some drug-drug interactions. Many HIV-infected patients have dyslipidemia and comorbidities that may require statin treatment. HIV-protease inhibitors (HIV PIs) are part of recommended antiretroviral treatment in combination with two reverse transcriptase inhibitors. All HIV PIs except nelfinavir are coadministered with a low dose of ritonavir, a potent CYP3A inhibitor to improve their pharmacokinetic properties. Cobicistat is a new potent CYP3A inhibitor that is combined with elvitegravir and will be combined with HIV-PIs in the future. The HCV-PIs boceprevir and telaprevir are both, to different extents, inhibitors of CYP3A. This review summarizes the pharmacokinetic properties of statins and PIs with emphasis on their metabolic pathways explaining clinically important drug-drug interactions. Simvastatin and lovastatin metabolized through CYP3A have the highest potency for drug-drug interaction with potent CYP3A inhibitors such as ritonavir- or cobicistat-boosted HIV-PI or the hepatitis C virus (HCV) PI, telaprevir or boceprevir, and therefore their coadministration is contraindicated. Atorvastatin is also a CYP3A substrate, but less potent drug-drug interactions have been reported with CYP3A inhibitors. Non-CYP3A-dependent statin concentrations are also affected although to a lesser extent when coadministered with HIV or HCV PIs, mainly through interaction with OATP1B1, and treatment should start with the lowest available statin dose. Effectiveness and occurrence of adverse effects should be monitored at regular time intervals.

Combination therapy with ezetimibe and simvastatin to achieve aggressive LDL reduction

A low-density lipoprotein (LDL) cholesterol goal of less than 100 mg/dl is recommended for patients at moderate to high risk of cardiovascular disease with an optional LDL goal of less than 70 mg/dl for patients at a very high risk of cardiovascular disease. Most patients will require reductions in LDL of more than 50% in order to achieve these more aggressive goals. Only a few agents will lower LDL by at least 50%. This review will focus on the efficacy and safety ezetimibe/simvastatin coadministered as a therapy with enhanced LDL-lowering efficacy, while minimizing the adverse effects of statins in a wide range of patients. Ezetimibe 10 mg/simvastatin 80 mg lowers LDL by approximately 60% and has been demonstrated to be superior to the highest doses of atorvastatin and rosuvastatin for lowering LDL and raising high-density lipoprotein.

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.

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.