Safety of statins

Comparative study of Lepidium sativum orally administered seeds, hydrogel and atorvastatin on obesity of rats fed on a high fat diet

BACKGROUND

Obesity has become a prevalent issue worldwide, leading to various complications such as hyperlipidemia, diabetes, and cardiovascular problems. Statins, as FDA approved anti-hyperlipidemic drugs, still pose some concerns upon their administration. Recently, researchers have looked for natural products as an alternative to manage hyperlipidemia and obesity.

AIM

This work aimed to study the hypolipidemic effect of Lepidium sativum garden cress (GC) from different preparations; orally administered seeds, and hydrogel, in comparison to atorvastatin.

METHODS

GC hydrogel was prepared from the GC aqueous extract and pharmaceutically evaluated for its pH, spreadability, seeds content, homogeneity, rheology, and in vitro release. The rat's body weight, blood glucose levels, total lipid profile, and liver biomarkers were evaluated on obese rats for one month. In addition, the histopathology study was also performed.

RESULTS

GC hydrogel had acceptable pharmaceutical properties and showed a sustained release performance over 24 h. Oral and topical GC significantly reduced the lipid profiles, blood sugar and ALT, AST levels more than the negative control group and comparable to atorvastatin. It was found that oral GC showed a significant effect on the percentage decrease in the rat's body weight than the applied hydrogel. Histopathology study revealed a better outcome in the histological structure of pancreas and liver compared with rats feed on high fat diet post-treatment for one month.

CONCLUSION

GC orally administered, or topically applied hydrogel could be a promising, safe alternative formulation to atorvastatin in managing hyperlipidemia and normalizing body weight of obese rats.

Differences in susceptibility of HT-29 and A549 cells to statin-induced toxicity: An investigation using high content screening

Statins are a group of hydroxymethylglutaryl coenzyme A reductase inhibitors that are used in the treatment of cardiovascular diseases. However, statins have been found to be cytotoxic, and many unexpected side effects have been reported in clinical applications. The susceptibilities of different cell lines toward statins are diverse, and the mechanisms of cytotoxicity remain unknown. Therefore, the present study aimed to investigate differences in the susceptibility to and mechanisms of statin-induced cytotoxicity in two cell lines, HT-29 and A549, using a high content screening-based multiparametric toxicity assay panel. We found that the two cell types exhibited differing susceptibilities to the cytotoxic effects of the different statins. Additionally, the cytotoxicity was inconsistent between different statins in the two cell lines. Four statins with strong cytotoxicity decreased the viability of HT-29 cells via the mitochondrial pathway, as evidenced by decreased mitochondrial membrane potential, and elevated mitochondrial mass, calcium release and cell apoptosis, and reactive oxygen species. In contrast, these four statins only induced a decrease in the mitochondrial membrane potential in A549 cells. The above results provide an objective reason for future evaluations of cytotoxic differences in cell types and the underlying mechanisms of cytotoxicity in different statins, and provide a good scientific basis for further research on countermeasures against statin-induced cell injuries.

Effect of simvastatin on sensorial, motor, and morphological parameters in sciatic nerve crush induced-neuropathic pain in rats

The present study compares the effects of a low and high doses of simvastatin in a model of peripheral neuropathy by evaluating sensorial, motor, and morphological parameters. First, male Wistar rats were orally treated with vehicle (saline, 1 mL/kg), simvastatin (2 and 80 mg/kg) or morphine (2 mg/kg, s.c.), 1 h before 2.5% formalin injection. Neuropathic pain was induced by crushing the sciatic nerve, and mechanical and cold allodynia, nerve function, histology, MPO and NAG concentrations, as well as mevalonate induced-nociception were evaluated. Animals were orally treated with vehicle, simvastatin, or gabapentin (30 mg/kg) for 18 days. Simvastatin (2 and 80 mg/kg) reduced the inflammatory pain induced by formalin, but failed to decrease the paw edema. Mechanical allodynia was reduced by the simvastatin (2 mg/kg) until the 12th day after injury and until the 18th day by gabapentin. However, both simvastatin and gabapentin treatments failed in attenuated cold allodynia or improved motor function. Interestingly, both doses of simvastatin showed a neuroprotective effect and inhibited MPO activity without altering kidney and hepatic parameters. Additionally, only the higher dose of simvastatin reduced the cholesterol levels and the nociception induced by mevalonate. Our results reinforce the antinociceptive, antiallodynic, and anti-inflammatory effects of oral simvastatin administration, which can strongly contribute to the sciatic nerve morphology preservation. Furthermore, our data suggest that lower and higher doses of simvastatin present beneficial effects that are dependent and independent of the mevalonate pathway, respectively, without causing signs of nerve damage.

Ontology-based systematical representation and drug class effect analysis of package insert-reported adverse events associated with cardiovascular drugs used in China

With increased usage of cardiovascular drugs (CVDs) for treating cardiovascular diseases, it is important to analyze CVD-associated adverse events (AEs). In this study, we systematically collected package insert-reported AEs associated with CVDs used in China, and developed and analyzed an Ontology of Cardiovascular Drug AEs (OCVDAE). Extending the Ontology of AEs (OAE) and NDF-RT, OCVDAE includes 194 CVDs, CVD ingredients, mechanisms of actions (MoAs), and CVD-associated 736 AEs. An AE-specific drug class effect is defined to exist when all the drugs (drug chemical ingredients or drug products) in a drug class are associated with an AE, which is formulated as a new proportional class level ratio (“PCR”) = 1. Our PCR-based heatmap analysis identified many class level drug effects on different AE classes such as behavioral and neurological AE and digestive system AE. Additional drug-AE correlation tests (i.e., class-level PRR, Chi-squared, and minimal case reports) were also modified and applied to further detect statistically significant drug class effects. Two drug ingredient classes and three CVD MoA classes were found to have statistically significant class effects on 13 AEs. For example, the CVD Active Transporter Interactions class (including reserpine, indapamide, digoxin, and deslanoside) has statistically significant class effect on anorexia and diarrhea AEs.

Statin Use and the Risk of Cataracts: A Systematic Review and Meta-Analysis

BACKGROUND

Cataracts are the main cause of poor vision and blindness worldwide. The effects of statin administration on cataracts remain debated. Therefore, we conducted a systematic review and meta-analysis to determine whether statin use affects the risk of cataracts.

METHODS AND RESULTS

We performed a systematic search of the electronic databases PubMed, EMBASE, and the Cochrane Library through January 2016. Weighted averages were reported as relative risk values with 95% CIs. Statistical heterogeneity scores were assessed with the standard Cochran's Q test and the I² statistic. A total of 6 cohort studies, 6 case-control studies, and 5 randomized controlled trials, together involving more than 313 200 patients, were included in our study. The pooled estimates of cohort studies indicated that the use of statins moderately increases the risk of cataracts (relative risk, 1.13; 95% CI, 1.01-1.25). The pooled estimates of case-control studies (relative risk=1.10, 95% CI, 0.99-1.23) and randomized controlled trials (relative risk, 0.89; 95% CI, 0.72-1.10) indicated that the use of statins does not increase the risk of cataracts. The sensitivity analysis confirmed the stability of the results. Heterogeneity was found among the cohort and case-control studies.

CONCLUSIONS

Based on the present meta-analysis of these studies, we could only conclude that there is no clear evidence showing that statin use increases the risk of cataracts. The most likely case is that there is no association between statin use and cataracts. Because of the considerable benefits of statins in cardiovascular patients, this issue should not deter their use.

Treatment of dyslipidemia with statins and physical exercises: recent findings of skeletal muscle responses

Statin treatment in association with physical exercise practice can substantially reduce cardiovascular mortality risk of dyslipidemic individuals, but this practice is associated with myopathic event exacerbation. This study aimed to present the most recent results of specific literature about the effects of statins and its association with physical exercise on skeletal musculature. Thus, a literature review was performed using PubMed and SciELO databases, through the combination of the keywords "statin" AND "exercise" AND "muscle", restricting the selection to original studies published between January 1990 and November 2013. Sixteen studies evaluating the effects of statins in association with acute or chronic exercises on skeletal muscle were analyzed. Study results indicate that athletes using statins can experience deleterious effects on skeletal muscle, as the exacerbation of skeletal muscle injuries are more frequent with intense training or acute eccentric and strenuous exercises. Moderate physical training, in turn, when associated to statins does not increase creatine kinase levels or pain reports, but improves muscle and metabolic functions as a consequence of training. Therefore, it is suggested that dyslipidemic patients undergoing statin treatment should be exposed to moderate aerobic training in combination to resistance exercises three times a week, and the provision of physical training prior to drug administration is desirable, whenever possible.

[Adherence to statin treatment and associated factors in female users from the Unified Health System (SUS)]

OBJECTIVE

To identify the adherence rate of a statin treatment and possible related factors in female users from the Unified Health System.

METHOD

Seventy-one women were evaluated (64.2 ± 11.0 years) regarding the socio-economic level, comorbidities, current medications, level of physical activity, self-report of muscular pain, adherence to the medical prescription, body composition and biochemical profile. The data were analyzed as frequencies, Chi-Squared test, and Mann Whitney test (p<0.05).

RESULTS

15.5% of women did not adhere to the medical prescription for the statin treatment, whose had less comorbidities (p=0.01), consumed less quantities of medications (p=0.00), and tended to be younger (p=0.06). Those patients also presented higher values of lipid profile (CT: p=0.01; LDL-c: p=0.02). Musculoskeletal complains were not associated to the adherence rate to the medication.

CONCLUSION

The associated factors to adherence of dyslipidemic women to statin medical prescription were age, quantity of comorbidities and quantity of current medication.

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.

Statin use and cataract surgery: a nationwide retrospective cohort study in elderly ethnic Chinese patients

BACKGROUND

Since a report of lenticular opacities in dogs treated with high dosages of statins, the debate on the relationship between statin therapy and cataracts has not reached a conclusion.

OBJECTIVE

The aim of this study was to evaluate the association between statin therapy and the risk of cataract surgery in an elderly ethnic Chinese population using time-dependent analysis to minimize immortal time bias.

METHODS

A retrospective cohort study using the Longitudinal Health Insurance Database 2005 randomly sampled from the National Health Insurance Research Database, Taiwan, was conducted. A total of 50,165 adults aged between 65 and 90 years in 1998 without records of statin therapy or diagnosis of cataracts between July 1997 and December 1997 were included in the analysis. The first record of lens extraction within the follow-up period (1998-2009) was set as the study endpoint. A propensity score was derived using a logistic regression model to model the receipt of statin therapy as a function of the baseline characteristics for every subject. We used the time-dependent Cox regression model to test the relative hazard of undergoing cataract surgery between statin users and non-users, while use of statins was treated as a time-dependent variable, controlling for baseline age and individual propensity score.

RESULTS

Of the 50,165 enrolled subjects, 17,670 individuals with an incident lens extraction were identified during a median follow-up of 10.7 years. The incidence of cataract surgery was 49.7/1,000 person-years in the statin-using period compared with 38.5/1,000 person-years in the statin-non-using period. The adjusted hazard ratio of cataract surgery was 1.20 (95 % CI 1.14-1.27; P < 0.001) in statin users compared with statin non-users.

CONCLUSION

Statin therapy was associated with a modestly increased risk of cataract surgery. We suggest regular checks for lens opacity in statin users.

Bioenergetic study of murine hepatic tissue treated in vitro with atorvastatin

Atorvastatin (a 3-hydroxy-3-methylglutaryl coenzyme-A reductase inhibitor) is a widely used cholesterol-lowering drug, which is recognized for its potential hepatotoxicity. This study investigated in vitro effects of this agent on hepatic tissue respiration, ATP content, caspase activity, urea synthesis and histology. Liver fragments from Taylor Outbred and C57Bl/6 mice were incubated at 37°C in Krebs-Henseleit buffer continuously gassed with 95% O₂: 5% CO₂ in the presence and absence of atorvastatin. Phosphorescence O₂ analyzer that measured dissolved [O₂] as a function of time was used to monitor cellular mitochondrial O₂ consumption. The caspase-3 substrate N-acetyl-asp-glu-val-asp-7-amino-4-methylcoumarin was used to monitor caspase activity. The rates of hepatocyte respiration (μM O₂ min^-1 mg^-1) in untreated samples were 0.15 ± 0.07 (n = 31). The corresponding rates for samples treated with 50 nM (therapeutic concentration), 150 nM or 1.0 μM atorvastatin for ≤13 h were 0.13 ± 0.05 (n = 19), p = 0.521. The contents of hepatocyte ATP (pmol^-1 mg^-1) in untreated samples were 40.3 ± 14.0 and in samples treated with 1.0 μM atorvastatin for ≤4.5 h were 48.7 ± 23.9 (p = 0.7754). The concentrations of urea (mg/dL mg^-1, produced over 50 min) for untreated samples were 0.061 ± 0.020 (n = 6) and for samples treated with 1.0 μM atorvastatin for ≤6 h were 0.072 ± 0.022 (n = 6), p = 0.3866. Steadily, hepatocyte caspase activity and histology were unaffected by treatments with up to 1.0 μM atorvastatin for ≤6 h. Thus, the studied murine model showed preserved hepatocyte function and structure in the presence of high concentrations of atorvastatin.

Ezetimibe therapy: mechanism of action and clinical update

The lowering of low-density lipoprotein cholesterol (LDL-C) is the primary target of therapy in the primary and secondary prevention of cardiovascular events. Although statin therapy is the mainstay for LDL-C lowering, a significant percentage of patients prescribed these agents either do not achieve targets with statin therapy alone or have partial or complete intolerance to them. For such patients, the use of adjuvant therapy capable of providing incremental LDL-C reduction is advised. One such agent is ezetimibe, a cholesterol absorption inhibitor that targets uptake at the jejunal enterocyte brush border. Its primary target of action is the cholesterol transport protein Nieman Pick C1 like 1 protein. Ezetimibe is an effective LDL-C lowering agent and is safe and well tolerated. In response to significant controversy surrounding the use and therapeutic effectiveness of this drug, we provide an update on the biochemical mechanism of action for ezetimibe, its safety and efficacy, as well as the results of recent randomized studies that support its use in a variety of clinical scenarios.

Efeito do exercício físico e estatinas na função muscular em animais com dislipidemia

As estatinas são utilizadas no tratamento das dislipidemias, com grande tolerância; no entanto, vários efeitos colaterais podem surgir, destacando-se miopatia. A prática regular do exercício físico (EF) produz modificações favoráveis no perfil lipídico; entretanto, pode gerar lesões musculares. OBJETIVO: Avaliar o efeito da associação entre exercício físico e estatinas na função muscular, pela análise histológica, em modelo experimental animal com dislipidemia. MÉTODOS: Foram utilizados 80 ratos machos Wistar, distribuídos em oito grupos, incluindo animais submetidos à dieta hipercolesterolêmica (DH), sinvastatina com (G1) e sem (G2) EF; DH e fluvastatina, com (G3) e sem EF (G4); alimentados com ração comercial (RC) na presença (G5) e ausência de (G6) EF; DH submetidos (G7) ou não (G8) a EF. A DH foi administrada por 90 dias, as estatinas e prática de EF em esteira rolante por oito semanas. Os animais foram sacrificados, e o músculo sóleo retirado para análise histológica. Aplicaram-se os testes t de Student pareado e análise multivariada, com nível significante para p < 0,05. RESULTADOS: As principais alterações histológicas encontradas foram fibras de diferentes diâmetros, atróficas, em degeneração, splitting, edema, infiltrado inflamatório. Essas alterações foram observadas em 90% dos animais do grupo G1, 80% do G2, 70% do G3, 30% do G4, 40% do G5 e 30% do G7. Nos grupos G6 e G8 identificaram-se fibras musculares com morfologia preservada. CONCLUSÕES: Na avaliação histológica muscular, a associação entre fluvastatina, sinvastatina e exercício físico acarreta alterações morfológicas com predomínio no uso da sinvastatina, variando de grau leve a grave, no músculo sóleo de ratos, induzidos pelos inibidores da HMG-CoA redutase.

Lack of a relationship between circulating gamma-glutamyltransferase levels and carotid intima media thickness in hypertensive and diabetic patients

BACKGROUND

By increasing the intracellular prooxidant burden, gamma-glutamyltransferase (GGT) may accelerate atherosclerotic vascular disease. That noxious influence may be reflected by circulating enzyme levels, a correlate of cardiovascular risk factors, and a predictor of incident events. To evaluate this hypothesis, we tested the association between circulating GGT and common carotid intima-media thickness (CIMT), a surrogate index of systemic atherosclerotic involvement, in a large and well-characterized group of patients at risk of cardiovascular disease (CVD).

PATIENTS

This study analyzed 548 patients with hypertension and/or diabetes and a widely prevalent history of CVD. Subjects with known hepatic disease and abnormal GGT values were excluded.

METHODS

CIMT (B-mode ultrasonography) values were the mean of four far-wall measurements at both common carotids. Metabolic syndrome (MetS) was diagnosed according to National Cholesterol Education Program-Adult Treatment Panel III criteria. Due to inherent sex-related differences in GGT levels, the data were analyzed separately in males and females in samples dichotomized by the median.

RESULTS

The age-adjusted CIMT values did not differ by GGT levels in males or females. In contrast, the carotid wall was consistently thicker in patients with a history of CVD and MetS independent of age and concurrent GGT values. In both sexes, GGT was associated with key components of the MetS such as triglycerides, fasting plasma glucose, and body mass index.

CONCLUSION

The data collected in this mixed group of hypertensive and/or diabetic patients with widely prevalent history of CVD do not support the concept of a direct pathophysiological link between GGT levels within reference limits and atherosclerotic involvement.

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.

Effects of simvastatin and metformin on polycystic ovary syndrome after six months of treatment

CONTEXT

A randomized trial on women with polycystic ovary syndrome (PCOS) compared simvastatin, metformin, and a combination of these drugs.

OBJECTIVE

The aim of the study was to evaluate long-term effects of simvastatin and metformin on PCOS.

DESIGN

Women with PCOS (n = 139) were randomized to simvastatin (S), metformin (M), or simvastatin plus metformin (SM) groups. Evaluations were performed at baseline and at 3 and 6 months.

SETTING

The study was conducted at a university medical center.

PRIMARY OUTCOME

We measured the change of serum total testosterone.

RESULTS

Ninety-seven subjects completed the study. Total testosterone decreased significantly and comparably in all groups: by 25.6, 25.6, and 20.1% in the S, M, and SM groups, respectively. Both simvastatin and metformin improved menstrual cyclicity and decreased hirsutism, acne, ovarian volume, body mass index, C-reactive protein, and soluble vascular cell adhesion molecule-1. Dehydroepiandrosterone sulfate declined significantly only in the S group. Total cholesterol and low-density lipoprotein cholesterol significantly declined only in the S and SM groups. Ongoing reduction of ovarian volume, decreased hirsutism, acne and testosterone were observed between 0 and 3 months as well as between 3 and 6 months. Improvement of lipid profile, C-reactive protein, and soluble vascular cell adhesion molecule-1 occurred only during the first 3 months of treatment, with little change thereafter. Treatments were well tolerated, and no significant adverse effects were encountered.

CONCLUSIONS

Long-term treatment with simvastatin was superior to metformin. Improvement of ovarian hyperandrogenism continued throughout the duration of the study.

Current evidence for perioperative statins in cardiac surgery

Cardiac surgery improves life expectancy and quality of life for the constantly ageing population in developed countries. Mediated by their lipid-dependent and lipid-independent mechanisms, statins are sought to provide benefit with regard to better outcomes after cardiac surgery. Current guidelines recommend statin use in patients undergoing coronary artery bypass grafting, while less evidence is available for patients referred to heart valve surgery. Optimal selection of statin drug and dosage including perioperative timing of statin therapy remains largely unknown, but results of ongoing meta-analyses and future randomized trials will add important evidence to guide perioperative statin treatment of cardiac surgery patients.

Statin myopathy: a lipid clinic experience on the tolerability of statin rechallenge

INTRODUCTION

Statin myopathy is a generally encountered side effect of statin usage. Both muscle symptoms and a raised serum creatine kinase (CK) are used in case definition, but these are common manifestations of other conditions, which may not be statin related. Statin rechallenge assuming no contraindication in selected cases is an option before considering a different class of lipid-lowering agent.

AIMS

We aim to characterize retrospectively the patients referred to our Lipid Clinic with a diagnosis of statin myopathy. The tolerability of different statins was assessed to determine a strategy for rechallenging statins in such patients in the future.

RESULTS

Patients with statin myopathy constitute 10.2% of our Lipid Clinic workload. They are predominantly female (62.0%), Caucasian (63.9%), with a mean age of 58.3 years and mean body mass index (BMI) of 29.3 kg/m(2). The serum CK and erythrocyte sedimentation rate (ESR) were statistically higher compared to patients with statin intolerances with no muscular component or CK elevations. Secondary causes of statin myopathy were implicated in 2.7% of cases. Following statin myopathy to simvastatin we found no statistical difference between the tolerability rates between atorvastatin, rosuvastatin, pravastatin, and fluvastatin. Fibrates, cholestyramine, and ezetimibe were statistically better tolerated in these patients.

CONCLUSIONS

Statin rechallenge is a real treatment option in patients with statin myopathy. Detailed history and examination is required to exclude muscle diseases unrelated to statin usage. In patients developing statin myopathy on simvastatin, we did not find any statistical difference between subsequent tolerability rates to rosuvastatin, pravastatin, and fluvastatin.

Maternal protein restriction elevates cholesterol in adult rat offspring due to repressive changes in histone modifications at the cholesterol 7alpha-hydroxylase promoter

Adverse events in utero, such as intrauterine growth restriction (IUGR), can permanently alter epigenetic mechanisms leading to the metabolic syndrome, which encompasses a variety of symptoms including augmented cholesterol. The major site for cholesterol homeostasis occurs via the actions of hepatic cholesterol 7α-hydroxylase (Cyp7a1), which catabolizes cholesterol to bile acids. To determine whether posttranslational histone modifications influence the long-term expression of Cyp7a1 in IUGR, we used a protein restriction model in rats. This diet during pregnancy and lactation led to IUGR offspring with decreased liver to body weight ratios, followed by increased circulating and hepatic cholesterol levels in both sexes at d 21 and exclusively in the male offspring at d 130. The augmented cholesterol was associated with decreases in the expression of Cyp7a1. Chromatin immunoprecipitation revealed that this was concomitant with diminished acetylation and enhanced methylation of histone H3 lysine 9 [K9,14], markers of chromatin silencing, surrounding the promoter region of Cyp7a1. These epigenetic modifications originate in part due to dietary-induced decreases in fetal hepatic Jmjd2a expression, a histone H3 [K9] demethylase. Collectively, these findings suggest that the augmented cholesterol observed in low-protein diet-derived offspring is due to permanent repressive posttranslational histone modifications at the promoter of Cyp7a1. Moreover, this is the first study to demonstrate that maternal undernutrition leads to long-term cholesterol dysregulation in the offspring via epigenetic mechanisms.

Neither long-term statin use nor atherosclerotic disease is associated with risk of colorectal cancer

BACKGROUND & AIMS

Statin use has been reported to reduce risk for colorectal cancer (CRC) whereas atherosclerotic disease has been reported to increase risk, but findings have been inconsistent. We aimed to establish the association of statin use and coronary atherosclerosis with CRC.

METHODS

We performed a population-based case control study of patients with a first diagnosis of CRC cancer between January 1, 1991, and December 31, 2008 (n = 9979), using the Danish National Registry of Patients. As many as 10 population controls were matched to each patient using risk set sampling (n = 99,790). Statin use before cancer diagnosis (or control index date) was determined via county prescription databases and evidence of coronary atherosclerosis using International Classification of Diseases codes. We calculated incidence rate ratios using conditional logistic regression, adjusted for multiple covariates.

RESULTS

Among patients with CRC, statin use was modest (7.7%), but 23.5% of use was long term (≥5 years). Ever use of statins (≥2 prescriptions) slightly reduced CRC risk, compared with relative to never/rare use (incidence rate ratio [IRR] = 0.87, 95% confidence interval = 0.80-0.96). However, long-term use did not affect risk compared with never/rare use (IRR = 0.95, 95% 0.80-1.12). No associations were observed between atherosclerosis, myocardial infarction, or stroke, and CRC incidence.

CONCLUSIONS

Although there is a weak inverse association between ever use of statins and CRC incidence, there was no trend with increasing duration of use, so statins do not appear to reduce CRC risk. We did not confirm the reported association between atherosclerosis and CRC risk.

Lipid metabolism in myelinating glial cells: lessons from human inherited disorders and mouse models

The integrity of central and peripheral nervous system myelin is affected in numerous lipid metabolism disorders. This vulnerability was so far mostly attributed to the extraordinarily high level of lipid synthesis that is required for the formation of myelin, and to the relative autonomy in lipid synthesis of myelinating glial cells because of blood barriers shielding the nervous system from circulating lipids. Recent insights from analysis of inherited lipid disorders, especially those with prevailing lipid depletion and from mouse models with glia-specific disruption of lipid metabolism, shed new light on this issue. The particular lipid composition of myelin, the transport of lipid-associated myelin proteins, and the necessity for timely assembly of the myelin sheath all contribute to the observed vulnerability of myelin to perturbed lipid metabolism. Furthermore, the uptake of external lipids may also play a role in the formation of myelin membranes. In addition to an improved understanding of basic myelin biology, these data provide a foundation for future therapeutic interventions aiming at preserving glial cell integrity in metabolic disorders.

Atorvastatin-induced cell toxicity in yeast is linked to disruption of protein isoprenylation

Statins, used to treat hypercholesterolemia, are one of the most frequently prescribed drug classes in the developed world. However, a significant proportion of users suffer symptoms of myotoxicity, and currently, the molecular mechanisms underlying myotoxicity remain ambiguous. In this study, Saccharomyces cerevisiae was exploited as a model system to gain further insight into the molecular mechanisms of atorvastatin toxicity. Atorvastatin-treated yeast cells display marked morphological deformities, have reduced cell viability and are highly vulnerable to perturbed mitochondrial function. Supplementation assays of atorvastatin-treated cells reveal that both loss of viability and mitochondrial dysfunction occur as a consequence of perturbation of the sterol synthesis pathway. This was further investigated by supplementing statin-treated cells with various metabolites of the sterol synthesis pathway that are believed to be essential for cell function. Ergosterol, coenzyme Q and a heme precursor were all ineffective in the prevention of statin-induced mitochondrial disruption and cell death. However, the addition of geranylgeranyl pyrophosphate and farnesyl pyrophosphate significantly restored cell viability, although these did not overcome petite induction. This highlights the pleiotropic nature of statin toxicity, but has established protein prenylation disruption as one of the principal mechanisms underlying statin-induced cell death in yeast.

Comparison of pitavastatin with simvastatin in primary hypercholesterolaemia or combined dyslipidaemia

OBJECTIVES

The primary objective of this study was to demonstrate equivalence of pitavastatin compared with simvastatin in the reduction of low-density lipoprotein cholesterol (LDL-C) levels in patients with primary hypercholesterolaemia or combined dyslipidaemia. Secondary objectives included achievement of National Cholesterol Education Program Adult Treatment Panel (NECP) and European Atherosclerosis Society (EAS) LDL-C goals, comparison of other lipid parameters, and assessment of safety and tolerability of the two statins.

RESEARCH DESIGN AND METHODS

A prospective, randomised, active-controlled double-blind, double-dummy, 12-week therapy trial was conducted in 857 patients with either primary hypercholesterolaemia or combined dyslipidaemia. The trial was designed to demonstrate the equivalence (non-inferiority of presumed equipotent doses) of pitavastatin compared with simvastatin. Patients were randomised to one of four groups: pitavastatin 2 mg/day, pitavastatin 4 mg/day, simvastatin 20 mg/day or simvastatin 40 mg/day. The main study limitation was restriction of the study population to those eligible for administration of simvastatin.

TRIAL REGISTRATION

This clinical trial has been registered at www.clinicaltrials.gov NCT# NCT00309777.

RESULTS

Pitavastatin 2 mg showed significantly better reductions of LDL-C (p = 0.014), non-high-density lipoprotein cholesterol (non-HDL-C) (p = 0.021) and total cholesterol (TC) (p = 0.041) compared with simvastatin 20 mg and led to more patients achieving the EAS LDL-C treatment target. Reduction of LDL-C in the pitavastatin 2 mg group was 39% compared with 35% in the simvastatin 20 mg group. Pitavastatin 4 mg showed similar effects on all lipid parameters to simvastatin 40 mg. The reductions in LDL-C were 44% and 43%, respectively. The safety profiles of pitavastatin and simvastatin were similar at the two dose levels. Pitavastatin was considered superior to simvastatin in terms of percent reduction of LDL-C in the lower dose group comparison and proved to be equivalent to simvastatin in percent reduction of LDL-C in the higher-dose group.

CONCLUSION

As compared with simvastatin, an established first-line lipid-lowering agent, pitavastatin is an efficacious treatment choice in patients with primary hypercholesterolaemia or combined dyslipidaemia.

Use of statins in patients with liver disease

Cardiovascular disease is as common in individuals with chronic liver disease as in the general population. Moreover, recent data suggest that patients with nonalcoholic fatty liver disease (NAFLD) may have a cardiovascular risk greater than that conferred by the conventional risk factors. There is unequivocal evidence that cardiovascular disease is an important cause of morbidity and mortality in this patient population and thus requires consideration of aggressive therapy with lipid-lowering agents such as statins. Because all statins are hepatically cleared and can cause elevations in liver biochemistries, there is a concern that patients with underlying liver disease may be at increased risk for hepatotoxicity. However, recent data, along with an assessment of statin safety by the Liver Expert Panel, suggest that statins are generally well tolerated in patients with chronic liver disease such as NAFLD, primary biliary cirrhosis, and hepatitis C virus. These drugs also appear to be safe in patients with stable/compensated cirrhosis. However, decompensated cirrhosis and acute liver failure should be considered contraindications for lipid-lowering therapy as these patients are unlikely to benefit because of their generally grave prognosis. Although routine hepatic biochemical test monitoring is recommended, the cost-effectiveness of this approach has been questioned. The benefit of statins in patients with underlying liver disease who are otherwise important candidates for statin therapy far outweighs the risk of a very rare event of serious liver injury.