Pleiotropic effects of ezetimibe/simvastatin vs. high dose simvastatin

Expanding the therapeutic landscape: ezetimibe as non-statin therapy for dyslipidemia

Dyslipidemia is a significant risk factor for atherosclerotic cardiovascular disease (ASCVD), and statins are the primary therapeutic options for reducing low-density lipoprotein cholesterol (LDL-C) levels. However, it can be challenging to achieve optimal LDL-C goals with statin monotherapy. Ezetimibe, a cholesterol absorption inhibitor, offers a potential non-statin therapy to optimize LDL-C management. Key clinical trials, such as IMPROVE-IT and RACING, have demonstrated that the addition of ezetimibe to statin therapy leads to further decreases in LDL-C or significant decreases in major adverse cardiovascular events (MACEs), particularly in patients with high ASCVD risk. Subsequent meta-analyses and clinical trials have further supported the beneficial effect of ezetimibe, suggesting additive decreases in LDL-C and MACEs, as well as pleiotropic effects. This review provides a comprehensive analysis of the clinical implications of ezetimibe for managing dyslipidemia; it also evaluates the available evidence that supports the role of ezetimibe as an adjunct non-statin therapy for long-term use. However, the long-term pleiotropic effects of ezetimibe remain controversial because of limited clinical data. Therefore, additional research is needed to clarify its potential benefits beyond LDL-C reduction. Nonetheless, an understanding of the role of ezetimibe in dyslipidemia management will help clinicians to develop effective treatment strategies.

Understanding the molecular mechanisms of statin pleiotropic effects

Statins represent the cornerstone of pharmacotherapy for the prevention of atherosclerotic cardiovascular disease. These medications not only reduce low-density lipoprotein cholesterol (LDL-C) via inhibition of 3-hydroxy-3-methylglutarate attached to CoA reductase, the key rate-limiting step in the cholesterol biosynthetic pathway, but also upregulate expression of the low-density lipoprotein receptor, improving serum clearance. Given LDL-C is a causal risk factor for the development of atherosclerosis, these complementary mechanisms largely explain why statin therapy leads to reductions in major adverse cardiovascular events. However, decades of basic and clinical research have suggested that statins may exert other effects independent of LDL-C lowering, termed pleiotropic effects, which have become a topic of debate among the scientific community. While some literature suggests statins may improve plaque stability, reduce inflammation and thrombosis, decrease oxidative stress, and improve endothelial function and vascular tone, other studies have suggested potential harmful pleiotropic effects related to increased risk of muscle-related side effects, diabetes, hemorrhagic stroke, and cognitive decline. Furthermore, the introduction of newer, non-statin LDL-C lowering therapies, including ezetimibe, proprotein convertase subtilisin/Kexin Type 9, and bempedoic acid, have challenged the statin pleiotropy theory. This review aims to provide a historical background on the development of statins, explore the mechanistic underpinnings of statin pleiotropy, review the available literature, and provide up to date examples that suggest statins may exert effects outside of LDL-C lowering and the cardiovascular system.

Prevalence of Cardioprotective Medication Use in Coronary Heart Disease Patients in South America: Systematic review and Meta-Analysis

Background:

Coronary heart disease (CHD) is the most common cause of death globally, and clinical guidelines recommend cardioprotective medications for patients with established CHD. Suboptimal use of these medications has been reported, but information from South America is scarce.

Methods:

We conducted a systematic review on prevalence of secondary prevention medication in South America. We pooled prevalence estimates, analysed time-trends and guideline compliance, and identified factors associated with medication use with meta-regression models.

Results:

73 publications were included. Medication prevalence varied by class: beta-blockers 73.4%(95%CI 66.8%–79.1%), ACEI/ARBs 55.8%(95%CI 49.7%–61.8), antiplatelets 84.6%(95%CI 79.6%–88.5%), aspirin 85.1%(95%CI 79.7%–89.3%) and statins 78.9%(95%CI 71.2%–84.9%). The use of beta-blockers, ACEI/ARBs and statins increased since 1993. Ten publications reported low medication use and nine reported adequate use. Medication use was lower in community, public and rehabilitation settings compared to tertiary centres.

Conclusion:

Cardioprotective medication use has increased, but could be further improved particularly in community settings.

The Effects of Statin Dose, Lipophilicity, and Combination of Statins plus Ezetimibe on Circulating Oxidized Low-Density Lipoprotein Levels: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background

Elevated plasma low-density lipoprotein cholesterol (LDL-C) is the main risk factor for atherosclerotic cardiovascular disease (ASCVD). Statins are the drugs of choice for decreasing LDL-C and are used for the prevention and management of ASCVD. Guidelines recommend that subjects with high and very high ASCVD risk should be treated with high-intensity statins or a combination of high-intensity statins and ezetimibe. The lipophilicity or hydrophilicity (solubility) of statins is considered to be important for at least some of their LDL-C lowering independent pleiotropic effects. Oxidative modification of LDL (ox-LDL) is considered to be the most important atherogenic modification of LDL and is supposed to play a crucial role in atherogenesis and ASCVD outcomes.

Objective

The aim of this systematic review and meta-analysis was to find out what are the effects of statin intensity, lipophilicity, and combination of statins plus ezetimibe on ox-LDL.

Methods

PubMed, Scopus, Embase, and Web of Science were searched from inception to February 5, 2021, for randomized controlled trials (RCTs). Two independent and blinded authors evaluated eligibility by screening the titles and abstracts of the studies. Risk of bias in the studies included in this meta-analysis was evaluated according to the Cochrane instructions. Meta-analysis was performed using Comprehensive Meta-Analysis (CMA) V2 software. Evaluation of funnel plot, Begg's rank correlation, and Egger's weighted regression tests were used to assess the presence of publication bias.

Results

Among the 1427 published studies identified by a systematic databases search, 20 RCTs were finally included in the systematic review and meta-analysis. A total of 1874 patients are included in this meta-analysis. This meta-analysis suggests that high-intensity statin treatment is associated with a significant decrease in circulating concentrations of ox-LDL when compared with low-to-moderate treatment (SMD: -0.675, 95% CI: -0.994, -0.357, p < 0.001; I²: 55.93%). There was no difference concerning ox-LDL concentration between treatments with hydrophilic and lipophilic statins (SMD: -0.129, 95% CI: -0.330, -0.071, p = 0.206; I²: 45.3%), but there was a significant reduction in circulating concentrations of ox-LDL associated with statin plus ezetimibe combination therapy when compared with statin monotherapy (SMD: -0.220, 95% CI: -0.369, -0.071, p = 0.004; I²: 0%).

Conclusion

High-dose statin or combination of statins with ezetmibe reduces plasma ox-LDL in comparison low-to-moderate intensity statin therapy alone. Statin lipophilicity is not associated with reduction in ox-LDL plasma concentrations.

Similar major cardiovascular outcomes between pure statin and ezetimibe-statin in comparable intensity for type 2 diabetes with extremely atherosclerotic risks

Atorvastatin 40 mg (ATOR 40) and ezetimibe 10 mg/simvastatin 20 mg (EZ-SIM 20) have similar reductions of low-density lipoprotein cholesterol (LDL-C) but cardiovascular (CV) outcomes between these two therapies are unclear. Our real-world cohort study is to test the hypothesis of pleiotropic effects of purely higher dose statin on CV outcomes beyond similar reductions of LDL-C, especially for extremely CV risk patients. Between January 1, 2007 and December 31, 2013, a total of 3,372 patients with type 2 diabetes mellitus (T2DM) admitted due to acute coronary syndrome (ACS) or acute ischemic stroke (AIS) were selected as the study cohort from the Taiwan National Health Insurance Research Database. Clinical outcomes were evaluated by ATOR 40 group (n = 1686) matched with EZ-SIM 20 group (n = 1686). Primary composite outcome includes CV death, non-fatal myocardial infarction, and non-fatal stroke. Secondary composite outcome includes hospitalization for unstable angina (HUA), percutaneous coronary intervention (PCI), and coronary artery bypass grafting (CABG). With a mean follow-up of 2.4 years, no significant difference of primary composite outcome was observed between ATOR 40 and EZ-SIM 20 groups (subdistribution hazard ratio [SHR], 1.09; 95% confidence interval [CI], 0.95–1.25). Nevertheless, ATOR 40 group had lower risks of HUA (SHR, 0.50; 95% CI, 0.35–0.72), PCI (SHR, 0.82; 95% CI, 0.69–0.97) and CABG (SHR, 0.62; 95% CI, 0.40–0.97) than EZ-SIM 20 group. For T2DM patients after ACS or AIS, ATOR 40 and EZ-SIM 20 had similar major CV outcomes, which still supported the main driver for CV risk reductions is LDL-C lowering.

Efficacy and safety of add on therapies in patients with hypercholesterolemia undergoing statin therapy

INTRODUCTION

Statins are the first-line treatment to reduce cardiovascular (CV) events, mainly by reducing low-density-lipoprotein cholesterol (LDL-C), but many patients need additional treatments to reach the current lipid goals.

AREAS COVERED

Herein, the authors review the published literature on the efficacy and safety of the therapies that are most often added to statins to achieve lipid targets.

EXPERT OPINION

Ezetimibe is usually the first additional treatment to achieve LDL-C targets. It reduces LDL-C by about a further 20% and has an excellent safety and tolerability profile. The monoclonal antibody proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, evolocumab, and alirocumab, can reduce LDL-C by ≥50% when added to statins and they also have a well-established safety and tolerability record. The recently approved bempedoic acid is well tolerated and appears to be free of skeletal muscle-related problems, but the CV outcome study with this drug has not been completed. Inclisiran, a small-interfering RNA targeting PCSK9 is at an advanced stage of development and the available data indicate a satisfactory safety profile and LDL-C lowering efficacy similar to the PCSK9 monoclonal antibodies with the advantage of less frequent administration.

Lipoproteins and lipids in cardiovascular disease: from mechanistic insights to therapeutic targeting

With cardiovascular disease being the leading cause of morbidity and mortality worldwide, effective and cost-efficient therapies to reduce cardiovascular risk are highly needed. Lipids and lipoprotein particles crucially contribute to atherosclerosis as underlying pathology of cardiovascular disease and influence inflammatory processes as well as function of leukocytes, vascular and cardiac cells, thereby impacting on vessels and heart. Statins form the first-line therapy with the aim to block cholesterol synthesis, but additional lipid-lowering drugs are sometimes needed to achieve low-density lipoprotein (LDL) cholesterol target values. Furthermore, beyond LDL cholesterol, also other lipid mediators contribute to cardiovascular risk. This review comprehensively discusses low- and high-density lipoprotein cholesterol, lipoprotein (a), triglycerides as well as fatty acids and derivatives in the context of cardiovascular disease, providing mechanistic insights into their role in pathological processes impacting on cardiovascular disease. Also, an overview of applied as well as emerging therapeutic strategies to reduce lipid-induced cardiovascular burden is provided.

The Pleiotropic Effects of Statins - From Coronary Artery Disease and Stroke to Atrial Fibrillation and Ventricular Tachyarrhythmia

Statins, 3-hydroxy-methylglutaryl coenzyme A reductase inhibitors, have been used for decades for the prevention of coronary artery disease and stroke. They act primarily by lowering serum cholesterol through the inhibition of cholesterol synthesis in the liver, which results in the upregulation of low-density lipoprotein receptors in the liver. This results in the removal of low-density lipoproteincholesterol. Studies have suggested that statins may demonstrate additional effects that are independent of their effects on low-density lipoprotein-cholesterol. These have been termed "pleiotropic" effects. Pleiotropic effects may be due to the inhibition of isoprenoid intermediates by statins. Isoprenoid inhibition has effects on the small guanosine triphosphate binding proteins Rac and Rho which in turn effects nicotinamide adenine dinucleotide phosphate oxidases. Therefore, there are changes in endothelial nitric oxide synthase expression, atherosclerotic plaque stability, pro-inflammatory cytokines and reactive oxygen species production, platelet reactivity, and cardiac fibrosis and hypetrophy development. Recently, statins have been compared to the ezetimibe and the recently published outcomes data on the proprotein convertase subtilisin kexin type 9 inhibitors has allowed for a reexamination of statin pleiotropy. As a result of these diverse effects, it has been suggested that statins also have anti-arrhythmic effects. This review focuses on the mechanisms of statin pleiotropy and discusses evidence from the statin clinical trials as well as examining the possible anti-arrhythmic effects atrial fibrillation and ventricular tachyarrhythmias.

Stroke Prevention With the PCSK9 (Proprotein Convertase Subtilisin-Kexin Type 9) Inhibitor Evolocumab Added to Statin in High-Risk Patients With Stable Atherosclerosis

Background and Purpose—

The PCSK9 (proprotein convertase subtilisin-kexin type 9) monoclonal antibody evolocumab lowered LDL (low-density lipoprotein) cholesterol by 59% to 0.8 (0.5–1.2) mmol/L and significantly reduced major vascular events in the FOURIER trial (Further Cardiovascular Outcomes Research with PCSK9 Inhibition in Subjects with Elevated Risk). Herein, we report the results of a prespecified analysis of cerebrovascular events in the overall trial population and in patients stratified by prior stroke.

Methods—

FOURIER was a randomized, double-blind trial comparing evolocumab versus placebo in patients with established atherosclerosis, additional risk factors, and LDL cholesterol levels ≥1.8 (or non-HDL [high-density lipoprotein] ≥2.6 mmol/L) on statin therapy. The median follow-up was 2.2 years. We analyzed the efficacy of evolocumab to reduce overall stroke and stroke subtypes, as well as the primary cardiovascular composite end point by subgroups according to a history of stroke.

Results—

Among the 27 564 patients, 469 (1.7%) experienced a total of 503 strokes of which 421 (84%) were ischemic. Prior ischemic stroke, diabetes mellitus, elevated CRP (C-reactive protein), history of heart failure, older age, nonwhite race, peripheral arterial disease, and renal insufficiency were independent predictors of stroke. Evolocumab significantly reduced all stroke (1.5% versus 1.9%; hazard ratio, 0.79 [95% CI, 0.66–0.95]; P =0.01) and ischemic stroke (1.2% versus 1.6%; hazard ratio, 0.75 [95% CI, 0.62–0.92]; P =0.005), with no difference in hemorrhagic stroke (0.21% versus 0.18%; hazard ratio, 1.16 [95% CI, 0.68–1.98]; P =0.59). These findings were consistent across subgroups, including among the 5337 patients (19%) with prior ischemic stroke in whom the hazard ratios (95% CIs) were 0.85 (0.72–1.00) for the cardiovascular composite, 0.90 (0.68–1.19) for all stroke, and 0.92 (0.68–1.25) for ischemic stroke ( P interactions, 0.91, 0.22, and 0.09, respectively, compared with patients without a prior ischemic stroke).

Conclusions—

Inhibition of PCSK9 with evolocumab added to statin in patients with established atherosclerosis reduced ischemic stroke and cardiovascular events in the total population and in key subgroups, including those with prior ischemic stroke.

Registration—

URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01764633.

Significant effect of simvastatin and/or ezetimibe-loaded nanofibers on the healing of femoral defect: An experimental study

BACKGROUND

Fracture healing complications are associated with significant healthcare and economic burden. In this study, we aimed to investigate how the combined administration of local simvastatin and ezetimibe into the femoral defect of the animal model affects the bone-healing process in comparison with their monotherapy.

METHODS

A total of 32 four-month-old adult male Wistar rats were randomized into the four study groups: simvastatin + ezetimibe-loaded nanofibers (group 1), simvastatin-loaded nanofibers (group 2), ezetimibe-loaded nanofibers (group 3), and non-loaded nanofibers (group 4). After the generation of femoral defects, the predesigned nanofibers were locally administered into the defect site. The healing measures were serum and bone osteoprotegerin (OPG) expression, pathologic evaluation of union (Allen's fracture healing scores), and radiographic evaluation of bone density (Hounsfield scale) at weeks 2 and 4.

RESULTS

The improvement of all evaluated healing measures was remarkably superior in rats that were treated with loaded nanofibers in comparison with the control group. Also, the improvement of all evaluated healing measures was considerably more in the simvastatin-ezetimibe combination therapy group compared to their monotherapy. All the evaluated measures were superior in the ezetimibe monotherapy group compared to the simvastatin monotherapy group.

CONCLUSION

The cumulative effect of simvastatin and ezetimibe on the induction of bone healing is more significant than the individual effect of these drugs. Therefore, local administration of nanofibers loaded with simvastatin and ezetimibe could be regarded as a promising osteoinductive compound for the acceleration of bone repair.

Association of Serum Cholesterol Levels With Peripheral Nerve Damage in Patients With Type 2 Diabetes

IMPORTANCE

Lowering serum cholesterol levels is a well-established treatment for dyslipidemia in patients with type 2 diabetes (T2D). However, nerve lesions in patients with T2D increase with lower serum cholesterol levels, suggesting that lowering serum cholesterol levels is associated with diabetic polyneuropathy (DPN) in patients with T2D.

OBJECTIVE

To investigate whether there is an association between serum cholesterol levels and peripheral nerve lesions in patients with T2D with and without DPN.

DESIGN, SETTING, AND PARTICIPANTS

This single-center, cross-sectional, prospective cohort study was performed from June 1, 2015, to March 31, 2018. Observers were blinded to clinical data. A total of 256 participants were approached, of whom 156 were excluded. A total of 100 participants consented to undergo magnetic resonance neurography of the right leg at the Department of Neuroradiology and clinical, serologic, and electrophysiologic assessment at the Department of Endocrinology, Heidelberg University Hospital, Heidelberg, Germany.

EXPOSURES

Quantification of the nerve's diameter and lipid equivalent lesion (LEL) load with a subsequent analysis of all acquired clinical and serologic data with use of 3.0-T magnetic resonance neurography of the right leg with 3-dimensional reconstruction of the sciatic nerve.

MAIN OUTCOMES AND MEASURES

The primary outcome was lesion load and extension. Secondary outcomes were clinical, serologic, and electrophysiologic findings.

RESULTS

A total of 100 participants with T2D (mean [SD] age, 64.6 [0.9] years; 68 [68.0%] male) participated in the study. The LEL load correlated positively with the nerve's mean cross-sectional area (r = 0.44; P < .001) and the maximum length of a lesion (r = 0.71; P < .001). The LEL load was negatively associated with total serum cholesterol level (r = -0.41; P < .001), high-density lipoprotein cholesterol level (r = -0.30; P = .006), low-density lipoprotein cholesterol level (r = -0.33; P = .003), nerve conduction velocities of the tibial (r = -0.33; P = .01) and peroneal (r = -0.51; P < .001) nerves, and nerve conduction amplitudes of the tibial (r = -0.31; P = .02) and peroneal (r = -0.28; P = .03) nerves.

CONCLUSIONS AND RELEVANCE

The findings suggest that lowering serum cholesterol levels in patients with T2D and DPN is associated with a higher amount of nerve lesions and declining nerve conduction velocities and amplitudes. These findings may be relevant to emerging therapies that promote an aggressive lowering of serum cholesterol levels in patients with T2D.

Using co-axial electrospray deposition to eliminate burst release of simvastatin from microparticles and to enhance induced osteogenesis

Microparticles (MPs) exhibit fast dissolution, characterized by a burst drug release pattern. In the present work, we prepared core-shell MPs of simvastatin (SIM) and zein with chitosan (CS) and nano-hydroxyapatite (nHA) as a drug carrier using the coaxial electrospray deposition method. The morphology, formation and in vitro osteogenic differentiation of these MPs were studied. The synthetic MPs have a diameter of about 1 μm and they are composed of non-toxic natural materials. They provide an effective way to enable long-term sustained-release activity, which is controlled by their double layer structures. The CS-nHA/zein-SIM MPs presented a low initial burst release (approximately 35-47%) within the first 24 h of application followed by the sustained release for at least 4 weeks. In vitro cell culture experiments were performed and the results revealed that the CS-nHA/zein-SIM core-shell MPs were beneficial to the adhesion, proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). The CS-nHA/zein-SIM MPs with a low SIM concentration were beneficial to cell proliferation and promotion of osteogenic differentiation.

Comparison of statin plus ezetimibe with double-dose statin on lipid profiles and inflammation markers

Background

Achievement of low-density lipoprotein cholesterol (LDL-C) goal is the most important for the patients with atherosclerotic cardiovascular diseases (ASCVD) who received lipid-lowering therapy. It is unclear that whether combination of ezetimibe with statin is superior to double-dose of statin regarding both of the lipid-lowering efficacy and improvement of inflammation in Chinese patients with ASCVD. Therefore, this study was performed to compare the effects of these two regimes on lipid profiles and inflammation markers.

Methods

In this randomized control study, ninety eight patients with ASCVD, who were naïve to statins or other lipid-lowering agents, were enrolled into the study, and randomly assigned into two groups, A40 group (atorvastatin 40 mg/d, n = 50), A20E10 group (atorvastatin 20 mg/d combined with ezetimibe 10 mg/d, n = 48).The patients were followed up at week 4 and week 12 after treatment. The lipid profiles and oxidative low-density lipoprotein cholesterol (ox-LDL) were measured at the end of study.

Results

There were no differences in clinical characteristics including lipid, ox-LDL and hypersensitive C reactive protein (Hs-CRP) among groups at baseline. However, the average level of LDL-C was lower in group A20E10 than that in group A40 significantly (1.59 ± 0.44 mmol/L vs 1.99 ± 0.56 mmol/L, p = 0.001) during follow-up at week 12 after treatment. Importantly, the higher rate of achievement of LDL-C goal was attained at group of combination statin with ezetimibe (79.2% in group A20E10 vs 50.0% in group A40, p = 0.016). The difference of the level of ox-LDL between both the groups after 12 weeks treatment had not statistical significance (3.63 ± 1.13 U/L in group A20E10 vs 4.14 ± 1.32 U/L in group A40, p = 0.077).Similarly, the level of Hs-CRP between both the groups after treatment was not significantly different (p > 0.05).

Conclusions

In this randomized study, the data showed that a combination of moderate statin and ezetimibe achieved more reduction of LDL-C compared to the double-dose statin but similar impact on inflammation markers.

Ezetimibe in high-risk, previously treated statin patients: a systematic review and network meta-analysis of lipid efficacy

PURPOSE

While statins are used as first-line treatments for high-risk patients with hypercholesterolemia, statin monotherapy is often insufficient to achieve target low-density lipoprotein cholesterol (LDL-C) levels. Second-line treatment options include up-titration of statin dose, switching to a more potent statin, or combination therapy, e.g., with ezetimibe. The aim of this study was to evaluate the efficacy of adding ezetimibe to simvastatin, atorvastatin, or rosuvastatin monotherapy versus doubling the dosage or switching to a higher-potency statin in a population of patients with hypocholesterolemia at high risk of cardiovascular disease (CVD) and who had been previously treated with a statin.

METHODS

A systematic literature search was performed and evidence bases were established for populations of atorvastatin-, simvastatin-, and rosuvastatin-experienced patients using eligible randomized controlled trials (RCTs). Based on the available data, we constructed networks of evidence and conducted a Bayesian network meta-analysis (NMA) within each statin population. The primary outcome of interest was percent change from baseline in LDL-C. Changes in total cholesterol were explored as a secondary outcome.

FINDINGS

Across all patient populations, 35 RCTs were identified and included in the evidence base. Among patients on simvastatin therapy, the addition of ezetimibe resulted in a mean difference (MD) in LDL-C of - 13.62% (95% CrI - 19.99, - 6.91; see table below) compared to doubling the starting dose of simvastatin. In the population of patients on atorvastatin therapy, the addition of ezetimibe resulted in an MD in LDL-C of - 14.71% (95% CrI - 16.46, - 12.95) compared to doubling the starting dose of atorvastatin. The addition of ezetimibe to rosuvastatin resulted in an MD in LDL-C of - 14.96% (95% CrI - 17.79, - 12.11), compared to doubling the starting rosuvastatin dose. Similar trends were observed for changes in total cholesterol.

IMPLICATIONS

Given the available data, the addition of ezetimibe to ongoing simvastatin, atorvastatin, or rosuvastatin monotherapy offers greater reduction in LDL-C among patients at high risk of CVD compared to doubling the initial statin dose.

Pleiotropic Effects of Statins on the Cardiovascular System

The statins have been used for 30 years to prevent coronary artery disease and stroke. Their primary mechanism of action is the lowering of serum cholesterol through inhibiting hepatic cholesterol biosynthesis thereby upregulating the hepatic low-density lipoprotein (LDL) receptors and increasing the clearance of LDL-cholesterol. Statins may exert cardiovascular protective effects that are independent of LDL-cholesterol lowering called pleiotropic effects. Because statins inhibit the production of isoprenoid intermediates in the cholesterol biosynthetic pathway, the post-translational prenylation of small GTP-binding proteins such as Rho and Rac, and their downstream effectors such as Rho kinase and nicotinamide adenine dinucleotide phosphate oxidases are also inhibited. In cell culture and animal studies, these effects alter the expression of endothelial nitric oxide synthase, the stability of atherosclerotic plaques, the production of proinflammatory cytokines and reactive oxygen species, the reactivity of platelets, and the development of cardiac hypertrophy and fibrosis. The relative contributions of statin pleiotropy to clinical outcomes, however, remain a matter of debate and are hard to quantify because the degree of isoprenoid inhibition by statins correlates to some extent with the amount of LDL-cholesterol reduction. This review examines some of the currently proposed molecular mechanisms for statin pleiotropy and discusses whether they could have any clinical relevance in cardiovascular disease.

Therapeutic Targeting of Cellular Stress to Prevent Cardiovascular Disease: A Review of the Evidence

The availability of effective drugs targeting the major risk factors of cardiovascular disease (CVD) has reduced morbidity and mortality. Cumulative relative risk of CVD events can be reduced by 75 % with a combination of aspirin, a β-adrenoceptor antagonist (β-blocker), an HMG-CoA reductase inhibitor (statin), and an angiotensin-converting enzyme inhibitor. The principal pharmacodynamics of these drugs cannot explain the entirety of their cardioprotective action, as other drugs with similar pharmacologic targets have not been associated with favorable clinical effects. This raises the possibility that the cardioprotective drugs have a unique pleiotropic activity that contributes to their clinical efficacy. Recent data suggest that reducing cellular stress such as oxidative, inflammatory, and endoplasmic reticulum stress, might be a common denominator of the drugs with proven efficacy in reducing CVD risk. In this communication, the evidence in favor of this hypothesis is discussed, and ongoing trials with therapeutic agents targeting cellular stresses are reviewed.

Diabetic Polyneuropathy in Type 2 Diabetes Mellitus: Inflammation, Oxidative Stress, and Mitochondrial Function

Diabetic polyneuropathy (DPN) is defined as peripheral nerve dysfunction. There are three main alterations involved in the pathologic changes of DPN: inflammation, oxidative stress, and mitochondrial dysfunction. Inflammation induces activation of nuclear factor kappa B, activator protein 1, and mitogen-activated protein kinases. Oxidative stress induced by hyperglycemia is mediated by several identified pathways: polyol, hexosamine, protein kinase C, advanced glycosylation end-products, and glycolysis. In addition, mitochondrial dysfunction accounts for most of the production of reactive oxygen and nitrosative species. These free radicals cause lipid peroxidation, protein modification, and nucleic acid damage, to finally induce axonal degeneration and segmental demyelination. The prevalence of DPN ranges from 2.4% to 78.8% worldwide, depending on the diagnostic method and the population assessed (hospital-based or outpatients). Risk factors include age, male gender, duration of diabetes, uncontrolled glycaemia, height, overweight and obesity, and insulin treatment. Several diagnostic methods have been developed, and composite scores combined with nerve conduction studies are the most reliable to identify early DPN. Treatment should be directed to improve etiologic factors besides reducing symptoms; several approaches have been evaluated to reduce neuropathic impairments and improve nerve conduction, such as oral antidiabetics, statins, and antioxidants (alpha-lipoic acid, ubiquinone, and flavonoids).

Preprocedural statin therapy, inflammation, and myocardial injury in low-risk stable coronary artery disease patients submitted to coronary stent implantation

OBJECTIVE

Evaluate if statin therapy prior to elective coronary stent implantation (CSI) reduces the plasma levels of markers of inflammation and of myocardial necrosis in low-risk stable coronary artery disease patients (CAD).

BACKGROUND

The elevation of markers of inflammation and of myocardial necrosis after percutaneous coronary intervention may interfere with clinical outcome. Among acute coronary syndrome patients, statins improve clinical outcomes when used before CSI-mostly due to reduction of CSI-related myocardial infarction. However, little is known concerning preprocedural statin therapy on the reduction of these markers in stable patients at low-risk.

METHODS

In this prospective, observational study, 100 patients (n = 50 on statin therapy vs. n = 50 not on statin) with stable coronary artery disease underwent elective CSI. Inflammatory (C-reactive protein [CRP], interleukin [IL]-6, tumor necrosis factor-α and matrix metalloproteinase-9) and myocardial necrosis markers (troponin I and CK-MB) were determined before and 24 hr after CSI.

RESULTS

All patients presented a significant increase of CRP and IL-6 after CSI. However, this increase was attenuated in patients on statin therapy prior to CSI than those without statin therapy: 75% vs. 150% (P < 0.001) and 192% vs. 300% (P < 0.01). The other pro-inflammatory markers were similar for both sets of patients. Troponin I and CK-MB did not change after CSI regardless of previous statin therapy or not.

CONCLUSIONS

Pretreatment with statin attenuates procedural inflammation, denoted by markedly lower increases of CRP and IL-6 levels, in elective CSI within low-risk stable CAD patients. Periprocedural myocardial injury was irrelevant and was not affected by preprocedural statin therapy in this population.

Impact of combination therapy with statin and ezetimibe on secondary prevention for post-acute myocardial infarction patients in the statin era

BACKGROUND

Little is known concerning the effect of ezetimibe for secondary prevention in post-myocardial infarction (MI) patients. In this study, we investigated the secondary prevention effect of ezetimibe for post-MI patients.

METHODS

This study is a retrospective analysis of Assessing Lipophilic vs. hydrophilic Statin therapy for Acute MI (ALPS-AMI study). The patients were divided into two groups: those administered a statin to control low density lipoprotein-cholesterol (LDL-C), the ezetimibe(-) group, and those administered ezetimibe in addition to a statin to control LDL-C, the ezetimibe(+) group. The endpoints were Major Adverse Cardiac and Cerebrovascular Event (MACCE), including all-cause death, recurrence of MI, stroke, and heart failure requiring hospitalization, and MACCE with revascularization.

RESULTS

The ezetimibe(+) and ezetimibe(-) groups contained 113 and 337 patients, respectively. Incidences of MACCE and MACCE with revascularization were lower in the ezetimibe(+) group than in the ezetimibe(-) group (2.6% vs. 11.5%, p = 0.002; 23.0% vs. 36.7%, p = 0.014, respectively). Moreover, logistic regression analysis revealed ezetimibe(+) was a significant negative predictor of MACCE (OR 0.208, 95% CI 0.048 to 0.903, p = 0.047) and MACCE with revascularization (OR 0.463, 95% CI 0.258 to 0.831, p = 0.008). The preventive effect of ezetimibe against MACCE was observed in both moderate- and high-intensity lipid lowering treatment groups (0% vs. 17%; p = 0.077, 3.1% vs. 9.4%; p = 0.033).

CONCLUSIONS

In lipid-lowering therapy post-MI, ezetimibe and statin combination therapy improved MACCE with or without revascularization compared with statin monotherapy. These findings suggest that post-MI secondary prevention should be more intensive.

Persistent lipid abnormalities in statin-treated coronary artery disease patients with and without diabetes in China

BACKGROUND

We evaluate the prevalence of persistent lipid abnormalities and statin use in Chinese coronary artery disease patients with and without diabetes.

METHODS AND RESULTS

In this cross-sectional observational study, 8965 outpatients from 200 clinical departments of 122 hospitals in 27 provinces nationwide of China who had coronary artery disease and were taking a statin were consecutively enrolled and divided into two groups based on diabetes status. The European Society of Cardiology/European Arthrosclerosis Society Guidelines for the management of dyslipidemias and the Chinese Guidelines on Prevention and Treatment of Dyslipidemia in Adults were used to compare the control rates of low density lipoprotein (LDL) cholesterol, high density lipoprotein (HDL) cholesterol, and triglycerides (TG). Among the 8965 participants, 33.3% had been diagnosed with diabetes mellitus. According to the ESC Guidelines, the percentage of patients with not at goal LDL cholesterol did not differ significantly between patients with diabetes and those without diabetes (71.9% vs. 72.7%, P=0.46). The percentages of patients with not-at-goal levels of HDL and TG were 42.9% vs. 34.4% (P<0.001) and 39.1% vs. 34.3% (P<0.001) among patients with diabetes and those without, respectively. Only approximately 10% of patients in both groups had optimal LDL-C, HDL-C, and TG levels. Compared with patients without diabetes, patients with diabetes were more likely to have mixed dyslipidemia. Atorvastatin (47.0%) and simvastatin (34.4%) were the two most frequently used statins, and the average statin dosage was 29.09mg/day (simvastatin equivalent). Less than 1% of patients were treated with another lipid-lowering drug in combination with a statin.

CONCLUSIONS

Although international guidelines highly recommend intensive lipid modulation in patients with coronary artery disease, persistent dyslipidemia is still prevalent among these patients in China, even with statin treatment.

Vascular calcification: pathophysiology and clinical implications

Vascular calcification in coronary artery disease is gaining importance, both in scientific research and in clinical and imaging applications. The calcified plaque is considered the most relevant form of atherosclerosis within the coronary artery tree and is frequently a challenge for percutaneous intervention. Recent studies showed that plaque calcification is dynamic and is strictly related to the degree of vascular inflammation. Several inflammatory factors produced during the different phases of atherosclerosis induce the expression and activation of osteoblastic cells located within the arterial wall, which, in turn, promote the deposit of calcium. The vascular smooth muscle cells have an extraordinary capacity to undergo osteoblastic phenotypical differentiation. There is no doubt that the role of these factors, as well as the elements of genomics and proteomics, could be a vital strategic point in prevention and treatment. Within this context, we conducted an updating review on coronary calcification focused on pathophysiology, experimental models, and clinical implications of vascular calcification.

Increasing doses of simvastatin versus combined ezetimibe/simvastatin: effect on circulating endothelial progenitor cells

BACKGROUND

Patients with coronary artery disease (CAD) should be treated with statins to attain very low cholesterol levels, in order to reduce cardiovascular adverse events. More than 70% of these patients do not reach the appropriate cholesterol goal despite moderate statin doses. However, it is not known whether therapeutic uptitration with different lipid-lowering strategies has a similar "pleiotropic" effect on atherosclerotic endothelial dysfunction evaluated by measurement of endothelial progenitor cells (EPCs).

OBJECTIVE

We sought to compare, in patients with stable CAD and with a low-density lipoprotein cholesterol (LDL-C) >70 mg/dL on treatment with simvastatin 20 mg, the effects on EPCs by increasing simvastatin to 80 mg versus adding ezetimibe 10 mg.

METHODS

Patients (n = 68, 63 ± 9 years, 39% men) were randomly allocated to receive ezetimibe 10/simvastatin 20 mg or simvastatin 80 mg for 6 weeks. Circulating EPCs were measured by flow cytometry before and after the treatment.

RESULTS

Both strategies presented similar effects on metabolic parameters. The LDLs were equally reduced by ezetimibe 10/simvastatin 20 mg and simvastatin 80 mg (28.9% ± 13% vs 21.1% ± 33%; P = .46, respectively). The levels of EPCs were unaffected by ezetimibe 10/simvastatin 20 mg (median [25th, 75th]: pre- vs posttreatment, 7.0 [2.3; 13.3] vs 3.1 [0.1; 13.2] EPCs/10(4) mononuclear cells; P = .43) or simvastatin 80 mg (pre- vs posttreatment, 6.1 [2.9; 15.2] vs 4.0 [1.4; 10.7] EPCs/10(4) mononuclear cells; P = .5), and there were no differences between the groups on treatment effects (P = .9).

CONCLUSIONS

Among stable patients with CAD and with an LDL-C >70 mg/dL on simvastatin 20 mg, increasing simvastatin dose to 80 mg or adding ezetimibe 10 mg promoted similar further cholesterol reduction but did not have incremental effects on circulating EPCs. These data suggest that the effects of simvastatin moderate doses on EPCs are not increased by intensive lipid-lowering strategies (clinicaltrials.gov: NCT00474123).

Comparison of anti-inflammatory effects and high-density lipoprotein cholesterol levels between therapy with quadruple-dose rosuvastatin and rosuvastatin combined with ezetimibe

BACKGROUND

Statins are frequently administered to reduce low-density lipoprotein cholesterol (LDL-C) and vascular inflammation, because LDL-C and high sensitive C-reactive protein (hs-CRP) are associated with high risk for cardiovascular events. When statins do not reduce LDL-C to desired levels in high-risk patients with coronary artery disease (CAD), ezetimibe can be added or the statin dose can be increased. However, which strategy is more effective for treating patients with CAD has not been established. The present study compares anti-inflammatory effects and lipid profiles in patients with CAD and similar LDL-C levels who were treated by increasing the statin dose or by adding ezetimibe to the original rosuvastatin dose to determine the optimal treatment for such patients.

METHODS

46 patients with high-risk CAD and LDL-C and hs-CRP levels of >70 mg/dL and >1.0 mg/L, respectively, that were not improved by 4 weeks of rosuvastatin (2.5 mg/day) were randomly assigned to receive 10 mg (R10, n = 24) of rosuvastatin or 2.5 mg/day of rosuvastatin combined with 10 mg/day of ezetimibe (R2.5/E10, n = 22) for 12 weeks. The primary endpoint was a change in hs-CRP.

RESULTS

Baseline characteristics did not significantly differ between the groups. At 12 weeks, LDL-C and inflammatory markers (hs-CRP, interleukin-6, tumour necrosis factor-alpha and pentraxin 3) also did not significantly differ between the two groups (LDL-C: R10 vs. R2.5/E10: -19.4 ± 14.2 vs. -22.4 ± 14.3 mg/dL). However, high-density lipoprotein cholesterol (HDL-C) was significantly improved in the R10, compared with R2.5/E10 group (4.6 ± 5.9 vs. 0.0 ± 6.7 mg/dL; p < 0.05).

CONCLUSION

Both enhanced therapies exerted similar anti-inflammatory effects under an equal LDL-C reduction in patients with high-risk CAD despite 2.5 mg/day of rosuvastatin. However, R10 elevated HDL-C more effectively than R2.5/E10.

TRIAL REGISTRATION

UMIN000003746.