Statins and Blood Coagulation

Short-term high-dose effect of lovastatin on thrombolysis by rt-PA in a human whole-blood in vitro clot model

High-dose hydroxymethylglutaryl coenzyme. A reductase inhibitor (statin) administration reduces neuronal injury and improves outcomes in experimental models of acute ischemic stroke, and has been shown to be safe in a phase 1 dose-escalation study using lovastatin at doses higher than currently approved for daily use. Statins also affect the hemostatic system by upregulating t-PA expression and decreasing plasminogen activator inhibitor (PAI-1) expression, platelet adhesion and thrombus formation in animal models. Since a thrombolytic agent, recombinant tissue plasminogen activator (rt-PA), is currently the only FDA-approved therapy for use in ischemic stroke patients, it is important to ascertain whether high statin doses impact the efficacy of rt-PA. The main goal of this study was to evaluate the effect of a high dose of lovastatin and its active form, lovastatin hydroxy acid, on rt-PA thrombolysis in an in vitro model. Percentage clot lysis was measured in the presence and absence of rt-PA in three different treatment groups: lovastatin, lovastatin hydroxy acid, and ethanol. The effect of ethanol on clot lysis was studied since ethanol was used to disperse the highly hydrophobic lovastatin. The decrease in clot width over time was measured using microscopic imaging of an in vitro human whole blood clot model; an approximately 400 μm diameter clot was formed on suture silk, suspended in human fresh frozen plasma (hFFP) and exposed to treatment. In the absence of rt-PA, clot lysis did not show statistically significant differences in the percentage clot lysis between different treatment groups (p=0.103). In the presence of rt-PA, clot lysis was greater than in the absence of rt-PA for all groups, but there were no statistically significant differences between treatment groups (p=0.385). In this in vitro study, high doses of lovastatin neither impaired nor enhanced the lytic efficacy of rt-PA.

Pravastatin-induced proangiogenic effects depend upon extracellular FGF-2

The HMG-CoA reductase inhibitors (statins) have been shown to exert several protective effects on the vasculature that are unrelated to changes in the cholesterol profile, and to induce angiogenesis. The proangiogenic effect exerted by statins has been attributed to the activation of the PI3K/Akt pathway in endothelial cells; however, it is unclear how statins activate this pathway. Pravastatin-mediated activation of Akt and MAPK occurs rapidly (within 10 min.) and at low doses (10 nM). Here, we hypothesized that FGF-2 contributes to the proangiogenic effect of statins. We found that pravastatin, a hydrophilic statin, induced phosphorylation of the FGF receptor (FGFR) in human umbilical vein endothelial cells. SU5402, an inhibitor of FGFR, abolished pravastatin-induced PI3K/Akt and MAPK activity. Likewise, anti-FGF-2 function-blocking antibodies inhibited Akt and MAPK activity. Moreover, depletion of extracellular FGF-2 by heparin prevented pravastatin-induced phosphorylation of Akt and MAPK. Treatment with FGF-2 antibody inhibited pravastatin-enhanced endothelial cell proliferation, migration and tube formation. These observations indicate that pravastatin exerts proangiogenic effects in endothelial cells depending upon the extracellular FGF-2.

Effect of statins on venous thromboembolic events: a meta-analysis of published and unpublished evidence from randomised controlled trials

BACKGROUND

It has been suggested that statins substantially reduce the risk of venous thromboembolic events. We sought to test this hypothesis by performing a meta-analysis of both published and unpublished results from randomised trials of statins.

METHODS AND FINDINGS

We searched MEDLINE, EMBASE, and Cochrane CENTRAL up to March 2012 for randomised controlled trials comparing statin with no statin, or comparing high dose versus standard dose statin, with 100 or more randomised participants and at least 6 months' follow-up. Investigators were contacted for unpublished information about venous thromboembolic events during follow-up. Twenty-two trials of statin versus control (105,759 participants) and seven trials of an intensive versus a standard dose statin regimen (40,594 participants) were included. In trials of statin versus control, allocation to statin therapy did not significantly reduce the risk of venous thromboembolic events (465 [0.9%] statin versus 521 [1.0%] control, odds ratio [OR] = 0.89, 95% CI 0.78-1.01, p = 0.08) with no evidence of heterogeneity between effects on deep vein thrombosis (266 versus 311, OR 0.85, 95% CI 0.72-1.01) and effects on pulmonary embolism (205 versus 222, OR 0.92, 95% CI 0.76-1.12). Exclusion of the trial result that provided the motivation for our meta-analysis (JUPITER) had little impact on the findings for venous thromboembolic events (431 [0.9%] versus 461 [1.0%], OR = 0.93 [95% CI 0.82-1.07], p = 0.32 among the other 21 trials). There was no evidence that higher dose statin therapy reduced the risk of venous thromboembolic events compared with standard dose statin therapy (198 [1.0%] versus 202 [1.0%], OR = 0.98, 95% CI 0.80-1.20, p = 0.87). Risk of bias overall was small but a certain degree of effect underestimation due to random error cannot be ruled out. Please see later in the article for the Editors' Summary.

CONCLUSIONS

The findings from this meta-analysis do not support the previous suggestion of a large protective effect of statins (or higher dose statins) on venous thromboembolic events. However, a more moderate reduction in risk up to about one-fifth cannot be ruled out.

Association between cardiovascular disease risk factors and occurrence of venous thromboembolism. A time-dependent analysis

Apart from obesity, it remains controversial whether atherosclerosis and its cardiovascular risk disease (CVD) factors are associated with risk of venous thromboembolism (VTE). Using data from the Atherosclerosis Risk in Communities study (ARIC), we evaluated associations between CVD risk factors and incident VTE in a cohort of 15,340 participants who were free a history of VTE and/or anticoagulant use on enrolment. The CVD risk factors were updated during the follow-up period. Over a mean follow-up time of 15.5 years (237,375 person-years), 468 participants had VTE events. Adjusting for demographic variables and body mass index (BMI), current smokers were at greater risk [HR of 1.44 (95% CI: 1.12-1.86)] compared to non-smokers. There was a positive monotonic association between BMI and VTE risk. Individuals with a BMI ≥35 kg/m² had a HR for VTE of 3.09 (95%CI: 2.26-4.23) compared to those with normal BMI (<25 kg/m²). Greater physical activity was associated with lower VTE risk in a demographic adjusted model; however, this association became non-significant following adjustment for BMI. Alcohol intake, diabetes, hypertension, high-density lipoprotein and low-density lipoprotein cholesterol, and triglycerides were not associated with VTE risk. In conclusion, among the well-established CVD risk factors, only current smoking and obesity were independently associated with VTE risk in this large cohort where risk factors were updated serially during follow-up. This finding corroborates that the pathogenesis of venous disease differs from that of atherosclerotic disease.

Lipid lowering drugs and the risk of recurrent venous thromboembolism

INTRODUCTION

Several studies have suggested that statins may lower the risk of venous thromboembolism (VTE), whereas fibrates may increase this risk. However, no studies have evaluated whether lipid-lowering drugs (LLD) use was associated with the risk of VTE recurrence.

MATERIALS AND METHODS

In a prospective cohort study, we followed-up all patients who had been treated for a first unprovoked VTE event in our centre. The association between LLD exposure and risk of recurrence of VTE after discontinuation of anticoagulation was analyzed with Cox proportional hazards model with adjustment for age, sex, body mass index, site of thrombosis, antiplatelets use, and duration of anticoagulation before inclusion in the study.

RESULTS

432 patients (median age 65.5 years interquartile range 45.0-75.0, 174 men) were followed up for a median of 29.5 months after discontinuation of anticoagulation. Sixty patients (13.9%) had recurrent VTE. During follow-up, 48 patients (11.1%) received statins, 36 patients (8.3%) received fibrates. In multivariate analysis, the risk of recurrent VTE associated with statin exposure was 1.02 (95% confidence interval 0.36-2.91) and 2.15 (95% confidence interval 1.01-4.61) for fibrate exposure.

CONCLUSION

Our results suggest an association between fibrate intake and an increased risk of recurrent VTE, whereas statin intake was not associated with recurrent VTE. Larger studies are needed to validate these results.

[Pathogenetic justification of statin use in ischaemic stroke prevention according to inflammatory theory in development of atherosclerosis]

There is an inflammatory component in the pathogenesis of ischaemic stroke, which plays an important role in inducing atherothrombotic and embolic stroke. Statins, HMG-CoA (3-hydroxy-3-methyl-glutaryl-coenzyme A) reductase inhibitors are widely used in the primary and secondary prevention of ischaemic stroke. It has been proved that beyond their main effect on inhibition of endogenous cholesterol, they also modify the inflammatory process. Additional benefits from the use of statins result from their effect on the immune system. Increased risk of recurrent vascular episodes and risk of death after statin withdrawal in patients with vascular disorders is connected with termination of the anti-inflammatory effect of these drugs. The authors highlight that because of the anti-inflammatory effect of statins it is reasonable to use them in all patients at risk of ischaemic stroke, including those with atrial fibrillation.

Frequency and predictors of symptomatic intracranial hemorrhage after intravenous thrombolysis for acute ischemic stroke in a Brazilian public hospital

OBJECTIVE

Scarce data are available on the occurrence of symptomatic intracranial hemorrhage related to intravenous thrombolysis for acute stroke in South America. We aimed to address the frequency and clinical predictors of symptomatic intracranial hemorrhage after stroke thrombolysis at our tertiary emergency unit in Brazil.

METHOD

We reviewed the clinical and radiological data of 117 consecutive acute ischemic stroke patients treated with intravenous thrombolysis in our hospital between May 2001 and April 2010. We compared our results with those of the Safe Implementation of Thrombolysis in Stroke registry. Univariate and multiple regression analyses were performed to identify factors associated with symptomatic intracranial transformation.

RESULTS

In total, 113 cases from the initial sample were analyzed. The median National Institutes of Health Stroke Scale score was 16 (interquartile range: 10-20). The median onset-to-treatment time was 188 minutes (interquartile range: 155-227). There were seven symptomatic intracranial hemorrhages (6.2%; Safe Implementation of Thrombolysis in Stroke registry: 4.9%; p = 0.505). In the univariate analysis, current statin treatment and elevated National Institute of Health Stroke Scale scores were related to symptomatic intracranial hemorrhage. After the multivariate analysis, current statin treatment was the only factor independently associated with symptomatic intracranial hemorrhage.

CONCLUSIONS

In this series of Brazilian patients with severe strokes treated with intravenous thrombolysis in a public university hospital at a late treatment window, we found no increase in the rate of symptomatic intracranial hemorrhage. Additional studies are necessary to clarify the possible association between statins and the risk of symptomatic intracranial hemorrhage after stroke thrombolysis.

Antibacterial activity of statins: a comparative study of atorvastatin, simvastatin, and rosuvastatin

Background

Statins have several effects beyond their well-known antihyperlipidemic activity, which include immunomodulatory, antioxidative and anticoagulant effects. In this study, we have tested the possible antimicrobial activity of statins against a range of standard bacterial strains and bacterial clinical isolates.

Methods

Minimum inhibitory concentrations (MIC) values were evaluated and compared among three members of the statins drug (atorvastatin, simvastatin, and rosuvastatin).

Results

It was revealed that statins are able to induce variable degrees of antibacterial activity with atorvastatin, and simvastatin being the more potent than rosuvastatin. Methicillin-sensitive staphylococcus aureus (MSSA), methicillin-resistant staphylococcus aureus (MRSA), vancomycin-susceptible enterococci (VSE), vancomycin-resistant enterococcus (VRE), acinetobacter baumannii, staphylococcus epidermidis, and enterobacter aerogenes, were more sensitive to both atorvastatin, and simvastatin compared to rosuvastatin. On the other hand, escherichia coli, proteus mirabilis, and enterobacter cloacae were more sensitive to atorvastatin compared to both simvastatin and rosuvastatin. Furthermore, most clinical isolates were less sensitive to statins compared to their corresponding standard strains.

Conclusion

Our findings might raise the possibility of a potentially important antibacterial class effect for statins especially, atorvastatin and simvastatin.

Prevention of VTE in nonsurgical patients: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

BACKGROUND

This guideline addressed VTE prevention in hospitalized medical patients, outpatients with cancer, the chronically immobilized, long-distance travelers, and those with asymptomatic thrombophilia.

METHODS

This guideline follows methods described in Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines in this supplement.

RESULTS

For acutely ill hospitalized medical patients at increased risk of thrombosis, we recommend anticoagulant thromboprophylaxis with low-molecular-weight heparin (LMWH), low-dose unfractionated heparin (LDUH) bid, LDUH tid, or fondaparinux (Grade 1B) and suggest against extending the duration of thromboprophylaxis beyond the period of patient immobilization or acute hospital stay (Grade 2B). For acutely ill hospitalized medical patients at low risk of thrombosis, we recommend against the use of pharmacologic prophylaxis or mechanical prophylaxis (Grade 1B). For acutely ill hospitalized medical patients at increased risk of thrombosis who are bleeding or are at high risk for major bleeding, we suggest mechanical thromboprophylaxis with graduated compression stockings (GCS) (Grade 2C) or intermittent pneumatic compression (IPC) (Grade 2C). For critically ill patients, we suggest using LMWH or LDUH thromboprophylaxis (Grade 2C). For critically ill patients who are bleeding or are at high risk for major bleeding, we suggest mechanical thromboprophylaxis with GCS and/or IPC at least until the bleeding risk decreases (Grade 2C). In outpatients with cancer who have no additional risk factors for VTE we suggest against routine prophylaxis with LMWH or LDUH (Grade 2B) and recommend against the prophylactic use of vitamin K antagonists (Grade 1B).

CONCLUSIONS

Decisions regarding prophylaxis in nonsurgical patients should be made after consideration of risk factors for both thrombosis and bleeding, clinical context, and patients' values and preferences.

Circulatory syndrome: an evolution of the metabolic syndrome concept!

The metabolic syndrome has been a useful, though controversial construct in clinical practice as well as a valuable model in order to understand the interactions of diverse cardiovascular risk factors. However the increasing importance of the circulatory system in particular the endothelium, in both connecting and controlling organ function has underlined the limitations of the metabolic syndrome definition. The proposed "Circulatory Syndrome" is an attempt to refine the metabolic syndrome concept by the addition of recently documented markers of cardiovascular disease including renal impairment, microalbuminuria, arterial stiffness, ventricular dysfunction and anaemia to more classic factors including hypertension, dyslipidemia and abnormal glucose metabolism; all of which easily measured in clinical practice. These markers interact with each other as well as with other factors such as aging, obesity, physical inactivity, diet and smoking. The final common pathways of inflammation, oxidative stress and hypercoagulability thereby lead to endothelial damage and eventually cardiovascular disease. Nevertheless, the Circulatory (MARC) Syndrome, like its predecessor the metabolic syndrome, is only a small step toward an understanding of these complex and as yet poorly understood markers of disease.

Statins for primary prevention of venous thromboembolism

BACKGROUND

Venous thromboembolism (VTE) is common in clinical practice. The efficacy of statins in the primary prevention of VTE remains unproven.

OBJECTIVES

To assess the efficacy of statins in the primary prevention of VTE.

SEARCH METHODS

The Cochrane Peripheral Vascular Diseases (PVD) Group searched their Specialised Register (last searched April 2011) and CENTRAL (2011, Issue 2). The authors searched MEDLINE (January 1966 to March 2011); EMBASE (1974 to March 2011); ISI Web of Knowledge (2001 to March 2011); the Chinese Biomedical Literature Database (1978 to March 2011) and other resources (including clinical trials registers, reference lists and presentations at various conferences.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that assessed statins were considered. The outcomes we evaluated were the rates of VTE, cardiovascular and cerebrovascular events, death and adverse events. Two authors independently selected RCTs against inclusion criteria. Disagreements were resolved by discussion with a third author.

DATA COLLECTION AND ANALYSIS

Data extraction was independently carried out by two authors. Disagreements were resolved by discussion with a third author. Two authors independently assessed the risk of bias according to a standard quality checklist provided by the PVD Group.

MAIN RESULTS

We included one RCT (17 citations) with 17,802 participants that assessed rosuvastatin for preventing VTE. Our analysis showed that rosuvastatin reduced the incidence of VTE (odds ratio (OR) 0.57, 95% confidence interval (CI) 0.37 to 0.86) and deep vein thrombosis (DVT) (OR 0.45, 95% CI 0.25 to 0.79), the risk of any (fatal and non-fatal) myocardial infarction (MI) (OR 0.45, 95% CI 0.30 to 0.69), any (fatal and non-fatal) stroke (OR 0.51, 95% CI 0.34 to 0.78), but did not reduce the incidence of pulmonary embolism (PE) (OR 0.77, 95% CI 0.41 to 1.46) and death after VTE (OR 0.50, 95% CI 0.20 to 1.24). Rosuvastatin did not reduce the incidence of any serious adverse event (OR 0.95, 95% CI 0.90 to 1.06).

AUTHORS' CONCLUSIONS

Available evidence showed that rosuvastatin was associated with a reduced incidence of VTE, but the evidence was limited to a single RCT. Randomised controlled trials of statins (including rosuvastatin) are needed to evaluate the efficacy of statins in the prevention of VTE.

Pharmacological actions of statins: a critical appraisal in the management of cancer

Statins, among the most commonly prescribed drugs worldwide, are cholesterol-lowering agents used to manage and prevent cardiovascular and coronary heart diseases. Recently, a multifaceted action in different physiological and pathological conditions has been also proposed for statins, beyond anti-inflammation and neuroprotection. Statins have been shown to act through cholesterol-dependent and -independent mechanisms and are able to affect several tissue functions and modulate specific signal transduction pathways that could account for statin pleiotropic effects. Typically, statins are prescribed in middle-aged or elderly patients in a therapeutic regimen covering a long life span during which metabolic processes, aging, and concomitant novel diseases, including cancer, could occur. In this context, safety, toxicity, interaction with other drugs, and the state of health have to be taken into account in subjects treated with statins. Some evidence has shown a dichotomous effect of statins with either cancer-inhibiting or -promoting effects. To date, clinical trials failed to demonstrate a reduced cancer occurrence in statin users and no sufficient data are available to define the long-term effects of statin use over a period of 10 years. Moreover, results from clinical trials performed to evaluate the therapeutic efficacy of statins in cancer did not suggest statin use as chemotherapeutic or adjuvant agents. Here, we reviewed the pharmacology of the statins, providing a comprehensive update of the current knowledge of their effects on tissues, biological processes, and pathological conditions, and we dissected the disappointing evidence on the possible future use of statin-based drugs in cancer therapy.

Lipid parameters, lipid lowering drugs and the risk of venous thromboembolism

BACKGROUND

Besides their effects on atherogenesis, lipids and lipoproteins could contribute to the development of venous thromboembolism (VTE). This association has been investigated in a few studies with conflicting results.

METHODS

Plasma levels of total cholesterol, triglycerides, HDL-cholesterol, LDL-cholesterol, apolipoprotein A-I and apolipoprotein B were measured in 467 patients with a first unprovoked VTE event diagnosed between May 2000 and December 2004 and in 467 age and sex matched controls. The association between these parameters and VTE was determined in non-users of lipid lowering drugs (LLD), in statin users and in fibrate users in a quartile-based analysis. We repeated this stratified analysis within each stratum of men and women.

RESULTS

The median age of patients was 73 years [interquartile range 58-80], 41.5% were men. Among the 934 patients of the study, 100 were treated with statin, 91 with fibrate and 743 were not receiving LLD. Among non users of LLD, high levels of apolipoprotein B were associated with VTE (OR 1.82, 95% CI 1.19-2.79) after adjustment for age and body mass index. Elevated LDL-cholesterol levels were associated with VTE only in men (OR 2.32, 95% CI 1.07-5.01). High levels of LDL/HDL-cholesterol and apolipoprotein B/apolipoprotein A-I ratios were associated with VTE (OR 2.76, 95% CI 1.69-4.50 and OR 1.86, 95% CI 1.16-2.97 respectively) but this effect was mainly observed in men. There was no association between lipid parameters and VTE in statin users and in fibrate users.

CONCLUSION

Our results are in line with the new concept of a global cardiovascular disease combining atherosclerosis and VTE.

Dose-related effect of statins in venous thrombosis risk reduction

BACKGROUND

Atherosclerosis and venous thromboembolism share similar pathophysiology based on common inflammatory mediators. The dose-related effect of statin therapy in venous thromboembolism remains controversial. This study investigated whether the use of antiplatelet therapy and statins decrease the occurrence of venous thromboembolism in patients with atherosclerosis.

METHODS

We conducted a retrospective cohort study reviewing 1795 consecutive patients with atherosclerosis admitted to a teaching hospital between 2005 and 2010. Patients who had been treated with anticoagulation therapy were excluded. Patients who either used statins for <2 months or never used them were allocated to the nonuser group.

RESULTS

The final analysis included 1100 patients. The overall incidence of venous thromboembolism was 9.7%. Among statin users, 6.3% (54/861) developed venous thromboembolism, compared with 22.2% (53/239) in the nonuser group (hazard ratio [HR] 0.24; P <.001). After controlling for confounding factors, statin use was still associated with a lower risk of developing venous thromboembolism (HR 0.29; P <.001). High-dose statin use (average 50.9 mg/day) (HR 0.25; P <.001) lowered the risk of venous thromboembolism compared with standard-dose statins (average 22.2 mg/day) (HR 0.38; P <.001). Dual antiplatelet therapy with aspirin and clopidogrel decreased occurrence of venous thromboembolism (HR 0.19; P <.001). Interestingly, combined statins and antiplatelet therapy further reduced the occurrence of venous thromboembolism (HR 0.16; P <.001).

CONCLUSIONS

The use of statins and antiplatelet therapy is associated with a significant reduction in the occurrence of venous thromboembolism with a dose-related response of statins.

Fibrin clot structure and function: a role in the pathophysiology of arterial and venous thromboembolic diseases

The formation of fibrin clots that are relatively resistant to lysis represents the final step in blood coagulation. We discuss the genetic and environmental regulators of fibrin structure in relation to thrombotic disease. In addition, we discuss the implications of fibrin structure for treatment of thrombosis. Fibrin clots composed of compact, highly branched networks with thin fibers are resistant to lysis. Altered fibrin structure has consistently been reported in patients with several diseases complicated by thromboembolic events, including patients with acute or prior myocardial infarction, ischemic stroke, and venous thromboembolism. Relatives of patients with myocardial infarction or venous thromboembolism display similar fibrin abnormalities. Low-dose aspirin, statins, lowering of homocysteine, better diabetes control, smoking cessation, and suppression of inflammatory response increase clot permeability and susceptibility to lysis. Growing evidence indicates that abnormal fibrin properties represent a novel risk factor for arterial and venous thrombotic events, particularly of unknown etiology in young and middle-aged patients.

Prehospital statin and aspirin use and the prevalence of severe sepsis and acute lung injury/acute respiratory distress syndrome

OBJECTIVES

To determine whether prehospital statin use is associated with a lower risk of sepsis, acute lung injury/acute respiratory distress syndrome, and mortality in critically ill patients. We also investigated the effect of combined prehospital use of both statins and aspirin.

DESIGN

Cross-sectional analysis of a prospective cohort.

PATIENTS

A total of 575 critically ill patients admitted to the medical or surgical intensive care unit of an academic tertiary-care hospital.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 575 patients, 149 (26%) were on statin therapy before hospitalization. A multivariable analysis including age, gender, current tobacco use, prehospital aspirin use, race, and Acute Physiology and Chronic Health Evaluation II score revealed that patients on statin therapy before hospitalization were less likely to have or develop severe sepsis (odds ratio 0.62, 95% confidence interval 0.40-0.96) or acute lung injury/acute respiratory distress syndrome (odds ratio 0.60, 95% confidence interval 0.36-0.99) during the first four intensive care unit days. In-hospital mortalities for patients with and without prehospital statin use (odds ratio 1.06, 95% confidence interval 0.62-1.83) were similar. Patients who had prehospital use of both statins and aspirin had the lowest rates of severe sepsis, acute lung injury/acute respiratory distress syndrome, and mortality.

CONCLUSIONS

Prehospital use of statins may be protective against sepsis and acute lung injury. This effect may be potentiated by prehospital aspirin use.

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.

A pilot study of the short-term use of simvastatin in sickle cell disease: effects on markers of vascular dysfunction

Sickle cell disease (SCD) is characterized by progressive vascular injury and its pathophysiology is strikingly similar to that of atherosclerosis. Statins decrease inflammation and improve endothelial function in cardiovascular disease, but their effect in SCD is not known. In this pilot study, we examined the safety and effect of short-term simvastatin on biomarkers of vascular dysfunction in SCD. We treated 26 SCD patients with simvastatin, 20 or 40 mg/d, for 21 d. Plasma nitric oxide metabolites (NOx), C-reactive protein (CRP), interleukin-6 (IL-6), vascular cell adhesion molecule-1 (VCAM-1), tissue factor (TF) and vascular endothelial growth factor (VEGF) were analyzed and responses to simvastatin were compared between the two treatment groups. Simvastatin increased NOx levels by 23% in the low-dose (P =0·01) and 106% in the moderate-dose (P =0·01) groups, and by 52% overall (P=0·0008). CRP decreased similarly in both dose groups and by 68% overall (P =0·02). Levels of IL-6 decreased by 50% (P=0·04) and 71% (P<0·05) in the low- and moderate-dose groups, respectively. Simvastatin had no effect on VEGF, VCAM1 or TF. Simvastatin was well-tolerated and safe. Our preliminary findings showing a dose-related effect of simvastatin on levels of NOx, CRP and IL-6 suggest a potential therapeutic role for simvastatin in SCD.

Statin effect on thrombin inhibitor effectiveness during percutaneous coronary intervention: a post-hoc analysis from the ISAR-REACT 3 trial

OBJECTIVE

To determine whether statin therapy influences the efficacy of thrombin inhibitor bivalirudin or unfractionated heparin (UFH) during PCI.

SETTING AND PATIENTS

The post-hoc analysis of the ISAR-REACT 3 Trial included 4,570 patients: 3,106 patients were on statin therapy and 1,464 patients were not on statin therapy at the time of PCI procedure.

MAIN OUTCOME MEASURES

The primary outcome of this analysis was the 30-day composite of death, myocardial infarction, target vessel revascularization (TVR) or major bleeding.

RESULTS

The primary outcome occurred in 7.9% patients (n = 246) in the statin group versus 9.8% (n = 143) in the non-statin group (P = 0.036). There was an interaction in univariate (P = 0.028) and multivariable (P = 0.026) analysis between pre-PCI statin therapy and the type of antithrombotic therapy regarding myocardial infarction. In the statin group, bivalirudin significantly reduced the incidence of major bleeding (2.6 vs. 4.3%, P = 0.013) with no significant difference in the incidence of myocardial infarction (4.9 vs. 5.2%; P = 0.73) compared with UFH. In the non-statin group, bivalirudin was inferior to UFH regarding the incidence of myocardial infarction (7.1 vs. 4.1%, P = 0.013), yet major bleeding remained lower among bivalirudin-treated patients (4.0 vs. 5.2%, P = 0.25).

CONCLUSION

This post-hoc analysis suggests the existence of an interaction between statin therapy before PCI and antithrombotic therapy during PCI. Patients receiving bivalirudin therapy at the time of PCI showed less periprocedural myocardial infarction when on pre-PCI statin therapy which has to be investigated in further studies.

Rosuvastatin Treatment is Associated with a Decrease of Serum Oxidised Low-Density Lipoprotein/Beta2-Glycoprotein I Complex Concentration in Type 2 Diabetes

Aims

To evaluate the effect of rosuvastatin on oxidised low-density lipoprotein/beta2-glycoprotein I (oxLDL/β2GPI) complex concentration in type 2 diabetes mellitus.

Methods

Open label 2:1 assignment of consecutive diabetic patients into oral rosuvastatin (10 mg daily for six weeks) arm or observational arm with measurements of serum oxLDL/|β2GPI complexes, nitric oxide metabolites, asymmetric dimethyl arginine, nitrotyrosine alongside routine biochemistry at baseline and end of study in all patients.

Results

After rosuvastatin treatment the mean serum concentration of oxLDL/β2GPI decreased from 0.79±0.49 units/mL to 0.53±0.36 units/mL (p<0.001). The decrease was statistically independent from the decrements of mean cholesterol, LDL and triglyceride concentrations (p<0.001) but probably dependent on the decrement of nitrate (p<0.001).

Conclusion

In type 2 diabetes, treatment with rosuvastatin was associated with a significant reduction of serum concentrations of oxLDL/β2GPI complexes, which is in further support of the already proposed effects of the drug on the oxidative metabolism of lipids and/or LDL. The oxLDL/β2GPI complex may represent a surrogate marker of oxidative stress in type 2 diabetes.

Simvastatin administration reduces thromboxane production in subjects taking aspirin: links between aspirin resistance and thrombin generation

BACKGROUND

Growing evidence indicates that statins may reduce thromboxane A(2) synthesis and thrombin generation. We investigated the relationships between thromboxane production, thrombin generation, and oxidative stress in patients receiving aspirin before and after statin administration.

METHODS

An open-label study was conducted in 112 men, aged 54.4 ± 7.3 years, at an increased cardiovascular risk receiving aspirin (75 mg/d). Prior to and following a 3-month simvastatin treatment (40 mg/d), we evaluated circulating thromboxane B(2) (TXB(2)), inflammatory markers, 8-isoprostane, and prothrombin fragment 1.2 (F1.2), a marker of thrombin generation, which was also measured in blood collected every 60s at the site of standardized skin incisions.

RESULTS

Subjects (n=28) with pretreatment TXB(2) concentrations in the highest quartile ("aspirin-resistant patients") were more frequently current smokers and had elevated C-reactive protein (CRP), interleukin-6, 8-isoprostane, shorter bleeding time, and increased F1.2 production in a model of microvascular injury, when compared with the 3 remaining quartiles (all, p<0.001). Simvastatin decreased serum TXB(2) in the whole group (by 20%, p=0.0008). Patients in the highest quartile of the baseline TXB(2) had still higher posttreatment TXB(2), CRP, interleukin-6, and F1.2 formation following injury (all, p<0.001). Simvastatin-induced change in TXB(2) correlated with the magnitude of changes in maximum levels and the velocity of F1.2 formation (all p<0.001) but not with changes in inflammatory markers or lipid profile.

CONCLUSIONS

The study shows that statins significantly reduce platelet TXA(2) formation in patients taking low-dose aspirin and this effect is associated with attenuated thrombin formation in response to vascular injury.

Statin use and the prevention of venous thromboembolism: a meta-analysis

AIMS

Statins are thought to have antithrombotic properties and may attenuate patients' odds of developing venous thromboembolism (VTE), but clinical studies have yielded variable estimates of this effect. The aim was to conduct a meta-analysis to evaluate the effect of statin use on development of VTE.

METHODS

Randomised controlled trials (RCTs) and observational studies evaluating the effects of statins on the incidence of VTE were selected from MEDLINE (1996 to August 2009), Cochrane CENTRAL (second quarter, 2009), Cochrane Database of Systematic Reviews (second quarter, 2009) and a manual review of references. While no further restrictions were placed on RCTs, observational studies were only included if they reported adjusted effect sizes using appropriate methods. Development of deep vein thrombosis (DVT), pulmonary embolism (PE) and any VTE from RCTs and observational studies were pooled using traditional meta analytic techniques with a random-effects model.

RESULTS

Ten studies were identified and eligible for meta-analysis. Upon meta-analysis, statin use was associated with a statistically significant reduction in the odds of developing VTE (AOR 0.68, 95% CI 0.54-0.86), DVT (AOR 0.59, 95% CI 0.43-0.82) and PE (AOR 0.70, 95% CI 0.53-0.94).

DISCUSSION

Statin use is associated with significantly reduced odds of developing VTE, DVT or PE by 32%, 41% and 30% respectively. Our meta-analysis included one RCT, JUPITER, which alone provided statistically significant reduction in the odds of developing VTE and DVT (43% and 55% respectively), and a nonsignificant reduction on PE.

CONCLUSION

Currently available evidence suggests that statins can reduce patients' odds of developing VTE.

Statins and the reduction of sudden cardiac death: antiarrhythmic or anti-ischemic effect?

Sudden cardiac death is an important cause of cardiovascular mortality with the majority of cases occurring in low-risk groups. HMG-CoA reductase inhibitors (statins) have recently been shown to reduce the incidence of ventricular tachycardia (VT)/fibrillation (VF) and sudden cardiac death, and this has been attributed to their pleiotropic effects. However, it is unclear whether this occurs through an 'indirect' anti-ischemic or 'direct' antiarrhythmic effect. We systematically reviewed articles published on MEDLINE between January 1996 and December 2009 focusing on the reduction of VT/VF and sudden cardiac death by statins and the potential mechanisms. Studies reporting sudden cardiac death or VT/VF outcomes with statin use (n = 23) or the pathophysiology of sudden cardiac death reduction by statins (n = 19) were included. We found that statins have been shown to reduce VT/VF and sudden cardiac death only in subjects with underlying coronary artery disease or ischemic cardiomyopathy. No definite benefits were seen with statins in sudden cardiac death and VT/VF in patients with non-ischemic cardiomyopathy. There is insufficient evidence to point toward a benefit in populations at low risk for VT/VF. In conclusion, an anti-ischemic rather than a primary antiarrhythmic effect emerges as the likely mechanism of sudden cardiac death reduction with statins.

Venous thromboembolism and subsequent diagnosis of subarachnoid hemorrhage: a 20-year cohort study

BACKGROUND

Venous thromboembolism is a predictor of subsequent risk of ischemic stroke and intracerebral hemorrhage, but no data are available regarding its association with risk of subarachnoid hemorrhage.

OBJECTIVES

To examine this issue, we conducted a nationwide cohort study in Denmark.

PATIENTS AND METHODS

Between 1977 and 2007, we identified 97,558 patients with a hospital diagnosis of venous thromboembolism and obtained information on risk of subsequent subarachnoid hemorrhage during follow-up in the Danish Registry of Patients. The incidence of subarachnoid hemorrhage in the venous thromboembolism cohort was compared with that of 453,406 population control cohort members.

RESULTS

For patients with pulmonary embolism (PE), there was clearly an increased risk of subarachnoid hemorrhage, both during the first year of follow-up [relative risk 2.69; 95% confidence interval (CI), 1.32-5.48] and during later follow-up of 2-20 years (relative risk 1.40; 95% CI, 1.05-1.87). For patients with deep venous thrombosis (DVT) the risk was likewise clearly increased during the first year of follow-up (relative risk 1.91; 95% CI, 1.13-3.22), but not during later follow-up (relative risk 1.04; 95% CI, 0.81-1.32).

CONCLUSIONS

We found evidence that PE is associated with an increased long-term risk of subarachnoid hemorrhage. The two diseases might share etiologic pathways affecting the vessel wall or share unknown risk factors.

C-reactive protein and risk of venous thromboembolism in the general population

OBJECTIVE

To examine the robustness of the association between C-reactive protein (CRP) levels and increased risk of venous thromboembolism (VTE) and to examine whether genetically elevated CRP levels cause VTE.

METHODS AND RESULTS

In the prospective Copenhagen City Heart Study, we observed 10 388 participants for longer than 16 years, of whom 484 developed a VTE. In the cross-sectional Copenhagen General Population Study, we studied 36 616 participants, of whom 903 previously had a VTE. Levels of CRP greater than 3 mg/L versus less than 1 mg/L were associated with a 2.3- and 2.4-fold increased risk of VTE in the Copenhagen City Heart Study and the Copenhagen General Population Study, respectively. CRP levels in tertiles, quintiles, and octiles associated with a stepwise increase in VTE risk. CRP genotypes associated with an increase in plasma CRP levels up to 59% but did not associate consistently with risk of VTE in either study. The causal odds ratio for VTE for a doubling in genetically elevated CRP on instrumental variable analyses was lower than the odds ratio for VTE observed for a doubling in plasma CRP on logistic regression ([odds ratio and 95% CI] 0.80 [0.56 to 1.12] versus 1.17 [1.08 to 1.27]; P=0.04).

CONCLUSIONS

We observed 47,000 participants from the general population, of whom 1387 developed VTE. Although elevated CRP levels robustly associated with increased risk of VTE, this may not necessarily be a causal association because genetically elevated CRP did not associate with VTE risk.

Primary prevention of vascular events in patients with high levels of C-reactive protein: the JUPITER study

The Justification for the Use of Statins in Primary Prevention: An Intervention Trial Evaluating Rosuvastatin (JUPITER) study was the first large-scale, prospective study to examine the benefits of statin therapy in subjects with elevated levels of high-sensitivity C-reactive protein but with low-to-normal LDL-cholesterol levels, who were not qualified for lipid-lowering treatment according to the current guidelines for primary prevention. The JUPITER study aimed to determine whether rosuvastatin 20 mg daily would reduce the rate of first major cardiovascular events, including cardiovascular death, nonfatal stroke, nonfatal myocardial infarction, hospitalization for unstable angina or arterial revascularization. Rosuvastatin reduced LDL-cholesterol levels by 50% and high-sensitivity C-reactive protein by 37%. Compared with placebo, the combined primary end point was reduced in 44% (p < 0.00001), and total mortality in 20% (p = 0.02). The trial confirmed the relationship between the rates of major cardiovascular events with both high-sensitivity C-reactive protein and LDL-cholesterol levels achieved after statin treatment. Interestingly, this was the first large, prospective statin trial to show benefit in the reduction of venous thromboembolism.

What is the optimum perioperative drug therapy following lower-extremity vein bypass surgery?

While endoluminal procedures are now commonly done for symptomatic peripheral arterial disease, vein bypass remains the gold standard for revascularization. Lower extremity vein bypass procedure success is dependent on patient factors, surgical judgment and technique, including use of medications. Cardioprotective medications have proven efficacy to decrease morbidity and mortality, but their use to improve graft patency is less well known. We review the up to date use of medications with known vascular effects that may promote graft success, as well as decrease cardiovascular events in this high risk patient group.

Statins and amyotrophic lateral sclerosis--the level of evidence for an association

Myopathy is a known side effect of statins, but neurotoxicity is not. Two studies reported that statins and amyotrophic lateral sclerosis (ALS) appear together more than expected amongst adverse events in overlapping surveillance databases. A pooled analysis of clinical trials, many with short follow-up, showed no higher rate of ALS in the statins arms. In older age groups, statin use increased from approximately 5% in 1991 to approximately 40% in 1998 and then remained constant. There was no similar increase in ALS incidence. The initial signals of a strong association from drug surveillance systems should now be discounted, but not disregarded.