Effectiveness of statins in reducing the rate of severe sepsis: a retrospective evaluation

Rosuvastatin Enhances Alveolar Fluid Clearance in Lipopolysaccharide-Induced Acute Lung Injury by Activating the Expression of Sodium Channel and Na,K-ATPase via the PI3K/AKT/Nedd4-2 Pathway

Background

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are devastating clinical conditions characterized by pulmonary epithelial damage and protein-rich fluid accumulation in the alveolar spaces. Statins are a class of HMG-CoA reductase inhibitors, which exert cholesterol-lowering and anti-inflammatory effects.

Methods

Rosuvastatin (1 mg/kg) was injected intravenously in rats 12 h before lipopolysaccharide (LPS, 10 mg/kg) administration. Eight hours later after LPS challenge, alveolar fluid clearance (AFC) was detected in rats (n = 6–8). Rosuvastatin (0.3 µmol/mL) and LPS were cultured with primary rat alveolar type II epithelial cells for 8 h.

Results

Rosuvastatin obviously improved AFC and attenuated lung-tissue damage in ALI model. Moreover, it enhanced AFC by increasing sodium channel and Na,K-ATPase protein expression. It also up-regulated P-Akt via reducing Nedd4-2 in vivo and in vitro. Furthermore, LY294002 blocked the increase in AFC in response to rosuvastatin. Rosuvastatin-induced AFC was found to be partly rely on sodium channel and Na,K-ATPase expression via the PI3K/AKT/Nedd4-2 pathway.

Conclusion

In summary, the findings of our study revealed the potential role of rosuvastatin in the management of ALI/ARDS.

Simvastatin Prevents Long-Term Cognitive Deficits in Sepsis Survivor Rats by Reducing Neuroinflammation and Neurodegeneration

Sepsis-associated encephalopathy causes brain dysfunction that can result in cognitive impairments in sepsis survivor patients. In previous work, we showed that simvastatin attenuated oxidative stress in brain structures related to memory in septic rats. However, there is still a need to evaluate the long-term impact of simvastatin administration on brain neurodegenerative processes and cognitive damage in sepsis survivors. Here, we investigated the possible neuroprotective role of simvastatin in neuroinflammation, and neurodegeneration conditions of brain structures related to memory in rats at 10 days after sepsis survival. Male Wistar rats (250-300 g) were submitted to cecal ligation and puncture (CLP, n = 42) or remained as non-manipulated (naïve, n = 30). Both groups were treated (before and after the surgery) by gavage with simvastatin (20 mg/kg) or an equivalent volume of saline and observed for 10 days. Simvastatin-treated rats that survived to sepsis showed a reduction in the levels of nitrate, IL1-β, and IL-6 and an increase in Bcl-2 protein expression in the prefrontal cortex and hippocampus, and synaptophysin only in the hippocampus. Immunofluorescence revealed a reduction of glial activation, neurodegeneration, apoptosis, and amyloid aggregates confirmed by quantification of GFAP, Iba-1, phospho Ser₃₉₆-tau, total tau, cleaved caspase-3, and thioflavin-S in the prefrontal cortex and hippocampus. In addition, treated animals presented better performance in tasks involving habituation memory, discriminative, and aversive memory. These results suggest that statins exert a neuroprotective role by upregulation of the Bcl-2 and gliosis reduction, which may prevent the cognitive deficit observed in sepsis survivor animals.

Repurposing of Existing Statin Drugs for Treatment of Microbial Infections: How Much Promising?

Today's microbial infections' resistance to approved drugs, the emergence of new infectious diseases and lack of vaccines, create a huge threat to human health. Thus, there is an urgent need to create novel antimicrobial agents, but the high cost and prolonged timeline of novel drug discovery and development is the major barrier to make new drugs. Therefore, there is a need for specific cost effective approaches in order to identify new drugs for the treatment of various microbial infections. Drug repurposition is an alternative technique to find existing clinically approved drugs for other indications. This approach may enhance the portfolio of Pharmaceutical companies by reducing the time and money required for the development of new chemical entity. In literature, various studies have reported some encouraging results regarding the antimicrobial use of existing statin drugs. Further, some clinical studies have also shown the protective effect of statin drugs in reduction of the morbidity and mortality due to many infectious diseases but complete understanding is still lacking. Thus, there is a need for better understanding of the use of statin drugs, especially in the context of antimicrobial effects. In this review, we try to summarize the use of statin drugs in various infectious diseases and their proposed antimicrobial mechanism of action. Further, current challenges and future perspectives of repurposition of statin drugs as antimicrobial agents have also been discussed.

Sulfated vizantin induces formation of macrophage extracellular traps

Vizantin is an insoluble adjuvant that activates macrophages and lymphocytes. Recently, 2,2',3,3',4,4'-hexasulfated-vizantin (sulfated vizantin), which enables solubilization of vizantin, was developed by the present team. Sulfated vizantin was found to enhance bactericidal activity against multi-drug resistant Pseudomonas aeruginosa in RAW264.7 cells. In addition, spread of P. aeruginosa was inhibited in RAW264.7 cells treated with sulfated vizantin. When only sulfated vizantin and P. aeruginosa were incubated, sulfated vizantin did not affect growth of P. aeruginosa. Formation of DNA-based extracellular traps (ETs), a novel defense mechanism in several types of innate immune cells, helps to eliminate pathogens. In the present study, ET-forming macrophages constituted the majority of immune cells. Sulfated vizantin induced ET formation in RAW264.7 cells, whereas a Ca-chelating reagent, EDTA, and T-type calcium channel blocker, tetrandrine, inhibited ET formation and attenuated inhibition of spread of P. aeruginosa in sulfated vizantin-treated cells. Thus, sulfated vizantin induces ET formation in phagocytic cells in a Ca-dependent manner, thus preventing spread of P. aeruginosa. Hence, sulfated vizantin may be useful in the management of infectious diseases.

Longitudinal study of short-term corticosteroid use by working-age adults with diabetes mellitus: Risks and mitigating factors

BACKGROUND

This study assessed the frequency of short-term oral corticosteroid use in adults with diabetes, examined the incidence of fractures, venous thromboembolism (VTE), and hospitalization for sepsis after corticosteroid use, and evaluated whether preventative medications mitigated adverse events.

METHODS

A longitudinal study (2012-14) was conducted of 1 548 945 adults (aged 18-64 years) who received healthcare coverage through a large national health insurer. Incidence rate ratios (IRR) were calculated using conditional Poisson regression.

RESULTS

Short-term oral corticosteroids were used by 23.9%, 20.8%, and 20.9% of adults with type 2 diabetes, type 1 diabetes, and no diabetes, respectively, during the 3-year period (P < 0.001). Baseline risks of fracture, VTE, and sepsis were greater for individuals with than without diabetes (P < 0.001). The combined effect of having diabetes and using corticosteroids was greater than the sum of the individual effects (synergy indices of 1.17, 1.23, 1.30 for fracture, VTE, and sepsis, respectively). The IRR for VTE in the 5-30 days after corticosteroid use was 3.62 (95% confidence interval [CI] 2.41-5.45). Fractures increased in the 5-30 days after corticosteroid use (IRR 2.06; 95% CI 1.52, 2.80), but concomitant use of ergocalciferol mitigated this risk (IRR 1.13; 95% CI 0.12, 11.07). The risk of hospitalization for sepsis was elevated with corticosteroid use (IRR 3.79; 95% CI 2.05, 7.01), but was mitigated by the concomitant use of statins.

CONCLUSIONS

Short-term oral corticosteroid use is common in adults with diabetes and is associated with an elevated, but low, risk of adverse events. The findings suggest that preventative medications may mitigate risk.

Development of a Physiologically Based Pharmacokinetic Modelling Approach to Predict the Pharmacokinetics of Vancomycin in Critically Ill Septic Patients

BACKGROUND AND OBJECTIVES

Sepsis is characterised by an excessive release of inflammatory mediators substantially affecting body composition and physiology, which can be further affected by intensive care management. Consequently, drug pharmacokinetics can be substantially altered. This study aimed to extend a whole-body physiologically based pharmacokinetic (PBPK) model for healthy adults based on disease-related physiological changes of critically ill septic patients and to evaluate the accuracy of this PBPK model using vancomycin as a clinically relevant drug.

METHODS

The literature was searched for relevant information on physiological changes in critically ill patients with sepsis, severe sepsis and septic shock. Consolidated information was incorporated into a validated PBPK vancomycin model for healthy adults. In addition, the model was further individualised based on patient data from a study including ten septic patients treated with intravenous vancomycin. Models were evaluated comparing predicted concentrations with observed patient concentration-time data.

RESULTS

The literature-based PBPK model correctly predicted pharmacokinetic changes and observed plasma concentrations especially for the distribution phase as a result of a consideration of interstitial water accumulation. Incorporation of disease-related changes improved the model prediction from 55 to 88% within a threshold of 30% variability of predicted vs. observed concentrations. In particular, the consideration of individualised creatinine clearance data, which were highly variable in this patient population, had an influence on model performance.

CONCLUSION

PBPK modelling incorporating literature data and individual patient data is able to correctly predict vancomycin pharmacokinetics in septic patients. This study therefore provides essential key parameters for further development of PBPK models and dose optimisation strategies in critically ill patients with sepsis.

Sepsis Mortality in Critical Care and Prior Statin Therapy: A Retrospective Cohort Study in Central Argentina

INTRODUCTION

Sepsis is a major public health problem, frequent, costly, and often fatal. Despite of improvements in supportive treatments the incidence of sepsis and the number of deaths related to sepsis is increasing. Statins have been recently proposed as adjuvants in the treatment of sepsis, but its effects on mortality show conflicting results worldwide.

AIM

The purpose of this study was to describe the clinical outcome of patients diagnosed with sepsis in a university-affiliated hospital in central Argentina and to evaluate it in relation to a group of septic patients with previous use of statins before the onset of sepsis.

MATERIALS AND METHODS

The present study was conducted as an observational retrospective research from April 2010 to December 2014 with patients over 18 years of age which were assigned to statins or control groups. Out of 2906 patients, 231 matched study and diagnostic criteria for sepsis and among them 33 (14.3%) belonged to the group of statins. The mean age was 64.2 ± 14.3 years.

RESULTS

The severity of sepsis on admission was as follows: Sepsis, n=147 (63.6%), Severe sepsis, n=26 (11.3%) and Septic shock, n=58 (25.1%). The mean length of stay in Intensive Care Unit (ICU) was10.8 ± 9.6 days and 21.2 ± 17 days in general hospital ward settings, without differences between groups of statin users and controls, p=0.873 and p=0.766, respectively. The in-hospital mortality rate was 31.2% (n=72). Previous statin use did not affect in-hospital or 30-day mortality (OR 0.978; 95% CI 0.339 to 2.274; p=0.789). Creatinine levels on days 3 and 14 were substantially higher in statins group (1.80 ±1.39 vs. 1.45 ± 1.47 mg/dl) (p=0.010) and (1.42 ± 1.14 vs. 1.09 ± 1.05 mg/dl) (p=0.009), respectively.

CONCLUSION

Prior use of statins did not reduce in-hospital or 30-day mortality in septic patients and it may be associated with impaired renal function in this group of Argentinian participants.

Effects of statins on the development of sepsis and organ dysfunction in hospitalized older patients in China

This study aimed to evaluate the protective role of statins on the development of sepsis and infection-related organ dysfunction and mortality in a hospitalized older Chinese population with bacterial infections. In this retrospective cohort study, 257 older patients with bacterial infection were divided into two groups: a statin group, those who had received statin therapy for ≥1 month before admission and continued receiving statin during hospitalization; and a non-statin group, those who had never received statin or used statin for <1 month prior to admission. A multivariate logistic regression analysis was performed to identify risk and protective factors for severe sepsis. A significantly lower incidence of organ dysfunction was found in the statin group, as compared with the non-statin group (13.3% vs 31.1%, respectively; p = 0.002), corresponding to adjusted rates ratio of 0.32 (95% confidence interval [CI], 0.13–0.75; p = 0.009). No significant difference was found between statin and non-statin groups in 30-day sepsis-related mortality (4.4% vs 10.2%, respectively; p = 0.109), incidence of intensive care unit admission (13.3% vs 16.8%, respectively; p = 0.469), or length of hospital stay (20.5 vs 25.9 days, respectively; p = 0.61). Statins significantly reduced the development of sepsis and infection-related organ dysfunction in hospitalized older Chinese patients but did not reduce 30-day mortality, ICU admission incidence, or length of hospital stay.

The Role of Statin Therapy in Sepsis

Objective:

To systematically review the evidence evaluating the role of statin therapy in sepsis.

Data Sources:

MEDLINE, EMBASE, and PubMed were searched (1980–January 2007) for English-language clinical trials that evaluated the use of statins and the development and treatment of sepsis in human subjects. Search terms included statin, HMG-CoA reductase inhibitor, bacteremia, sepsis, septic shock, septicemia, and severe sepsis. In addition, pertinent references from identified articles were obtained.

Study Selection and Data Extraction:

Only clinical trials with primary efficacy outcomes of mortality, incidence of sepsis, and severe sepsis were included.

Data Synthesis:

Seven retrospective and 2 prospective cohort studies were included in this review. One was excluded because the patient population was not experiencing sepsis. Three studies demonstrated a reduced mortality with statin use while 2 other studies did not demonstrate this mortality benefit. One study suggested increased mortality with statin use in sepsis. Three studies showed a reduced incidence of development of sepsis or sepsis-related outcomes, while one study did not. The observational and retrospective nature of these studies and the higher rate of cardiovascular comorbidities in the statin groups may have allowed for a confounding influence. The conflicting results and heterogeneity between the studies makes the observed association between statin use and incidence of sepsis and sepsis-related mortality inconclusive. The clinical benefit of statin therapy in sepsis remains to be determined.

Conclusions:

There is an association between statin use and a lower incidence of sepsis and sepsis-related mortality. However, a causal relationship between stalin use and reduced sepsis-related mortality has not yet been established. Currently, statins cannot be recommended for sepsis prevention or treatment until controlled trials are performed.

Is There Potential for Repurposing Statins as Novel Antimicrobials?

Statins are members of a class of pharmaceutical widely used to reduce high levels of serum cholesterol. In addition, statins have so-called "pleiotropic effects," which include inflammation reduction, immunomodulation, and antimicrobial effects. An increasing number of studies are emerging which detail the attenuation of bacterial growth and in vitro and in vivo virulence by statin treatment. In this review, we describe the current information available concerning the effects of statins on bacterial infections and provide insight regarding the potential use of these compounds as antimicrobial therapeutic agents.

Impact of statins in outcomes of septic patients: a systematic review

BACKGROUND

The pleiotropic effects of statins have prompted considerable research in fields other than cardiovascular disease. We reviewed the literature aiming to summarize and critically evaluate the current evidence about the potential use of statins in sepsis.

MATERIALS AND METHODS

We searched the Pubmed, SciELO, and Cochrane electronic databases from inception through November 1, 2013, for randomized controlled trials (RCTs) and cohort studies that examined the association between statin use (upon hospital admission or previous users) and the risk or outcome of sepsis. Data on study characteristics, measurement of statin use, and outcomes (adjusted for potential confounders) were extracted. We structured our review according to the Principles of Reporting in Systematic Reviews and Meta-Analysis criteria. Quality assessment of cohort studies was performed using the Ottawa-Newcastle Scale.

RESULTS

Twenty-three cohort studies and 5 RCTs were eligible, comprising 42 549 statin users and 54 201 non-statin users, from 1995 to 2013. The populations included varied from patients admitted to general wards or intensive care units with bacterial infections, community-acquired pneumonia, ventilator-associated pneumonia, bacteremia, or sepsis, to outpatients with chronic kidney disease or established cardiovascular disease. Overall, 16 studies reported a benefit from statin use in morbidity or mortality outcomes (range of adjusted odds ratio, 0.06-0.62; α = 0.05). The remaining 12 studies found no protective effect associated with statin use upon hospital admission or previous users. Among the 5 RCTs, none demonstrated a reduction in mortality.

CONCLUSION

There is insufficient evidence to support the use of statins in patients with sepsis, as the existing studies failed to prove a consistent mortality benefit. More clinical trials are warranted to provide more conclusive knowledge and ultimately change clinical practice.

Role of statin on mortality outcome in pneumonia patients: A meta-analysis

AIM: To determine the role of statin on mortality outcome in patient with pneumonia.

METHODS: For the present meta-analysis, we search the published literatures online through PubMed, Embase, Scopus and the Cochrane Library databases and the search words used were “statins’”, “bacteraemia”, “pneumonia”, and “ICU infections”. During the online search our focus was on full text articles, peer-reviewed, observational cohort or case control studies and randomized controlled trials. Those studies were selected whose outcome was hospital mortality among patients with pneumonia whether or not on statins. In this meta-analysis, 30 d mortality was used as the primary outcome as it has been demonstrated in the previous research that 30 d mortality is primarily because of community acquired pneumonia. As all studies were observational, where statin users were compared with historical rather than randomized controls, odds ratio for in-hospital or all-cause 30 d mortality was used as the primary effect measure used in the meta-analysis.

RESULTS: We came across the total 25 studies comprising 35355 patients (2734 statin users and 32621 statin non-users) during the electronic search. Four studies out of 25 were included in the final analysis. In this meta-analysis, when data regarding the use of statin in pneumonia patients on mortality was pooled, its results showed the non-significant effect of the statin on mortality outcome.

CONCLUSION: Although statins seems to be useful in the treatment of pneumonia patients but for statistical conclusion, further randomized controlled trials needs to be done or their results still waited to be published of ongoing trials, with the conclusion that presently statins showing no clinical benefit in the pneumonia patients.

Effect of the use of low and high potency statins and sepsis outcomes

INTRODUCTION

Although statins have been shown to have cholesterol-lowering effects, their pleiotropic benefits on sepsis remain a matter of debate. In addition, the influence of statin potency on sepsis-related mortality has never been explored. The aim of our study was to determine the sepsis outcomes of low- and high-potency statin users and non-users.

METHODS

This nationwide, population-based, propensity score-matched analysis used data from the linked administrative databases of Taiwan's National Health Insurance program. Patients were hospitalized for sepsis between 2000 and 2010. All-cause mortality and major adverse consequences of sepsis, such as in-hospital death, intensive care unit admission, shock events, and the use of mechanical ventilation, were assessed. Patients were divided into high-potency statin users (at least 10 mg rosuvastatin, at least 20 mg atorvastatin, or at least 40 mg simvastatin), low-potency statin users (all other statin treatments), and non-users.

RESULTS

A propensity score-matched cohort of 27,792 statin users and 27,792 non-users was included. Of 27,792 statin users, 9,785 (35.2 %) were treated with high-potency statins and 18,007 (64.8 %) were treated with low-potency statins. The 1-year mortality risk was significantly lower among both low-potency [adjusted hazard ratio (aHR) 0.89, 95 % confidence interval (CI) 0.85-0.93] and high-potency (aHR 0.80, 95 % CI 0.75-0.86) statin users compared with non-users. The risks of mortality and adverse consequences of sepsis were lower among high-potency than among low-potency statin users.

CONCLUSIONS

High-potency statin use is associated with a lower risk of sepsis-related mortality compared with low-potency statin use.

Are there any benefits from statin treatment for the septic patient?

Statins have become the most widely used drugs for lowering cholesterol levels worldwide. At least 20% of patients requiring admission to hospital are on established statin therapy, and this proportion is growing each year. Evidence from observational studies and basic science research suggests that statins might be associated with a reduced mortality in sepsis. Randomized trials are producing equivocal results but have not shown the marked improvement in outcome suggested by the observational studies. Continued use in current statin users appears a more fruitful area for future research than statin use de novo as an adjuvant therapy in sepsis. Statin use in patients with pneumonia, acute lung injury or early sepsis warrants further study. International practice of statin use in critically ill patients is variable, and potential toxicity mandates careful monitoring. Further studies are required to address fundamental issues such as efficacy, potential target patient populations, dose, class equivalence and safety.

Statins role in the prevention and treatment of sepsis

Sepsis is a complex disease with typically poor outcomes. While the onset of sepsis is typically infectious, the detrimental consequences follow pathogen toxin release that produces activation of numerous cytokines and a pro-inflammatory response. These same cytokines also stimulate activation of coagulation and inhibit natural fibrinolysis. Despite decades of research targeted against these pathways the development of sepsis and mortality in patients with sepsis remains high. While statins were developed for reducing cholesterol in patients with atherosclerotic disease, we now know they have a number of other properties which may be helpful in the prevention and treatment of sepsis. Statins have demonstrated the ability to reduce a number of pro-inflammatory cytokines known to be detrimental in the development and progression of sepsis. Statins have also demonstrated the ability to limit the coagulation response and promote fibrinolysis in the setting of sepsis. Based on these encouraging pharmacologic properties of statins a number of trials have been conducted evaluating the impact of statins on the prevention and treatment of sepsis. Most of the trials to date have been retrospective cohort trials, with very few prospective randomized trials. While some trials fail to demonstrate a benefit of statins, most trials suggest a reduction in the development of sepsis and/or other important sepsis related outcomes. While the laboratory and early clinical experience with statins are encouraging, randomized controlled trials will be need to fully define the role of statins in the prevention and treatment of sepsis.

Effect of statin therapy in the outcome of bloodstream infections due to Staphylococcus aureus: a prospective cohort study

INTRODUCTION

Statins have pleiotropic effects that could influence the prevention and outcome of some infectious diseases. There is no information about their specific effect on Staphylococcus aureus bacteremia (SAB).

METHODS

A prospective cohort study including all SAB diagnosed in patients aged ≥18 years admitted to a 950-bed tertiary hospital from March 2008 to January 2011 was performed. The main outcome variable was 14-day mortality, and the secondary outcome variables were 30-day mortality, persistent bacteremia (PB) and presence of severe sepsis or septic shock at diagnosis of SAB. The effect of statin therapy at the onset of SAB was studied by multivariate logistic regression and Cox regression analysis, including a propensity score for statin therapy.

RESULTS

We included 160 episodes. Thirty-three patients (21.3%) were receiving statins at the onset of SAB. 14-day mortality was 21.3%. After adjustment for age, Charlson index, Pitt score, adequate management, and high risk source, statin therapy had a protective effect on 14-day mortality (adjusted OR = 0.08; 95% CI: 0.01-0.66; p = 0.02), and PB (OR = 0.89; 95% CI: 0.27-1.00; p = 0.05) although the effect was not significant on 30-day mortality (OR = 0.35; 95% CI: 0.10-1.23; p = 0.10) or presentation with severe sepsis or septic shock (adjusted OR = 0.89; CI 95%: 0.27-2.94; p = 0.8). An effect on 30-day mortality could neither be demonstrated on Cox analysis (adjusted HR = 0.5; 95% CI: 0.19-1.29; p = 0.15).

CONCLUSIONS

Statin treatment in patients with SAB was associated with lower early mortality and PB. Randomized studies are necessary to identify the role of statins in the treatment of patients with SAB.

Statins decrease mortality in Lebanese patients with sepsis: A multicenter study

BACKGROUND

Sepsis is a significant public health concern. The clinical response to statins is variable among sepsis patients.

OBJECTIVE

The aim of the study was to determinate the effect of statin-treatment on mortality in Lebanese patients with sepsis.

METHODS

A retrospective multicenter study on Lebanese patients with sepsis between January 2008 and March 2012 was conducted. Patients with a primary diagnosis of sepsis admitted to the intensive care unit of two tertiary care hospitals in Beirut were included. Patients who continued to receive statin therapy for dyslipidemia during the hospital course were included in the statin treatment group. The control group consisted of patients not taking statin. Demographic characteristics, clinical signs, standard laboratory test and treatment received were compared between these two groups using univariate analysis. Logistic regression and survival analysis were performed by SPSS.

RESULTS

THREE HUNDRED FIFTY ONE LEBANESE PATIENTS WERE INCLUDED (AGE: 71.33 SD=14.97 years; Male: 56%). Among them, 30% took a statin at the doses recommended for dyslipidemia. The comparison of the two groups showed that in the statin treatment group: The mean serum level of C-reactive protein at the time of sepsis was significantly decreased (P=0.050), the length-stay at ICU significantly increased (P=0.047) and mortality significantly reduced (P<0.001). Results were confirmed by logistic regression, particularly for mortality. In the Cox regression analysis, hypothermia and shock were significantly associated with high mortality while statin treatment decreased mortality (hazard ratio = 0.540; 95% CI: 0.302-0.964; P=0.037).

CONCLUSIONS

At usual doses for dyslipidemia, statin treatment decreased incidence of mortality related to sepsis and improved the survival in this Lebanese septic population. Large randomized controlled clinical trials must be realized to give conclusive results about the potential beneficial effect of statins in sepsis.

Systematic review and meta-analysis on the association between outpatient statins use and infectious disease-related mortality

BACKGROUND

To update and refine systematic literature review on the association between outpatient statins use and mortality in patients with infectious disease.

MATERIALS AND METHODS

We searched articles published before September 31, 2012, on the association between statins and infectious disease-related mortality through electronic databases. Eligible articles were analyzed in Review Manager 5.1. We conducted stratification analysis by study design, infection types, clinical outcomes and study locations.

RESULTS

The pooled odds ratio (OR) for death (statins use vs. no use) across the 41 included studies was 0.71 (95% confidence interval: 0.64, 0.78). The corresponding pooled ORs were 0.58 (0.38, 0.90), 0.66 (0.57, 0.75), 0.71 (0.57, 0.89) and 0.83 (0.67, 1.04) for the case-control study, retrospective cohort studies, prospective cohort studies and RCTs; 0.40 (0.20, 0.78), 0.61 (0.41, 0.90), 0.69 (0.62, 0.78) and 0.86 (0.68, 1.09) for bacteremia, sepsis, pneumonia and other infections; 0.62 (0.534, 0.72), 0.68 (0.53, 0.89), 0.71 (0.61, 0.83) and 0.86 (0.70, 1.07) for 30-day, 90-day, in-hospital and long-term (>1 year) mortality, respectively.

CONCLUSIONS

Outpatient statins use is associated with a lower risk of death in patients with infectious disease in observational studies, but in a less extent in clinical trials. This association also varies considerably by infection types and clinical outcomes.

The association of prior statin use in septic shock treated with early goal directed therapy

BACKGROUND

Previous literature suggests statins may have a therapeutic role in sepsis. No data have examined if statin use may have a positive impact beyond that afforded by early goal directed therapy (EGDT).

OBJECTIVE

To test the hypothesis that previous statin use is associated with improved clinically relevant outcomes in patients with severe sepsis and septic shock receiving EGDT.

METHODS

Retrospective cohort study of 91 patients who presented in an academic center in severe sepsis or septic shock and received EGDT. Primary outcome was mortality and secondary outcomes included mechanical ventilation days, ICU length of stay, and hospital length of stay.

RESULTS

Patients (87 of 91) presented to the Emergency Department before ICU admission. Patients (18 of 91) were receiving statin therapy before presentation. The statin group had a mortality rate of 22.2 vs. 39.7% in the nonstatin group (P=0.273). The statin group had fewer mechanical ventilation days (8.49 vs. 7.29 days, P=0.026), and a trend in improved hospital length of stay (17.9 vs. 14.4 days, P=0.065), and ICU length of stay (7.15 vs. 4.89 days, P=0.077).

CONCLUSION

Prior statin use is associated with fewer mechanical ventilation days and a trend toward improvement in other clinically relevant outcomes. This trial is limited by its retrospective nature and small sample size. These results should serve as hypothesis generating for future prospective trials, as the lack of novel drug therapy and the mortality rate of septic shock both remain unacceptable.

Structural changes of the heart during severe sepsis or septic shock

Cardiovascular dysfunction is common in severe sepsis or septic shock. Although functional alterations are often described, the elevated serum levels of cardiac proteins and autopsy findings of myocardial immune cell infiltration, edema, and damaged mitochondria suggest that structural changes to the heart during severe sepsis and septic shock may occur and may contribute to cardiac dysfunction. We explored the available literature on structural (versus functional) cardiac alterations during experimental and human endotoxemia and/or sepsis. Limited data suggest that the structural changes could be prevented, and myocardial function improved by (pre-)treatment with platelet-activating factor, cyclosporin A, glutamine, caffeine, simvastatin, or caspase inhibitors.

Do aspirin and statins prevent severe sepsis?

PURPOSE OF REVIEW

Sepsis is an inflammatory condition associated with significant morbidity and mortality. Given the lack of specific therapies for the condition, prevention has garnered significant interest and increased importance. The article reviews the current literature regarding the use of aspirin and statins for the prevention of sepsis.

RECENT FINDINGS

Aspirin and statins have been integral in the prevention of atherosclerotic disease. Additionally, statins have proven beneficial in the prevention of nonatherosclerotic conditions secondary to their pleiotropic effects. In animal models, this pleiotropism modulates many inflammatory pathways of sepsis. The platelet also plays an integral role in this inflammatory cascade of sepsis. Scientific data indicates that antiplatelet therapy, including aspirin, may attenuate these undesirable effects of platelets. Finally, observational studies have shown that patients taking statins have a decreased incidence of sepsis and septic shock, and aspirin may potentiate these benefits.

SUMMARY

Sepsis is a deadly and costly condition with no available, specific treatment options. The statins and aspirin are well tolerated and widely used for prevention of cardiovascular disease. Because of their effects on the immune system and inflammatory pathways, they may present viable medical options for the prevention of sepsis.

Statins in the critically ill

The use or misuse of statins in critically ill patients recently attracted the attention of intensive care clinicians. Indeed, statins are probably the most common chronic treatment before critical illness and some recent experimental and clinical data demonstrated their beneficial effects during sepsis, acute lung injury (ALI)/acute respiratory distress syndrome (ARDS), or after aneurismal subarachnoidal hemorrhage (aSAH). Due to the heterogeneity of current studies and the lack of well-designed prospective studies, definitive conclusions for systematic and large-scale utilization in intensive care units cannot be drawn from the published evidence. Furthermore, the extent of statins side effects in critically ill patients is still unknown. For the intensive care clinician, it is a matter of individually identifying the patient who can benefit from this therapy according to the current literature. The purpose of this review is to describe the mechanisms of actions of statins and to synthesize the clinical data that underline the relevant effects of statins in the particular setting of critical care, in an attempt to guide the clinician through his daily practice.

The effect of rosuvastatin in a murine model of influenza A infection

RATIONALE

HMG-CoA reductase inhibitors such as rosuvastatin may have immunomodulatory and anti-inflammatory effects that may reduce the severity of influenza A infection. We hypothesized that rosuvastatin would decrease viral replication, attenuate lung injury, and improve mortality following influenza A infection in mice.

METHODS

C57Bl/6 mice were treated daily with rosuvastatin (10 mg/kg/day) supplemented in chow (or control chow) beginning three days prior to infection with either A//Udorn/72 [H3N2] or A/WSN/33 [H1N1] influenza A virus (1×10(5) pfu/mouse). Plaque assays were used to examine the effect of rosuvastatin on viral replication in vitro and in the lungs of infected mice. We measured cell count with differential, protein and cytokines in the bronchoalveolar lavage (BAL) fluid, histologic evidence of lung injury, and wet-to-dry ratio on Day 1, 2, 4, and 6. We also recorded daily weights and mortality.

RESULTS

The administration of rosuvastatin had no effect on viral clearance of influenza A after infection. Weight loss, lung inflammation and lung injury severity were similar in the rosuvastatin and control treated mice. In the mice infected with influenza A (A/WSN/33), mortality was unaffected by treatment with rosuvastatin.

CONCLUSIONS

Statins did not alter the replication of influenza A in vitro or enhance its clearance from the lung in vivo. Statins neither attenuated the severity of influenza A-induced lung injury nor had an effect on influenza A-related mortality. Our data suggest that the association between HMG CoA reductase inhibitors and improved outcomes in patients with sepsis and pneumonia are not attributable to their effects on influenza A infection.

Statins in sepsis

Sepsis is a common intensive care unit event occurring in approximately 750 000 patients annually, with a case mortality rate approaching 50%. Sepsis is characterized by a chaotic and excessive release of inflammatory cytokines and procoagulants including tumor necrosis factor, interleukin (IL)-1, IL-6, IL-8, platelet-activating factor, and tissue factor. Efforts to inhibit individual cytokines in order to modify poor outcomes have been generally disappointing, suggesting the need to target multiple inflammatory mediators to obtain clinical benefit. Statins lower lipids by inhibiting 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, which in turn inhibits the rate-limiting step in cholesterol biosynthesis. In addition to lowering total cholesterol, statins have pleiotropic effects on inflammation and immunity. Instead of impacting a single entity in the sepsis syndrome, statins may have positive effects on multiple inflammatory, immunomodulating, and coagulation targets involved in the development of infection and sepsis. There have been a number of institutional- and population-based studies that have evaluated the impact of statins in patients with infection and sepsis. Most of these studies, but not all, have demonstrated a number of positive outcomes in patients with statins, including reduction in mortality. Based on these data, statins are a promising therapy in the management of patients with sepsis and warrant larger and more rigorous clinical trials.

Association between statin therapy and outcomes in critically ill patients: a nested cohort study

Background

The effect of statin therapy on mortality in critically ill patients is controversial, with some studies suggesting a benefit and others suggesting no benefit or even potential harm. The objective of this study was to evaluate the association between statin therapy during intensive care unit (ICU) admission and all-cause mortality in critically ill patients.

Methods

This was a nested cohort study within two randomised controlled trials conducted in a tertiary care ICU. All 763 patients who participated in the two trials were included in this study. Of these, 107 patients (14%) received statins during their ICU stay. The primary endpoint was all-cause ICU and hospital mortality. Secondary endpoints included the development of sepsis and severe sepsis during the ICU stay, the ICU length of stay, the hospital length of stay, and the duration of mechanical ventilation. Multivariate logistic regression was used to adjust for clinically and statistically relevant variables.

Results

Statin therapy was associated with a reduction in hospital mortality (adjusted odds ratio [aOR] = 0.60, 95% confidence interval [CI] 0.36-0.99). Statin therapy was associated with lower hospital mortality in the following groups: patients >58 years of age (aOR = 0.58, 95% CI 0.35-0.97), those with an acute physiology and chronic health evaluation (APACHE II) score >22 (aOR = 0.54, 95% CI 0.31-0.96), diabetic patients (aOR = 0.52, 95% CI 0.30-0.90), patients on vasopressor therapy (aOR = 0.53, 95% CI 0.29-0.97), those admitted with severe sepsis (aOR = 0.22, 95% CI 0.07-0.66), patients with creatinine ≤100 μmol/L (aOR = 0.14, 95% CI 0.04-0.51), and patients with GCS ≤9 (aOR = 0.34, 95% CI 0.17-0.71). When stratified by statin dose, the mortality reduction was mainly observed with statin equipotent doses ≥40 mg of simvastatin (aOR = 0.53, 95% CI 0.28-1.00). Mortality reduction was observed with simvastatin (aOR = 0.37, 95% CI 0.17-0.81) but not with atorvastatin (aOR = 0.80, 95% CI 0.84-1.46). Statin therapy was not associated with a difference in any of the secondary outcomes.

Conclusion

Statin therapy during ICU stay was associated with a reduction in all-cause hospital mortality. This association was especially noted in high-risk subgroups. This potential benefit needs to be validated in a randomised, controlled trial.

Statins in prevention and treatment of severe sepsis and septic shock

Severe sepsis is an infection-induced inflammatory syndrome that can lead to multi-organ dysfunction and continues to be a major cause of morbidity and mortality worldwide. Because numerous cascades are triggered during sepsis, selective blocking of inflammatory mediators may be insufficient to arrest this process, and recent therapeutic approaches have proven controversial. Statins are the most commonly prescribed agents for hypercholesterolaemia and dominate the area of cardiovascular risk reduction. Moreover, these drugs have a variety of actions that are independent of their lipid lowering effect. Such anti-inflammatory, antioxidant, immunomodulatory, and antiapoptotic features have been collectively referred to as pleiotropic effects. By virtue of their pleiotropic effects, statins have also emerged as potentially useful in various critical care areas such as bacteraemia, the early phases of sepsis and septic shock, as well as the management of serious infections. This review outlines current evidence on the use of statins for preventing and treating sepsis.

Statins enhance formation of phagocyte extracellular traps

Statins are inhibitors of 3-hydroxy 3-methylglutaryl coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme in cholesterol biosynthesis. Recent clinico-epidemiologic studies correlate patients receiving statin therapy with having reduced mortality associated with severe bacterial infection. Investigating the effect of statins on the innate immune capacity of phagocytic cells against the human pathogen Staphylococcus aureus, we uncovered a beneficial effect of statins on bacterial clearance by phagocytes, although, paradoxically, both phagocytosis and oxidative burst were inhibited. Probing instead for an extracellular mechanism of killing, we found that statins boosted the production of antibacterial DNA-based extracellular traps (ETs) by human and murine neutrophils and also monocytes/macrophages. The effect of statins to induce phagocyte ETs was linked to sterol pathway inhibition. We conclude that a drug therapy taken chronically by millions alters the functional behavior of phagocytic cells, which could have ramifications for susceptibility and response to bacterial infections in these patients.

Statin therapy and decreased incidence of positive Candida cultures among patients with type 2 diabetes mellitus undergoing gastrointestinal surgery

OBJECTIVE

To assess whether statin therapy decreases the incidence of cultures positive for Candida species among high-risk hospitalized patients with type 2 diabetes mellitus (DM).

PATIENTS AND METHODS

We performed a retrospective cohort study analyzing the records of all patients with type 2 DM who were admitted to Massachusetts General Hospital for lower gastrointestinal tract surgery between January 1, 2001, and May 1, 2008. We defined statin exposure as the filling of at least 1 prescription of statins during the 6 months before hospitalization or during the current hospital stay. The primary outcome was a culture positive for Candida species during hospitalization. Clinical information on a wide range of covariates was collected. Logistic regression analysis was used to adjust for possible confounders.

RESULTS

Of the 1019 patients who were eligible for the study, 493 (48%) were receiving statins. A total of 139 patients (14%) had at least 1 culture positive for Candida species during hospitalization. An adjusted multivariate model based on a backward stepwise elimination procedure showed that statin therapy significantly decreased the incidence of cultures positive for Candida species (odds ratio, 0.60; 95% confidence interval [CI], 0.38-0.96; P=.03) with a statistically significant prolonged time to event compared with no statin therapy (adjusted hazard ratio, 0.62; 95% CI, 0.44-0.88; P=.01). The benefit of statins was more prominent in patients with type 2 DM who had greater comorbidities (Charlson Comorbidity Index ≥2) (adjusted odds ratio, 0.47; 95% CI, 0.27-0.79; P=.01).

CONCLUSION

Among patients with type 2 DM who underwent gastrointestinal surgery, use of statins correlated with a decreased incidence of cultures positive for Candida species.

Simvastatin attenuates ventilator-induced lung injury in mice

INTRODUCTION

Mechanical ventilation (MV) is a life saving intervention in acute respiratory failure without alternative. However, particularly in pre-injured lungs, even protective ventilation strategies may evoke ventilator-induced lung injury (VILI), which is characterized by pulmonary inflammation and vascular leakage. Adjuvant pharmacologic strategies in addition to lung protective ventilation to attenuate VILI are lacking. Simvastatin exhibited anti-inflammatory and endothelial barrier stabilizing properties in vitro and in vivo.

METHODS

Mice were ventilated (12 ml/kg; six hours) and subjected to simvastatin (20 mg/kg) or sham treatment. Pulmonary microvascular leakage, oxygenation, pulmonary and systemic neutrophil and monocyte counts and cytokine release in lung and blood plasma were assessed. Further, lung tissue was analyzed by electron microscopy.

RESULTS

Mechanical ventilation induced VILI, displayed by increased pulmonary microvascular leakage and endothelial injury, pulmonary recruitment of neutrophils and Gr-1high monocytes, and by liberation of inflammatory cytokines in the lungs. Further, VILI associated systemic inflammation characterized by blood leukocytosis and elevated plasma cytokines was observed. Simvastatin treatment limited pulmonary endothelial injury, attenuated pulmonary hyperpermeability, prevented the recruitment of leukocytes to the lung, reduced pulmonary cytokine levels and improved oxygenation in mechanically ventilated mice.

CONCLUSIONS

High-dose simvastatin attenuated VILI in mice by reducing MV-induced pulmonary inflammation and hyperpermeability.

Statins in candidemia: clinical outcomes from a matched cohort study

Background

HMG CoA reductase inhibitors (statins) in patients with bacteremic sepsis have shown significant survival benefits in several studies. There is no data on the effect of statins in candidemic patients, however in-vitro models suggest that statins interfere with ergesterol formation in the wall of yeasts.

Methods

This retrospective matched- cohort study from 1/2003 to 12/2006 evaluated the effects of statins on patients with candidemia within intensive care units. Statin-users had candidemia as a cause of their systemic inflammatory response and were on statins throughout their antifungal therapy, while non-statin users were matched based on age +/- 5 years and co-morbid factors. Primary analysis was 30-day survival or discharge using bivariable comparisons. Multivariable comparisons were completed using conditional logistic regression. All variables with a p-value less than 0.10 in the bivariable comparisons were considered for inclusion in the conditional logistic model.

Results

There were 15 statin-users and 30 non-statin users that met inclusion criteria, all with similar demographics and co-morbid conditions except the statin group had more coronary artery disease (P < 0.01) and peripheral vascular disease (P = 0.03) and lower median APCAHE II scores (14.6 vs 17, p = 0.03). There were no differences in duration of candidemia, antifungal therapy or Candida species between the groups. Statins were associated with lower mortality on bivariable (OR 0.09, 95% CI 0.11-0.75, p = 0.03) and multivariable (OR 0.22, 95% CI 0.02-2.4, p = 0.21) analyses compared to controls; although, in the latter the protective effect lacked statistical signficance.

Conclusion

In our small, single-center matched-cohort study, statins may provide a survival benefit in candidemia, however further studies are warranted to validate and further explore this association.

Statin treatment and mortality in bacterial infections--a systematic review and meta-analysis

BACKGROUND

Several studies have reported improved survival in severe bacterial infections among statin treated patients. In addition, statins have been ascribed beneficial anti-inflammatory effects. The aim of this study was to evaluate the effect of statin-treatment on mortality in patients with bacterial infections, by means of a systematic review and a meta-analysis.

METHODOLOGY AND PRINCIPAL FINDINGS

Studies investigating the association between statin use and mortality in patients with bacterial disease were identified in a systematic literature review and a meta-analysis was performed to calculate the overall odds ratio of mortality in statin users. The literature search identified 947 citations from which 40 relevant studies were extracted. In all, 15 studies comprising 113,910 patients were included in the final analysis. Statin use was associated with a significantly (p<0.0001) reduced mortality in patients suffering from bacterial infections (OR 0.52, 95% CI 0.42-0.66). However, all studies included were of observational design and funnel plot analyses indicated influence by a possible publication bias (Egger's bias test p<0.05). When a precision estimate test was used to adjust for publication bias the effect of statin treatment was no longer significant, with an OR of 0.79 (95% CI 0.58-1.07).

CONCLUSION/SIGNIFICANCE

According to the meta-analysis of observational studies presented here, patients on statin therapy seem to have a better outcome in bacterial infections. However, the association did not reach statistical significance after adjustment for apparent publication bias. Thus, there is a great need for randomised controlled trials investigating the possible beneficial effect of statins in bacterial infections.

The effect of statins on mortality from severe infections and sepsis: a systematic review and meta-analysis

PURPOSE

The aim of this study was to systematically review the literature on the effect of statins on mortality in patients with infection and/or sepsis.

MATERIALS AND METHODS

MEDLINE, EMBASE, PapersFirst, and the Cochrane collaboration and the Cochrane Register of controlled trials were searched and were current as of December 2009. Randomized, double-blind or single-blind, placebo-controlled studies; observational cohort studies (retrospective and prospective); and case-controlled studies were included. Types of participants included adult and pediatric subjects with sepsis or various other types of infection. Exposure was defined as the use of a statin for any indication. The primary outcome chosen was mortality from any cause, and secondary outcomes included 30-day mortality, in-hospital mortality, mortality from pneumonia, mortality from bacteremia, mortality from sepsis, and mortality from mixed infection.

RESULTS

A total of 20 studies were included in the analysis, 18 being cohort studies (12 retrospective, 6 prospective), 1 matched cohort study with 2 case-control studies, and 1 randomized control trial. Meta-analysis for various infection-related outcomes revealed the following pooled odds ratios all in favor of statin use vs non: 0.61 (95% confidence interval [CI], 0.48-0.73) for 30-day mortality (n = 7), 0.38 (95% CI, 0.13-0.64) for in-hospital mortality (n = 7), 0.63 (95% CI, 0.55-0.71) for pneumonia-related mortality (n = 7), 0.33 (95% CI, 0.09-0.75) for bacteremia-related mortality (n = 4), 0.40 (95% CI, 0.23-0.57) for sepsis-related mortality (n = 4), and 0.50 (95% CI, 0.18-0.83) for mixed infection-related mortality (n = 4).

CONCLUSIONS

This meta-analysis demonstrated a protective effect for statins in patients with sepsis and/or other infections compared to placebo for various infection-related outcomes. However, our results are limited by the cohort design of the selected studies and the degree of heterogeneity among them, and as a result, further randomized trials are needed to validate the use of statins for sepsis and/or other infections.

Statin use does not affect the outcome of acute infection: a prospective cohort study

Statins are used to prevent atherosclerosis because of their hypolipemic effects. In vitro testing and murine models suggest that statins may affect outcome in sepsis. Our meta-analysis of epidemiological studies in humans confirms that previous statin use appears to have a protective effect on infection rates and outcomes. The studies considered, however, were very different and heterogeneity was high, especially for mortality criteria.

OBJECTIVE

To compare outcome for current statin users and nonusers hospitalized with fever, under pragmatic circumstances.

DESIGN

Prospective cohort study.

SETTING

University Hospital of Brest (France).

PARTICIPANTS

Febrile (>38 degrees C) patients older than 40 years, admitted to the hospital on an emergency basis in 2005. Patients' outcome was compared according to their exposure to statins (current user or nonuser).

MAIN OUTCOME MEASURES

Mortality, length of hospitalization, admission to ICU and to convalescent homes

RESULTS

Of 40 343 patients referred for admission by the emergency department in 2005, 964 patients older than 40 years had a fever higher than 38 degrees C and were included in the study. Statin-user status, however, was available for only 921. The ICU admission rate (relative risk: 4.69; 95% CI: 2.42-9.08) was significantly higher (p=0.009) among statin users (n=139) than nonusers (n=782). The groups had similar lengths of hospitalization and similar rates of mortality and of convalescent home admissions.

CONCLUSION

Our study does not confirm that statin use affects infection outcome and suggests that previous findings may be associated instead with more cautious care or nonspecific cardiovascular prevention rather than with a specific infection-related effect. Thus, these data support the continuation of statin therapy during physiological aggression, including infection.

Farnesyltransferase inhibitor improved survival following endotoxin challenge in mice

Endotoxemia plays an important role in the pathogenesis of sepsis and is accompanied by dysregulated apoptosis of immune and non-immune cells. Treatment with statins reduces mortality in rodent models of sepsis and endotoxemia. Inhibition of protein isoprenylation, including farnesylation, has been proposed as a mechanism to mediate the lipid-lowering-independent effects of statins. Nonetheless, the effects of the inhibition of isoprenylation have not yet been studied. To investigate the role of farnesylation, we evaluated the effects of farnesyltransferase inhibitor and statin on survival following lipopolysaccharide (LPS) challenge in mice. Both simvastatin (2mg/kg BW) and FTI-277 (20mg/kg BW) treatment improved survival by twofold after LPS injection, as compared with vehicle alone (p<0.01). LPS-induced cleavage (activation) of caspase-3, an indicator of apoptotic change, and increased protein expression of proapoptotic molecules, Bax and Bim, and activation of c-Jun NH(2)-terminal kinase (JNK/SAPK) in the liver and spleen were attenuated by both simvastatin and FTI-277. These results demonstrate that farnesyltransferase inhibitor as well as statin significantly reduced LPS-induced mortality in mice. Our findings also suggest that inhibition of protein farnesylation may contribute to the lipid-lowering-independent protective effects of statins in endotoxemia, and that protein farnesylation may play a role in LPS-induced stress response, including JNK/SAPK activation, and apoptotic change. Our data argue that farnesyltransferase may be a potential molecular target for treating patients with endotoxemia.

Reduction in mortality associated with statin therapy in patients with severe sepsis

STUDY OBJECTIVE

To evaluate the effect of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) on mortality in patients with severe sepsis.

DESIGN

Retrospective cohort study.

SETTING

Intensive care unit (ICU) of an academic medical center.

PATIENTS

One hundred eighty-eight patients aged 40 years or older with a diagnosis of severe sepsis and an ICU stay between January 1, 2005, and December 31, 2006.

MEASUREMENTS AND MAIN RESULTS

Patient demographic data, statin use, and Acute Physiology and Chronic Health Evaluation (APACHE) II scores at the time of sepsis diagnosis were collected from the patient database. We used a multivariable logistic regression model to evaluate the association between statin use and in-hospital all-cause mortality after controlling for age, sex, and severity of illness. Of the 188 patients who met our inclusion criteria, 60 (32%) had statin exposure. Patients receiving statins were similar in age, sex, and APACHE II scores to those not receiving statins. In the univariable comparison, the statin group had a 35% relative reduction in mortality compared with the nonstatin group (mortality rate 31.7% vs 48.4%, p=0.040). Most of the mortality reduction attributed to statins occurred in patients with APACHE II scores higher than 24 (mortality rate 32.3% vs 57.5%, p=0.031), with a minimal mortality difference in patients with APACHE II scores of 24 or lower (31% vs 36.4%, p=0.810). In the multivariable regression model, statin use had a protective effect (odds ratio [OR] 0.42, 95% confidence interval [CI] 0.21-0.84, p=0.014), whereas increasing age (OR 1.03, 95% CI 1.01-1.06, p=0.013) and higher APACHE II score (OR 1.11, 95% CI 1.05-1.18, p=0.001) were associated with increased mortality.

CONCLUSION

The use of statins was associated with a protective effect in patients with severe sepsis, as demonstrated by a significant reduction in mortality compared with patients not receiving statins.

Statins for sepsis: a critical and updated review

There is increasing discussion of a potential role for statins in the management of sepsis. A search of PubMed, Embase, Scopus and the Cochrane Library databases was performed by combining the terms 'statins', 'infection', 'sepsis', 'bacteraemia', 'pneumonia', and 'ICU infections'. A total of 22 studies were retrieved, which included 177,260 people and compared clinical outcomes between 51,193 statin users and 126,067 non-statin users. Nineteen were cohort studies (seven prospective and 12 retrospective), two were retrospective case-control studies, and one was a randomized controlled study. Nine studies examined the use of statins in sepsis, four in community-acquired pneumonia (CAP), three in bacteraemia, and three in post-operative patients. Mortality data were presented in 15 studies; in ten, mortality was lower among statin users (three of six sepsis studies, five of six CAP studies, and two of three bacteraemia studies). In four studies, there was no difference in mortality (two of six sepsis studies, one of six CAP studies, and one of three bacteraemia studies) and in one study there was increased mortality among septic intensive-care unit patients receiving statins. Five of the nine studies that examined the risk of developing sepsis/infection as a primary outcome (six of nine sepsis studies and all studies in the postoperative setting) found a decreased risk among statin users, whereas the remaining studies found no difference. Irrespective of their design (matched vs. non-matched), the majority of the studies suggested that statins have a beneficial effect on the outcome of infection; however, their observational design does not allow us to draw firm conclusions. The clinical benefit of statin therapy in sepsis remains to be determined by ongoing randomized controlled trials.

Novel uses for statins in surgical patients

BACKGROUND

Aside from their cholesterol-lowering effects statins are known to have a range of other 'pleiotropic' effects. We present an overview of the basic science behind these effects and then review clinical trials and the current role of statins relevant to modern surgical practice.

METHODS

A systematic review of the literature was performed using the keywords surgery and the MeSH term for statins. All clinical studies relating to statin use in surgical patients were evaluated. An overview of the literature on statin use and cardiac outcomes was performed.

CONCLUSIONS

Statins are safe and have a wide range of pleiotropic effects relevant to surgical practice. Strongest evidence for their clinical use comes in primary cardiac risk reduction in many types of vascular surgery. There is a large body of evidence showing their benefit perioperatively in high-risk vascular and cardiac surgery but the picture is less clear for low-risk patients. Further studies are needed to evaluate exact dosage regimes and timing of administration. Novel uses of their anti-inflammatory properties in sepsis and vasomotor properties in subarachnoid haemorrhage are being further investigated by randomised trials.

Iron behaving badly: inappropriate iron chelation as a major contributor to the aetiology of vascular and other progressive inflammatory and degenerative diseases

BACKGROUND

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular 'reactive oxygen species' (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation.

REVIEW

We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation).The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible.This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, since in some circumstances (especially the presence of poorly liganded iron) molecules that are nominally antioxidants can actually act as pro-oxidants. The reduction of redox stress thus requires suitable levels of both antioxidants and effective iron chelators. Some polyphenolic antioxidants may serve both roles.Understanding the exact speciation and liganding of iron in all its states is thus crucial to separating its various pro- and anti-inflammatory activities. Redox stress, innate immunity and pro- (and some anti-)inflammatory cytokines are linked in particular via signalling pathways involving NF-kappaB and p38, with the oxidative roles of iron here seemingly involved upstream of the IkappaB kinase (IKK) reaction. In a number of cases it is possible to identify mechanisms by which ROSs and poorly liganded iron act synergistically and autocatalytically, leading to 'runaway' reactions that are hard to control unless one tackles multiple sites of action simultaneously. Some molecules such as statins and erythropoietin, not traditionally associated with anti-inflammatory activity, do indeed have 'pleiotropic' anti-inflammatory effects that may be of benefit here.

CONCLUSION

Overall we argue, by synthesising a widely dispersed literature, that the role of poorly liganded iron has been rather underappreciated in the past, and that in combination with peroxide and superoxide its activity underpins the behaviour of a great many physiological processes that degrade over time. Understanding these requires an integrative, systems-level approach that may lead to novel therapeutic targets.

Pharmacological treatment of sepsis

The incidence of sepsis, the combination of a systemic inflammatory response syndrome and documented infection, is as high as up to 95 cases per 100,000 people per year. The understanding of the pathophysiology of sepsis has much increased over the last 20 years. However, sepsis combined with shock is still associated with a high mortality rate varying from 35 to 55%. Causative treatment, source control and antibiotics started as soon as possible, are the cornerstone of therapy in combination with symptomatic treatment in the ICU. The pharmacological interventions, including fluid resuscitation, vasoactive drugs and adjunctive drugs such as steroids, activated protein C are discussed. The possible beneficial role of strict glucose control is also addressed. Since many drug intervention studies were negative, lessons should be learned from earlier experiences for future trials. Source control and level of intensive care should be eliminated as confounders.

[Microcirculation of intensive care patients. From the physiology to the bedside]

The microcirculation is unique in its anatomy and physiology and is a self-contained organ system within the human body. It is the site where gas exchange and nutrient supply takes place, but it is also the site which experiences pathological alterations during various shock states and therefore compromises the oxygen supply to tissues and organs. Systemic inflammation for example leads amongst others to increased heterogeneous blood flow, formation of interstitial edema, altered viscosity, leukocyte activation, disturbances in the coagulation system, and to a breakdown of the endothelial barrier function. These alterations inevitably lead to limitations of the oxygen supply to tissues. Without interruption of these pathomechanisms, the dysfunction of the microcirculation will consequently result in organ dysfunction. In this review article a short description of the microcirculatory physiology, the interaction between the macrocirculation and the microcirculation, as well as microcirculatory alterations generated by a systemic inflammatory response will be given. Finally, various therapy options will be described, which, experimentally, can lead to an improvement in microcirculatory dysfunction.

Potential roles for statins in critically ill patients

The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) are the most commonly prescribed agents for hypercholesterolemia and have revolutionized the management of hyperlipidemia and the area of cardiovascular risk reduction. However, recent data suggest that their effects go well beyond the lipid lowering seen with long-term use and may include acute antiinflammatory activity, anticoagulation, immunomodulation, as well as promotion of changes in smooth-muscle tone. Because of these data, promising research has begun into the use of these agents in various critical care areas such as the early phases of sepsis, bacteremia, and ischemic stroke. Recent data also show a decrease in cerebral vasospasm after subarachnoid hemorrhage, an area deficient in therapeutic options. More research is necessary to ascertain the true role of statins in the treatment of these various disorders. Nevertheless, the concept of a statin's role as being only a routine preventive therapy with benefits limited to patients undergoing extended treatment is rapidly becoming inaccurate.