Cohort study of serum total cholesterol and in-hospital incidence of infectious diseases

Statin treatment in stroke patient with low-density lipoprotein cholesterol levels below 70 mg/dL

BACKGROUND AND PURPOSE

The effectiveness of hyperlipidemia treatment in strokes secondary prevention has been established. However, whether pretreatment with statins could confer protective effects when a patient's baseline low-density lipoprotein cholesterol (LDL-C) level is <70 mg/dL remains uncertain. Additionally, the ability of statin treatment to reduce poststroke complications, mortality, and recurrence in this patient group is unclear.

METHODS AND RESULTS

In this retrospective observational study, we enrolled patients who had experienced an ischemic stroke with LDL-C levels <70 mg/dL. We analyzed the association of statin use with baseline characteristics, stroke severity, in-hospital complications, mortality rates, stroke recurrence rate, and mortality rate. Patients who used and patients who did not use statins were similar in terms of age and sex. Patients using statins had higher rates of diabetes mellitus, hypertension, prior stroke, and coronary artery disease but a lower incidence of atrial fibrillation. Stroke severity was less pronounced in those using statins. We also evaluated the relationship between in-hospital statin use and complications. We noted that in-hospital statin use was associated with lower rates of infection, hemorrhagic transformation, gastrointestinal hemorrhage, and mortality, as well as higher rates of positive functional outcomes. The 1-year recurrence rate was similar in both groups.

CONCLUSIONS

Statin use is associated with milder strokes and improved poststroke outcomes, even in patients with well-controlled LDL levels. Neurologists may consider prescribing statins for patients with ischemic stroke who do not overt hyperlipidemia. Further research into potential underlying mechanisms is warranted.

Surgical site infection following fasciotomy in patients with acute forearm compartment syndrome: a retrospective analysis of risk factors

PURPOSE

Fasciotomy, a standard therapy for acute forearm compartment syndrome (AFCS), can prevent serious complications, but there may be significant postoperative consequences. Surgical site infection (SSI) may cause fever, discomfort, and potentially fatal sepsis. This study aimed to identify risk factors for SSI in AFCS patients who had undergone fasciotomy.

MATERIALS AND METHODS

Patients with AFCS who had fasciotomies between November 2013 and January 2021 were recruited. We collected demographic information, comorbidities, and admission laboratory results. Analyses of continuous data were conducted using the t-test, the Mann-Whitney U test, and logistic regression analysis, while analyses of categorical data were conducted using the Chi-square and Fisher's exact tests.

RESULTS

Sixteen AFCS patients (13.9%) suffered infections that need further therapy. Using the logistic regression analysis, we identified that patients with a history of diabetes (p = 0.028, OR = 16.353, 95% CI (1.357, 197.001)), open fractures (p = 0.026, OR = 5.239, 95% CI (1.223, 22.438)), and a higher level of TC (p = 0.004, OR = 4.871, 95% CI (1.654-14.350)) were the best predictors of SSI, while ALB levels (p = 0.004, OR = 0.776, 95% CI (0.653-0.924)) were protective for SSI in AFCS patients.

CONCLUSIONS

Our results showed that open fractures, diabetes, and TC levels were relevent risk factors for SSI following fasciotomy in patients with AFCS, allowing us to personalize the risk assessment and apply early targeted interventions.

The bidirectional interaction of COVID-19 infections and lipoproteins

COVID-19 infections decrease total cholesterol, LDL-C, HDL-C, and apolipoprotein A-I, A-II, and B levels while triglyceride levels may be increased or inappropriately normal for the poor nutritional status. The degree of reduction in total cholesterol, LDL-C, HDL-C, and apolipoprotein A-I are predictive of mortality. With recovery lipid/lipoprotein levels return towards pre-infection levels and studies have even suggested an increased risk of dyslipidemia post-COVID-19 infection. The potential mechanisms for these changes in lipid and lipoprotein levels are discussed. Decreased HDL-C and apolipoprotein A-I levels measured many years prior to COVID-19 infections are associated with an increased risk of severe COVID-19 infections while LDL-C, apolipoprotein B, Lp (a), and triglyceride levels were not consistently associated with an increased risk. Finally, data suggest that omega-3-fatty acids and PCSK9 inhibitors may reduce the severity of COVID-19 infections. Thus, COVID-19 infections alter lipid/lipoprotein levels and HDL-C levels may affect the risk of developing COVID-19 infections.

The relationship of low-density lipoprotein cholesterol and all-cause or cardiovascular mortality in patients with type 2 diabetes: a retrospective study

Background

The optimal levels of low-density lipoprotein cholesterol (LDL-C) in patients with type 2 diabetes (T2D) are not currently clear. In this study, we determined the relationship between various mean LDL-C and all-cause or cardiovascular mortality risks in patients with T2D, stratifying by albumin level, age, sex, and antilipid medication use. We also evaluated the association of LDL-C standard deviation (LDL-C-SD) and all-cause and cardiovascular mortality by type of antilipid medication use.

Methods

A total of 46,675 T2D patients with a prescription for antidiabetic agents >6 months from outpatient visits (2003-2018) were linked to Taiwan's National Death Registry to identify all-cause and cardiovascular mortality. The Poisson assumption was used to estimate mortality rates, and the Cox proportional hazard regression model was used to assess the relative hazards of respective mortality in relation to mean LDL-C in patient cohorts by albumin level, age, sex, and antilipid use adjusting for medications, comorbidities, and laboratory results. We also determined the overall, and anti-lipid-specific mortality rates and relative hazards of all-cause and cardiovascular mortality associated with LDL-C-SD using the Poisson assumption and Cox proportional hazard regression model, respectively.

Results

All-cause and cardiovascular mortality rates were the lowest in T2D patients with a mean LDL-C > 90-103.59 mg/dL in the normal albumin group (≥ 3.5 g/dL). Compared to T2D patients with a mean LDL-C > 90-103.59 mg/dL, those with a mean LDL-C ≤ 77 mg/dL had an elevated risk of all-cause mortality in both the normal and lower albumin groups. T2D patients with a mean LDL-C ≤ 90 and > 103.59-119 mg/dL had relatively higher risk of cardiovascular mortality in the normal albumin group, but in the lower albumin group (<3.5 g/dL), any level of mean LDL-C ≤ 119 mg/dL was not significantly associated with cardiovascular mortality. Increased risks of all-cause and cardiovascular mortality were observed in patients with a mean LDL-C ≤ 77 mg/dL in both sexes and in all age groups except in those aged <50 years, a lower mean LDL-C was not associated with cardiovascular mortality. Similarly, patients with an LDL-C-SD <10^th and > 90^th percentiles were associated with significant risks of all-cause and cardiovascular mortality. In statin users, but not fibrate users, lower and higher levels of mean LDL-C and LDL-C-SD were both associated with elevated risks of all-cause and cardiovascular mortality.

Conclusions

The optimal level of LDL-C was found to be >90-103.59 mg/dL in T2D patients. Lower and higher levels of mean LDL-C and LDL-C-SD were associated with all-cause and cardiovascular mortality, revealing U-shaped associations. Further studies are necessary to validate the relationship between optimal LDL-C levels and all-cause and cardiovascular mortality in patients with diabetes.

Role of cholesterol, lipoproteins, and neutrophilic-lymphocytic ratio in patients with pneumonia

Background

Lipids play numerous functions in lung biology and pathophysiology of infection, in addition to their role in lipid transport, lipoproteins share in innate immunity that is the most important way for the host to defend against microbes. The NLR (neutrophil-lymphocytic ratio) is a good indicator of systemic inflammation and infection.

Objective

To evaluate the role of cholesterol, lipoproteins, and neutrophilic-lymphocytic ratio in the assessment of patients with pneumonia.

Patients and methods

This prospective case–control study included 52 subjects; they were categorized into 2 groups. Group A included 42 patients with pneumonia admitted to the Chest Department,Menoufia University, and group B included 10 healthy people during the period from May 2019 to December 2019. History taking, clinical examination, laboratory investigation in the form of CBC and lipid profile, and radiological investigation in the form of CXR and CT chest if needed were done to all subjects of the study.

Results

The mean cholesterol level in group A was 149.76 ± 42.79 which was statistically significantly lower as compared with group B (165.90 ± 45.50) (p = 0.039). The mean HDL level in group A was 43.16 ± 6.32 which was statistically significantly lower as compared with group B (50.51 ± 9.60) (p = 0.026). No statistically significant difference was found in the triglyceride level, LDL level and VLDL between the subjects in the two studied groups (p = 0.479, 0.792, and 0.606), respectively, but all levels were still within normal levels. Mean NLR in group A was 7.04 ± 7.98 which was statistically significantly higher as compared with group B (3.04 ± 1.6) (p = 0.004). Roc curve of neutrophil–lymphocyte ratio shows that the cutoff point is 1.94 and the N/L ratio had area under curve of 78% with 79.6% sensitivity and 67.8% specificity.

Conclusion

Serum cholesterol and high-density lipoprotein levels significantly decreased in patients with pneumonia when compared to the control group but were still within normal range. Lipid profile is affected by different variables like smoking index, body mass index, and sex. The neutrophil–lymphocyte at cutoff point is 1.94, and N/L ratio had area under curve of 78% with 79.6% sensitivity and 67.8% specificity.

Trial registration

TCTR, TCTR20220524001. Registered on 24 May 2022, retrospectively registered.

Relationship between maternal and/or newborn cholesterol levels and neonatal septicemia: protocol for a Ugandan cohort of mother-newborn pairs

Background

Many aspects of microbial dissemination appear to vary with host cholesterol levels. Since neonatal septicemia remains a leading cause of newborn admissions and mortality in resource-limited settings, the contribution of abnormal cholesterol levels in maternal and/or newborn blood to the risk of neonatal septicemia and outcome requires elucidation. We aim to determine a relationship between maternal serum and neonatal cord blood cholesterol levels and neonatal septicemia.

Methods

This will be a mother-newborn pair cohort study. Approximately 353 pregnant women who are eligible and consent to participate in the study will have blood drawn for a lipid profile. Upon delivery, we will analyse the cord blood cholesterol of their newborns and follow them for 28 days to determine whether the infants develop clinical signs and symptoms suggestive of neonatal septicemia. Relative risk will be used to determine the association between cholesterol and newborn septicemia. Poisson regression will be used to estimate the relative risk (with 95% confidence intervals) of developing septicemia.

Discussion

Findings from our study will contribute evidence to support the inclusion of lipid profile screening for pregnant women and newborns. Our study will determine whether newborns with abnormal cholesterol or those born to mothers with abnormal cholesterol will require rigorous follow-up in neonatal clinics.

The role of PCSK9 in inflammation, immunity, and autoimmune diseases

INTRODUCTION

Statins have pleiotropic effects, being both anti-inflammatory and immunomodulatory. Proprotein convertase subtilisin kexin 9 (PCSK9) targets the low-density lipoprotein receptor (LDLR), which increases LDL levels due to the lower expression of LDLR.

AREAS COVERED

Inhibition of PCSK9 by the use of antibodies represents a novel principle to lower LDL levels. LDL may have other properties than being a cholesterol carrier but is well established as a risk factor for cardiovascular disease and atherosclerosis. In atherosclerosis, the plaques are characterized by activated T cells and dendritic cells (DCs), dead cells, and OxLDL. The latter may be an important cause of the inflammation typical of atherosclerosis, by promoting a proinflammatory immune activation. This is inhibited by PCSK9 inhibition, and an anti-inflammatory type of immune activation is induced. OxLDL is raised in systemic lupus erythematosus (SLE), where both CVD and atherosclerosis are much increased compared to the general population. PCSK9 is reported to be associated with disease activity and complications in SLE. Also in other rheumatoid arthritis, PCSK9 may play a role.

EXPERT OPINION

PCSK9 has pleiotropic effects, being implicated in inflammation and immunity. Inhibition of PCSK9 is therefore interesting to study further as a potential therapy against inflammation and autoimmunity.

HDL in COVID-19 Patients: Evidence from an Italian Cross-Sectional Study

A number of studies have highlighted important alterations of the lipid profile in COVID-19 patients. Besides the well-known atheroprotective function, HDL displays anti-inflammatory, anti-oxidative, and anti-infectious properties. The aim of this retrospective study was to assess the HDL anti-inflammatory and antioxidant features, by evaluation of HDL-associated Serum amyloid A (SAA) enrichment and HDL-paraoxonase 1 (PON-1) activity, in a cohort of COVID-19 patients hospitalized at the Cardiorespiratory COVID-19 Unit of Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico of Milan. COVID-19 patients reached very low levels of HDL-c (mean ± SD: 27.1 ± 9.7 mg/dL) with a marked rise in TG (mean ± SD: 165.9 ± 62.5 mg/dL). Compared to matched-controls, SAA levels were significantly raised in COVID-19 patients at admission. There were no significant differences in the SAA amount between 83 alive and 22 dead patients for all-cause in-hospital mortality. Similar findings were reached in the case of PON-1 activity, with no differences between alive and dead patients for all-cause in-hospital mortality. In conclusion, although not related to the prediction of in-hospital mortality, reduction in HDL-c and the enrichment of SAA in HDL are a mirror of SARS-CoV-2 positivity even at the very early stages of the infection.

Decreased Low-Density Lipoprotein Cholesterol Level Indicates Poor Prognosis of Severe and Critical COVID-19 Patients: A Retrospective, Single-Center Study

Coronavirus disease 2019 (COVID-19) has become a global public health crisis. Reduced low-density lipoprotein cholesterol (LDL-C) levels were observed in COVID-19 patients. The present study aimed to explore the relationship between LDL-C levels and the prognosis of severe and critical COVID-19 patients. A total of 211 severe and critical COVID-19 patients were enrolled and divided into four groups according to the LDL-C levels, including 53 patients in Group A (LDL-C ≥ 2.71 mmol/L), 53 patients in Group B (2.28 ≤ LDL-C < 2.71 mmol/L), 53 patients in Group C (1.83 ≤ LDL-C < 2.28 mmol/L) and 52 patients in Group D (LDL-C < 1.83 mmol/L). LDL-C levels were lower in critically ill patients than in severe patients. The main symptoms before admission, characteristics on admission and comorbidities of enrolled patients did not differ among the four groups. Compared with patients with high LDL-C levels, patients with low LDL-C levels were more likely to have immune and inflammation dysfunction, renal dysfunction, liver dysfunction and cardiac dysfunction on admission. The proportions of patients with shock and acute cardiac injury, of those admitted to intensive care unit (ICU) and of those treated with mechanical ventilation were inversely related to LDL-C level. The mortality of COVID-19 patients increased with LDL-C reduction. Serum LDL-C levels of COVID-19 patients was negatively correlated with CRP level, but positively correlated with lymphocyte count, as shown by Pearson correlation analysis. Proportional hazard models showed that low LDL-C levels were associated with increased risk of hospitalization death, cardiac injury and admission to the ICU. Taken together, these results suggest that decreased LDL-C levels indicate poor prognosis of severe and critical COVID-19 patients.

Immunologic Aspects of Dyslipidemia: a Critical Regulator of Adaptive Immunity and Immune Disorders

Dyslipidemia is a major cause of cardiovascular diseases which represent a leading cause of death in humans. Diverse immune cells are known to be involved in the pathogenesis of cardiovascular diseases such as atherosclerosis. Conversely, dyslipidemia is known to be tightly associated with immune disorders in humans, as evidenced by a higher incidence of atherosclerosis in patients with autoimmune diseases including psoriasis, rheumatoid arthritis, and systemic lupus erythematosus. Given that the dyslipidemia-related autoimmune diseases are caused by autoreactive T cells and B cells, dyslipidemia seems to directly or indirectly regulate the adaptive immunity. Indeed, accumulating evidence has unveiled that proatherogenic factors can impact the differentiation and function of CD4⁺ T cells, CD8⁺ T cells, and B cells. This review discusses an updated overview on the regulation of adaptive immunity by dyslipidemia and proposes a potential therapeutic strategy for immune disorders by targeting lipid metabolism.

Cytokine release syndrome in COVID-19: a major mechanism of morbidity and mortality

The coronavirus disease 2019 (COVID-19) triggered by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) erupted in Hubei Province of China in December 2019 and has become a pandemic. Severe COVID-19 patients who suffer from acute respiratory distress syndrome (ARDS) and multi-organ dysfunction have high mortality. Several studies have shown that this is closely related to the cytokine release syndrome (CRS), often loosely referred to as cytokine storm. IL-6 is one of the key factors and its level is positively correlated with the severity of the disease. The molecular mechanisms for CRS in COVID-19 are related to the effects of the S-protein and N-protein of the virus and its ability to trigger NF-κB activation by disabling the inhibitory component IκB. This leads to activation of immune cells and the secretion of proinflammatory cytokines such as IL-6 and TNF-α. Other mechanisms related to IL-6 include its interaction with GM-CSF and interferon responses. The pivotal role of IL-6 makes it a target for therapeutic agents and studies on tocilizumab are already ongoing. Other possible targets of treating CRS in COVID-19 include IL-1β and TNF-α. Recently, reports of a CRS like illness called multisystem inflammatory syndrome in children (MIS-C) in children have surfaced, with a variable presentation which in some cases resembles Kawasaki disease. It is likely that the immunological derangement and cytokine release occurring in COVID-19 cases is variable, or on a spectrum, that can potentially be governed by genetic factors. Currently, there are no approved biological modulators for the treatment of COVID-19, but the urgency of the pandemic has led to numerous clinical trials worldwide. Ultimately, there is great promise that an anti-inflammatory modulator targeting a cytokine storm effect may prove to be very beneficial in reducing morbidity and mortality in COVID-19 patients.

Cholesterol, lipoproteins, and COVID-19: Basic concepts and clinical applications

Cholesterol is being recognized as a molecule involved in regulating the entry of the SARS-CoV-2 virus into the host cell. However, the data about the possible role of cholesterol carrying lipoproteins and their receptors in relation to infection are scarce and the connection of lipid-associated pathologies with COVID-19 disease is in its infancy. Herein we provide an overview of lipids and lipid metabolism in relation to COVID-19, with special attention on different forms of cholesterol. Cholesterol enriched lipid rafts represent a platform for viruses to enter the host cell by endocytosis. Generally, higher membrane cholesterol coincides with higher efficiency of COVID-19 entry. Inversely, patients with COVID-19 show lowered levels of blood cholesterol, high-density lipoproteins (HDL) and low-density lipoproteins. The modulated efficiency of viral entry can be explained by availability of SR-B1 receptor. HDL seems to have a variety of roles, from being itself a scavenger for viruses, an immune modulator and mediator of viral entry. Due to inverse roles of membrane cholesterol and lipoprotein cholesterol in COVID-19 infected patients, treatment of these patients with cholesterol lowering statins needs more attention. In conclusion, cholesterol and lipoproteins are potential markers for monitoring the viral infection status, while the lipid metabolic pathways and the composition of membranes could be targeted to selectively inhibit the life cycle of the virus as a basis for antiviral therapy.

Association between serum lipids, polyunsaturated fatty acids, and prognosis in maintenance hemodialysis patients

INTRODUCTION

Risks of mortality and cardiovascular disease (CVD) are significantly higher in hemodialysis (HD) patients than in the general population, where dyslipidemia is an established risk factor for CVD and mortality. There is no clear conclusion, however, whether dyslipidemia is a significant risk factor for CVD and mortality in HD patients. Similarly, the association between the polyunsaturated fatty acids (PUFAs) and the mortality is not clear in HD patients.

METHODS

We retrospectively investigated mortality and CVD events in 420 HD patients. We classified patients into high- and low-lipid groups depending on their lipid levels. Survival rates were calculated using the Kaplan-Meier analysis and evaluated by the log-rank test. The risk estimates were computed using a multivariate Cox proportional hazard analysis.

FINDINGS

During their follow-up (June 2011 to June 2016), 151 patients died (37 of CVD), and 112 patients experienced new CVD events. On Kaplan-Meier analysis, the number of all-cause deaths and CVD events were significantly higher in the low HDL-cholesterol group (P < 0.01, log-rank test). Similarly, the number of all-cause deaths was significantly higher in the high eicosapentaenoic acid/arachidonic acid ratio group (P < 0.01, log-rank test). Multivariate Cox proportional analysis showed that HDL-cholesterol was a significant prognostic indicator for new onset of CVD events (low: 0, high: 1, hazard ratio 0.66, 95% confidence interval 0.44-0.97; P = 0.04).

DISCUSSION

In HD patients, LDL-cholesterol and non-HDL-cholesterol levels are not associated with mortality or CVD events. The HDL-cholesterol level, however, is an independent predictor of new CVD events even in HD patients.

Pros and cons for use of statins in people with coronavirus disease-19 (COVID-19)

BACKGROUND AND AIMS

Morbidity and mortality from coronavirus disease 2019 (COVID-19) is higher among people with diabetes mellitus (DM), hypertension, and cardiovascular disease (CVD). Statins are used in the majority of people with DM and CVD. This mini-review discusses the current understanding of benefit-risk ratio of use of statins in COVID-19.

METHODS

We searched PubMed database using specific keywords related to our aims till June 12, 2020. Full text of relevant articles published in English language were retrieved and reviewed.

RESULTS

Statins, with their immunomodulatory, anti-inflammatory, anti-thrombotic, and anti-oxidant properties, have the potential to reduce severity of lung injury in, and mortality from, severe acute respiratory syndrome-coronavirus 2 (SARS-CoV2) infections. Statin-induced upregulation of angiotensin-converting enzyme-2 (ACE2) has the potential to reduce lung injury from excess angiotensin II. By disrupting lipid rafts, statins have the potential to reduce viral entry into cells. However, benefit-risk ratio of its complex interaction with MYD88 gene expression on outcomes in COVID-19, and the putative role of low serum LDL cholesterol in increasing severity of SARS-CoV2 infection need further clarification.

CONCLUSIONS

People with COVID-19, who are already on statins for an underlying co-morbid condition, should continue on it unless there are specific contraindications. De-novo use of statins in people with COVID-19 with no underlying co-morbidity might be beneficial but awaits substantiation in clinical trials; till that time, de novo use of statins in COVID 19 should be limited to a clinical trial setting.

Cholesterol: A new game player accelerating vasculopathy caused by SARS-CoV-2?

The pandemic of coronavirus disease (COVID-19) has become a global threat to public health. Functional impairments in multiple organs have been reported in COVID-19, including lungs, heart, kidney, liver, brain, and vascular system. Patients with metabolic-associated preconditions, such as hypertension, obesity, and diabetes, are susceptible to experiencing severe symptoms. The recent emerging evidence of coagulation disorders in COVID-19 suggests that vasculopathy appears to be an independent risk factor promoting disease severity and mortality of affected patients. We recently found that the decreased levels of low-density lipoprotein cholesterols (LDL-c) correlate with disease severity in COVID-19 patients, indicating pathological interactions between dyslipidemia and vasculopothy in patients with COVID-19. However, this clinical manifestation has been unintentionally underestimated by physicians and scientific communities. As metabolic-associated morbidities are generally accompanied with endothelial cell (EC) dysfunctions, these pre-existing conditions may make ECs more vulnerable to SARS-CoV-2 attack. In this mini-review, we summarize the metabolic and vascular manifestations of COVID-19 with an emphasis on the association between changes in LDL-c levels and the development of severe symptoms as well as the pathophysiologic mechanisms underlying the synergistic effect of LDL-c and SARS-CoV-2 on EC injuries and vasculopathy.

Serum lipid profiles of young Japanese women with iron deficiency without anemia

PURPOSE

We aimed to evaluate the association between iron deficiency without anemia (IDNA) and serum lipid profiles in young women of around 20 years of age.

METHODS

This study included non-anemic (hemoglobin ≥ 12 g/dL) female volunteers aged 18 to 22 years who were not taking mineral/vitamin supplements and living in the metropolitan area of Tokyo, Japan. These volunteers were classified into two groups based on their sFer (serum ferritin) levels: normal group (sFer ≥ 20 ng/mL, n = 36) and IDNA group (sFer < 20 ng/mL, n = 29). Venous blood samples were obtained from the antecubital veins of these volunteers after 10-12-h fasting to measure the hematological and biochemical parameters, including lipid levels and iron status. The results of each group were compared using Student's t-test or the Mann-Whitney U test (for inhomogeneous variance).

RESULTS

The serum cholesterol levels varied depending on the iron status in the women. Serum high-density lipoprotein cholesterol (HDL-C) levels in the IDNA group were significantly higher (P = 0.006) than that in the normal group. However, the levels of total cholesterol (T-CHO), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C) were not significantly different between the groups. Serum LDL-C levels were positively and significantly correlated with sFer levels in the IDNA group (Kendall's rank correlation 0.264, P = 0.044), but not in the normal group. The sFer level was not correlated with serum HDL-C in both groups. The reason for the high serum HDL-C levels in young women with IDNA is not yet clear. Compared to the normal group, the frequency of eating bread containing bran was significantly higher (P = 0.031) and that for yogurt was significantly lower (P = 0.040) in the IDNA group. The proportion of the women who were susceptible to infection, which was measured using the Cornell Medical Index, was significantly higher in the IDNA group than in the normal group. Among those susceptible to infection, the serum HDL-C level of the volunteers in the IDNA group was significantly higher than that of the volunteers in the normal group (P = 0.024).

CONCLUSIONS

Our findings suggest that lipid parameters may be associated with IDNA and susceptibility to infection. Further research is needed to elucidate the mechanisms underlying the changes in the serum cholesterol levels in individuals with IDNA and the clinical significance of these findings.

Association between hyperlipidemia and mortality after incident acute myocardial infarction or acute decompensated heart failure: a propensity score matched cohort study and a meta-analysis

OBJECTIVE

To examine the effect of HLP, defined as having a pre-existing or a new in-hospital diagnosis based on low density lipoprotein cholesterol (LDL-C) level ≥100 mg/dL during index hospitalisation or within the preceding 6 months, on all-cause mortality after hospitalisation for acute myocardial infarction (AMI) or acute decompensated heart failure (ADHF) and to determine whether HLP modifies mortality associations of other competing comorbidities. A systematic review and meta-analysis to place the current findings in the context of published literature.

DESIGN

Retrospective study, 1:1 propensity-score matching cohorts; a meta-analysis.

SETTING

Large academic centre, 1996-2015.

PARTICIPANTS

Hospitalised patients with AMI or ADHF.

MAIN OUTCOMES AND MEASURES

All-cause mortality and meta-analysis of relative risks (RR).

RESULTS

Unmatched cohorts: 13 680 patients with AMI (age (mean) 68.5 ± (SD) 13.7 years; 7894 (58%) with HLP) and 9717 patients with ADHF (age, 73.1±13.7 years; 3668 (38%) with HLP). In matched cohorts, the mortality was lower in AMI patients (n=4348 pairs) with HLP versus no HLP, 5.9 versus 8.6/100 person-years of follow-up, respectively (HR 0.76, 95% CI 0.72 to 0.80). A similar mortality reduction occurred in matched ADHF patients (n=2879 pairs) with or without HLP (12.4 vs 16.3 deaths/100 person-years; HR 0.80, 95% CI 0.75 to 0.86). HRs showed modest reductions when HLP occurred concurrently with other comorbidities. Meta-analyses of nine observational studies showed that HLP was associated with a lower mortality at ≥2 years after incident AMI or ADHF (AMI: RR 0.72, 95% CI 0.69 to 0.76; heart failure (HF): RR 0.67, 95% CI 0.55 to 0.81).

CONCLUSIONS

Among matched AMI and ADHF cohorts, concurrent HLP, compared with no HLP, was associated with a lower mortality and attenuation of mortality associations with other competing comorbidities. These findings were supported by a systematic review and meta-analysis.

Peritonitis Affects the Relationship Between Low-Density Lipoprotein Cholesterol and Cardiovascular Events in Peritoneal Dialysis Patients

BACKGROUND

In peritoneal dialysis (PD), the relationship among low-density lipoprotein cholesterol (LDL-C), peritonitis, and cardiovascular (CV) disease has not been clarified. This study was performed to explore their associations in a large PD cohort.

METHODS

This retrospective cohort study included incident patients who received PD catheter insertion in our centre. The primary outcome was the first CV event (nonfatal myocardial infarction, CV death, non-haemorrhagic stroke, or any arterial revascularization procedure). Secondary outcomes were the occurrence of peritonitis, CV mortality, and all-cause mortality.

RESULTS

This study included 1294 patients, whose mean age was 48.1 years. After adjustment for confounders in negative binomial regression models, lower LDL-C quartiles were independently associated with a higher risk of peritonitis, compared with the highest quartile. The multivariate competing risk model showed no significant association between baseline LDL-C and the first CV event in the overall population. However, stratified analysis showed that each 1 mmol/L increase in LDL-C was independently associated with a 21% (subdistribution hazard ratio: 1.21, 95% confidence interval: 1.06-1.39) increased risk of the first CV event among peritonitis-free patients, and with a 20% (subdistribution hazard ratio: 0.80, 95% confidence interval: 0.65-0.99) decreased risk among patients with peritonitis. Moderating-effect analysis showed that the presence of peritonitis significantly influenced the relationships between LDL-C and CV events (P < 0.001). Similar results were also observed in the relationship between LDL-C and mortality.

CONCLUSIONS

PD patients with lower baseline LDL-C had a higher risk of peritonitis. The effect of LDL-C on CV events and mortality was different by the presence of peritonitis events.

Hospital-Level Variations in Rates of Inpatient Urinary Tract Infections in Stroke

Background and purpose: Urinary tract infection (UTI) is one of the most common complications following stroke and has prognostic significance. UTI rates have been shown to vary between hospitals, but it is unclear whether this is due to case-mix differences or heterogeneities in care among hospitals.

Methods: A prospective multi-center cohort study of acute stroke patients admitted to eight National Health Service (NHS) acute hospital trusts within the Anglia Stroke & Heart Clinical Network between 2009 and 2011 was conducted. We modeled the association between hospital (as a fixed-effect) and inpatient UTI using a multivariable logistic regression model, adjusting for established patient-level risk factors. We graphically and descriptively analyzed heterogeneities in hospital-level characteristics.

Results: We included 2,241 stroke admissions in our analysis; 171 (7.6%) acquired UTI as an inpatient. UTI rates varied significantly between the eight hospitals, ranging from 3 to 11%. The hospital that had the lowest odds of UTI [odds ratio (OR) = 0.50 (95% confidence interval (CI) 0.22–.11)] in adjusted analysis, had the highest number of junior doctors and occupational therapists per five beds of all hospitals. The hospital with the highest adjusted UTI rate [OR=2.69 (1.56–4.64)] was tertiary, the largest and had the highest volume of stroke patients, lowest number of stroke unit beds per 100 admissions, and the highest number of hospital beds per CT scanner.

Conclusions: There is hospital-level variation in post-stroke UTI. Our results suggest the potential influence of service characteristics independently of patient-level factors which may be amenable to be addressed to improve the ultimate stroke outcome.

Lipid levels are inversely associated with infectious and all-cause mortality: international MONDO study results

Cardiovascular (CV) events are increased 36-fold in patients with end-stage renal disease. However, randomized controlled trials to lower LDL cholesterol (LDL-C) and serum total cholesterol (TC) have not shown significant mortality improvements. An inverse association of TC and LDL-C with all-cause and CV mortality has been observed in patients on chronic dialysis. Lipoproteins also may protect against infectious diseases. We used data from 37,250 patients in the international Monitoring Dialysis Outcomes (MONDO) database to evaluate the association between lipids and infection-related or CV mortality. The study began on the first day of lipid measurement and continued for up to 4 years. We applied Cox proportional models with time-varying covariates to study associations of LDL-C, HDL cholesterol (HDL-C), and triglycerides (TGs) with all-cause, CV, infectious, and other causes of death. Overall, 6,147 patients died (19.2% from CV, 13.2% from infection, and 67.6% from other causes). After multivariable adjustment, higher LDL-C, HDL-C, and TGs were independently associated with lower all-cause death risk. Neither LDL-C nor TGs were associated with CV death, and HDL-C was associated with lower CV risk. Higher LDL-C and HDL-C were associated with a lower risk of death from infection or other non-CV causes. LDL-C was associated with reduced all-cause and infectious, but not CV mortality, which resulted in the inverse association with all-cause mortality.

Differential Effects of Statins on Inflammatory Interleukin-8 and Antimicrobial Peptide Human Β-Defensin 2 Responses in Salmonella-Infected Intestinal Epithelial Cells

Alternative therapies are needed to reduce the use of antibiotics and incidence of drug-resistant Salmonellosis. Previous studies have revealed important roles of statins in regulating innate immunity. Therefore, we investigated the effects of statins on innate immunity in Salmonella-infected intestinal epithelial cells (IECs), which are involved in mucosal innate immunity. SW480 cells and Akt siRNA- or vitamin D receptor (VDR) siRNA-transfected SW480 cells were infected by wild-type S. Typhimurium strain SL1344 in the presence or absence of statins. The mRNA or protein expression was analyzed by real-time quantitative PCR or western blot analysis, respectively. Simvastatin or fluvastatin caused IL-8 (interleukin-8) suppression, but increased hBD-2 mRNA expression in Salmonella-infected SW480 cells. Both statins enhanced phosphorylated Akt and VDR expressions. Akt or VDR knockdown by siRNA counteracted the suppressive effect of simvastatin on IL-8 expression, whereas VDR knockdown diminished the enhanced hBD-2 expression in Salmonella-infected SW480 cells. Therefore, we observed differential regulation of statins on inflammatory IL-8 and anti-microbial hBD-2 expressions in Salmonella-infected IECs via PI3K/Akt signaling and VDR protein expression, respectively. The enhanced activity of antimicrobial peptides by statins in Salmonella-infected IECs could protect the host against infection, and modulation of pro-inflammatory responses could prevent the detrimental effects of overwhelming inflammation in the host.

Effect on non-vascular outcomes of lowering LDL cholesterol in patients with chronic kidney disease: results from the Study of Heart and Renal Protection

Background

Reducing LDL cholesterol (LDL-C) with statin-based therapy reduces the risk of major atherosclerotic events among patients with chronic kidney disease (CKD), with no evidence of an excess risk of cancer or death from any non-vascular cause. However, non-randomized data have suggested that statin therapy may have effects (both adverse and beneficial) on particular non-vascular conditions that do not cause death.

Methods

The Study of Heart and Renal Protection (SHARP) randomized patients with CKD to simvastatin 20 mg plus ezetimibe 10 mg (simvastatin/ezetimibe) daily versus matching placebo. Participants were followed up at least 6 monthly and all post-randomization serious adverse events (SAEs) were recorded. This supplementary analysis reports the effects of treatment on non-vascular SAEs, overall, by system of disease, by baseline characteristics, and by duration of follow-up.

Results

During a median of 4.9 years follow-up, similar numbers of participants in the two groups experienced at least one non-vascular SAE (3551 [76.4%] simvastatin/ezetimibe vs 3537 [76.6%] placebo; risk ratio [RR] 0.99, 95% confidence interval [CI] 0.95–1.04). There was no good evidence of any significant effect of simvastatin/ezetimibe on SAEs attributed to any particular nonvascular disease system (of 43 comparisons, only 3 yielded an uncorrected p value < 0.05, of which the smallest was p = 0.02). The relative risk of any nonvascular SAE did not vary significantly among particular prognostic subgroups or by duration of follow-up.

Conclusions

In the SHARP trial, allocation to simvastatin/ezetimibe combination therapy was not associated with any significant non-vascular hazard.

Trials registration

SHARP was retrospectively registered after the first participant was enrolled in 2003 at ISRCTN (ISRCTN54137607 on 31 January 2005: http://www.isrctn.com/ISRCTN54137607) and ClinicalTrials.gov (NCT00125593 on 29 July 2005: https://clinicaltrials.gov/ct2/show/NCT00125593).

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-017-0545-2) contains supplementary material, which is available to authorized users.

Lack of an association or an inverse association between low-density-lipoprotein cholesterol and mortality in the elderly: a systematic review

OBJECTIVE

It is well known that total cholesterol becomes less of a risk factor or not at all for all-cause and cardiovascular (CV) mortality with increasing age, but as little is known as to whether low-density lipoprotein cholesterol (LDL-C), one component of total cholesterol, is associated with mortality in the elderly, we decided to investigate this issue.

SETTING, PARTICIPANTS AND OUTCOME MEASURES

We sought PubMed for cohort studies, where LDL-C had been investigated as a risk factor for all-cause and/or CV mortality in individuals ≥60 years from the general population.

RESULTS

We identified 19 cohort studies including 30 cohorts with a total of 68 094 elderly people, where all-cause mortality was recorded in 28 cohorts and CV mortality in 9 cohorts. Inverse association between all-cause mortality and LDL-C was seen in 16 cohorts (in 14 with statistical significance) representing 92% of the number of participants, where this association was recorded. In the rest, no association was found. In two cohorts, CV mortality was highest in the lowest LDL-C quartile and with statistical significance; in seven cohorts, no association was found.

CONCLUSIONS

High LDL-C is inversely associated with mortality in most people over 60 years. This finding is inconsistent with the cholesterol hypothesis (ie, that cholesterol, particularly LDL-C, is inherently atherogenic). Since elderly people with high LDL-C live as long or longer than those with low LDL-C, our analysis provides reason to question the validity of the cholesterol hypothesis. Moreover, our study provides the rationale for a re-evaluation of guidelines recommending pharmacological reduction of LDL-C in the elderly as a component of cardiovascular disease prevention strategies.

Serum Total Cholesterol Levels Would Predict Nosocomial Infections After Gastrointestinal Surgery

It has been suggested that total cholesterol levels and the use of statin medications are associated with the incidence of complications after gastrointestinal surgery. The aim of this study was to determine if preoperative total cholesterol levels are associated with a higher risk of postoperative infections and mortality. A total of 2211 patients undergoing general surgical procedures between December 2006 and November 2008 at Iizuka Hospital and between January 2010 and March 2012 at Jichi Medical University Hospital were reviewed. Multiple logistic regression models were used to evaluate serum total cholesterol and other variables as predictors of postoperative nosocomial infections. Serum total cholesterol concentrations lower than 160 mg/dl were associated with an increased incidence of superficial and deep incisional surgical site infections. Serum total cholesterol levels showed a reverse J-shaped relationship with the development of organ space surgical site infection and pneumonia. There was no discernible effect of serum cholesterol levels on the postoperative mortality observed in this cohort of patients. Decreased serum albumin was one of the strongest risk factors for the development of nosocomial infection after surgery. Postoperative pneumonia was not observed in patients taking statin medications whose cholesterol levels were <200 mg/dl. Serum total cholesterol may be a valid predictor of surgical outcome. Preoperative statin use may affect the development of postoperative pneumonia in patients with total cholesterol levels below 200 mg/dl.

Lower Low-Density Lipoprotein Cholesterol Levels Are Associated with Severe Dengue Outcome

Dengue virus (DENV) is a flavivirus of worldwide importance, with approximately 4 billion people across 128 countries at risk of infection, and up to 390 million infections and 96 million clinically apparent cases estimated annually. Previous in vitro studies have shown that lipids and lipoproteins play a role in modifying virus infectivity. However, the relationship between development of severe dengue and total cholesterol, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C), respectively, is unclear. We analyzed data from 789 laboratory-confirmed dengue cases and 447 other febrile illnesses (OFI) in a prospective pediatric hospital-based study in Managua, Nicaragua between August 2005 and January 2013, using three different classifications of dengue severity: World Health Organization (WHO) 1997, WHO 2009, and standardized intervention categories. Total serum cholesterol and LDL-C levels decreased over the course of illness and were generally lower with increasing dengue severity, regardless of classification scheme. Greater decreases in LDL-C than HDL-C were observed among dengue-positive patients compared to patients with OFI and among severe dengue compared to mild dengue cases. Furthermore, daily cholesterol levels declined with daily albumin blood levels. To examine the effect of cholesterol at presentation on subsequent risk of development of severe dengue, relative risks and 95% confidence intervals were calculated using multivariable modified Poisson models. We found that lower total serum cholesterol and LDL-C levels at presentation were associated with subsequent risk of developing dengue hemorrhagic fever/dengue shock syndrome using the WHO 1997 dengue severity classification, and thus that the reduction in LDL-C is likely driving the decreases observed in total serum cholesterol levels among dengue-positive patients. Our results suggest that cholesterol blood levels are important correlates of dengue pathophysiology and should be explored as part of a prognostic biomarker panel for severe dengue.

Dengue is a viral infection of worldwide importance with up to 96 million cases annually. Cholesterol, a type of lipid, may play a role in dengue virus infectivity and severity, but changes in cholesterol levels over the course of illness are not well-understood. To investigate the relationship between development of severe dengue and total cholesterol, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C), we analyzed data from a prospective hospital-based study of pediatric dengue in Managua, Nicaragua (August 2005–January 2013). Because different classifications of dengue severity are used, we performed analyses using three different classifications. Cholesterol decreased over the course of illness and differed across disease outcome, regardless of classification scheme. Greater decreases in LDL-C than HDL-C were observed among dengue-positive patients versus patients with other febrile illnesses and among severe versus mild dengue cases. In multivariate models, lower total serum cholesterol and LDL-C levels at presentation were associated with subsequent risk of developing dengue hemorrhagic fever/dengue shock syndrome (World Health Organization 1997 classification). Our results suggest that reduction in LDL-C is likely driving decreases observed in total serum cholesterol levels among dengue-positive patients and should be explored as part of a prognostic biomarker panel for severe dengue.

Low preoperative cholesterol level is a risk factor of sepsis and poor clinical outcome in patients undergoing cardiac surgery with cardiopulmonary bypass

OBJECTIVES

Systemic inflammatory response syndrome and sepsis frequently occur after cardiac surgery with cardiopulmonary bypass. The aim of the present study was to investigate whether preoperative cholesterol levels can predict sepsis onset and postoperative complications in patients undergoing cardiac surgery with cardiopulmonary bypass.

DESIGN

Prospective observational study.

SETTING

Surgical ICU of a French university hospital.

PATIENTS

Two hundred and seventeen consecutive patients older than 18 years admitted for planned cardiac surgery with cardiopulmonary bypass.

INTERVENTIONS

Measurements of plasma blood lipids and inflammation markers before anesthesia induction (baseline), at cardiopulmonary bypass start, at cardiopulmonary bypass end, and 3 and 24 hours after cardiac surgery. Outcomes were compared in systemic inflammatory response syndrome patients with sepsis (n = 15), systemic inflammatory response syndrome patients without sepsis (n = 95), and non-systemic inflammatory response syndrome patients (n = 107).

MEASUREMENTS AND MAIN RESULTS

A gradual decrease in plasma cholesterol concentration occurred during surgery with cardiopulmonary bypass but was no longer present after correction for hemodilution. Corrected cholesterol levels were significantly lower at baseline in sepsis patients than in other subgroups, and it remained lower in the sepsis group during and after cardiopulmonary bypass. With regard to sepsis, the discriminatory power of baseline cholesterol was fairly good as indicated by receiver operating characteristic curve analysis (area under the curve, 0.78; 95% CI, 0.72-0.84). The frequency of sepsis progressively decreased with increasing baseline cholesterol level quintiles (18.6% and 0% in the bottom and top quintiles, respectively, p = 0.005). In multivariate analysis, baseline cholesterol levels and cardiopulmonary bypass duration were significant and independent determinants of the 3-hour postcardiopulmonary bypass increase in concentrations of procalcitonin and interleukin-8, but not of interleukin-6.

CONCLUSIONS

Low cholesterol levels before elective cardiac surgery with cardiopulmonary bypass may be a simple biomarker for the early identification of patients with a high risk of sepsis.

The effect of statin therapy on the incidence of infections: a retrospective cohort analysis

BACKGROUND

Statins have been postulated to prevent infection through immunomodulatory effects.

OBJECTIVES

To compare the incidence of infections in statin users to that in nonusers within the same health care system.

METHODS

This was a retrospective cohort study of patients enrolled as Tricare Prime or Plus in the San Antonio military multimarket. Statin users were patients who received a statin for at least 3 months between October 1, 2004 and September 30, 2005. Nonusers were patients who did not receive a statin within the study period (October 1, 2003-September 30, 2009). Inpatient and outpatient International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) codes were used to determine the incidence of infections during the follow-up period (October 1, 2005-September 30, 2009) via multivariable regression analysis and time to infection via Cox regression analysis.

RESULTS

Of 45,247 patients who met the study criteria, 12,981 (29%) were statin users and 32,266 were nonusers. After adjustments for age, gender, Charlson Comorbidity Score, tobacco use, alcohol abuse/dependence, health care utilization and use of specific medication classes, statin use was associated with an increased incidence of common infections (odds ratio [OR]: 1.13; 95% confidence interval [CI]: 1.06-1.19) but not influenza or fungal infections (OR: 1.06, 95% CI: 0.80-1.39; OR: 0.97; 95% CI: 0.91-1.04, respectively). Time-to-first infection was similar in statin users and nonusers in all infection categories examined.

CONCLUSIONS

Statin use was associated with an increased incidence of common infections but not influenza or fungal infections. This study does not support a protective role of statins in infection prevention; however, the influence of potential confounders cannot be excluded.

Boots for Achilles: progesterone's reduction of cholesterol is a second-order adaptation

Progesterone and cholesterol are both vital to pregnancy. Among other functions, progesterone downregulates inflammatory responses, allowing for maternal immune tolerance of the fetal allograft. Cholesterol a key component of cell membranes, is important in intracellular transport, cell signaling, nerve conduction, and metabolism Despite the importance of each substance in pregnancy, one exercises an antagonistic effect on the other, as periods of peak progesterone correspond with reductions in cholesterol availability, a consequence of progesterone's negative effects on cholesterol biosynthesis. This arrangement is understandable in light of the threat posed by pathogens early in pregnancy. Progesterone-induced immunomodulation entails increased vulnerability to infection, an acute problem in the first trimester, when fetal development is highly susceptible to insult. Many pathogens rely on cholesterol for cell entry, egress, and replication. Progesterone's antagonistic effects on cholesterol thus partially compensate for the costs entailed by progesterone-induced immunomodulation. Among pathogens to which the host's vulnerability is increased by progesterone's effects, approximately 90% utilize cholesterol, and this is notably true of pathogens that pose a risk during pregnancy. In addition to having a number of possible clinical applications, our approach highlights the potential importance of second-order adaptations, themselves a consequence of the lack of teleology in evolutionary processes.

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.

The "Mevalonate hypothesis": a cholesterol-independent alternative for the etiology of atherosclerosis

The “cholesterol hypothesis” is the leading theory to explain the cause of atherosclerosis. The “cholesterol hypothesis” assumes that plasma (LDL) cholesterol is an important causal factor for atherosclerosis.

However, data of at least seven placebo controlled randomized prospective trials with various cholesterol lowering drugs show that plasma cholesterol lowering does not necessarily lead to protection against cardiovascular disease. Therefore an alternative hypothesis for the etiology of cardiovascular disease is formulated. This alternative hypothesis, the “mevalonate hypothesis”, assumes that after stimulation of the mevalonate pathway in endothelial cells by inflammatory factors, these cells start producing cholesterol and free radicals. In this hypothesis, only the latter play a role in the etiology of atherosclerosis by contributing to the formation of oxidized cholesterol which is a widely accepted causal factor for atherosclerosis.

Regardless of how the mevalonate pathway is activated (by withdrawal of statin drugs, by inflammatory factors or indirectly by reduced intracellular cholesterol levels) in all these cases free radical production is observed as well as cardiovascular disease. Since in the “mevalonate hypothesis” cholesterol is produced at the same time as the free radicals causing atherosclerosis, this hypothesis provides an explanation for the correlation which exists between cardiovascular disease and plasma cholesterol levels. From an evolutionary perspective, concomitant cholesterol production and free radical production in response to inflammatory factors makes sense if one realizes that both activities potentially protect cells and organisms from infection by gram-negative bacteria.

In conclusion, data have been collected which suggest that activation of the mevalonate pathway in endothelial cells is likely to be a causal factor for atherosclerosis. This “mevalonate hypothesis” provides a better explanation for results obtained from recent clinical studies with cholesterol lowering drugs than the “cholesterol hypothesis”. Furthermore, this hypothesis explains how cholesterol can be correlated with cardiovascular disease without being a causal factor for it. Finally it provides a logical explanation for the etiology of this disease.

Cholesterol as a Mediator of Alcohol-Induced Risks for Respiratory Disease Hospitalizations among People Living With HIV

We analyzed the role of cholesterol as a potential mediator of alcohol-increased risk of respiratory infections that required hospitalization in People Living with HIV (PLWH). Using a longitudinal clinic-based design, 346 PLWH were consecutively admitted and followed at Jackson Memorial Medical Center(enrolled in the study). Following national guidelines, PLWH were stratified according to cholesterol levels: <150 mg/dl (Hypocholesterolemia= HypoCHL), 151-200, and >200 mg/dl Hypercholesterolemia =HyperCHL), and compared on the basis of clinical outcomes, lymphocyte phenotypes and behavioral risks. Analyses indicated that compared to HyperCHL participants, HypoCHL subjects were more likely to be hospitalized, particularly for lower respiratory tract infections (LRTI). Excessive admissions were associated with more deviant lymphocyte profiles, particularly limited NK cells. In logistic regression analyses, smoking (OR=1.5), HypoCHL (OR=7.7), and alcohol (OR=1.2) were predictors of LRTI. These findings warrant further investigation of the potential use of HypoCHL as a risk marker, and the cost-effectiveness of switching prevention gears towards HypoCHL, alcohol and tobacco in PLWH.

Low cholesterol? Don't brag yet ... hypocholesterolemia blunts HAART effectiveness: a longitudinal study

BACKGROUND

In vitro studies suggest that reducing cholesterol inhibits HIV replication. However, this effect may not hold in vivo, where other factors, such as cholesterol's immunomodulatory properties, may interact.

METHODS

Fasting blood samples were obtained on 165 people living with HIV at baseline and after 24 weeks on highly active antiretroviral therapy (HAART). Participants were classified as hypocholesterolemic (HypoCHL; <150 mg/dl) or non-HypoCHL (>150 mg/dl) and were compared on viro-immune outcomes.

RESULTS

At baseline, participants with HypoCHL (40%) exhibited lower CD4 (197 +/- 181 vs. 295 +/- 191 cells/mm3, p = 0.02) and CD8 (823 +/- 448 vs. 1194 +/- 598 cells/mm3, p = 0.001) counts and were more likely to have detectable viral loads (OR = 3.5, p = 0.01) than non-HypoCHL controls. After HAART, participants with HypoCHL were twice as likely to experience a virological failure >400 copies (95% CI 1-2.6, p = 0.05) and to exhibit <200 CD4 (95% CI 1.03-2.9, p = 0.04) compared with non-HypoCHL. Low thymic output was related to poorer CD4 cell response in HypoCHL subjects. Analyses suggest a dose-response relationship with every increase of 50 mg/dl in cholesterol related to a parallel rise of 50 CD4 cells.

CONCLUSIONS

The study implicates, for the first time, HypoCHL with impaired HAART effectiveness, including limited CD4 repletion by the thymus and suboptimal viral clearance.

Serum lipid profile: a predictor of clinical outcome in dengue infection

OBJECTIVES

To correlate serum lipoproteins levels with dengue severity, clinical outcome (patient survival), bleeding severity, capillary leakage, supportive care requirement and hospital stay duration.

METHODS

Single centre, prospective study.

SETTING

Tertiary care hospital.

SUBJECTS

50 (1 month-18 years) dengue fever cases and 50 age and sex matched non-febrile controls. Methods: patients were classified (WHO criteria) as dengue fever (DF), dengue haemorrhagic fever (DHF), dengue shock syndrome (DSS). Bleeding score; serum triglyceride, cholesterol, HDL, LDL and VLDL was determined. Statistical analysis was done using Chi-squared test with continuity correction, Unpaired t-test, ANOVA with post hoc test, Binary logistic and multinomial regression.

RESULTS

18 (36%) patients were DF, 19 (38%) DHF and 13 (26%) DSS. Lowest cholesterol, VLDL levels seen in DSS and highest in DF. Mean cholesterol level is significantly lower in expired patients and patients with third spacing. Severe bleeding significantly correlated with cholesterol level and hepatic dysfunction but not with platelet count or coagulopathy. Duration of intravenous fluid requirement and packed cell requirement negatively correlated with HDL and cholesterol levels. Fresh frozen plasma requirement negatively correlated with TG, HDL, VLDL and cholesterol levels. Platelet transfusion requirement and duration of hospital stay did not correlate with lipid levels. Intensive care and ventilator requirement negatively correlated with cholesterol level; inotrope requirement negatively correlated with HDL level. Ventilator requirement correlated negatively with TG levels also.

CONCLUSIONS

Lipid profile changes accompany dengue infection, some of which may indicate severity and guide therapy.

HDL-cholesterol and physical performance: results from the ageing and longevity study in the sirente geographic area (ilSIRENTE Study)

BACKGROUND

High-density lipoprotein (HDL) cholesterol has been hypothesised to be a reliable marker of frailty and poor prognosis among the oldest elderly. We evaluate the relationship of HDL-cholesterol with measures of physical performance, muscle strength, and functional status in older persons aged 80years or older.

METHODS

Data are from baseline evaluation of the ageing and longevity study in the Sirente geographic area (ilSIRENTE study) (n = 364). Physical performance was assessed using the physical performance battery score [short physical performance battery (SPPB)], which is based on three-timed tests: 4-m walking-speed, balance, and chair-stand tests. Muscle strength was measured by hand-grip strength. Analyses of covariance were performed to evaluate the relationship of different HDL-cholesterol levels with physical function.

RESULTS

In the unadjusted analyses, physical function (as measured by the 4-m walking-speed, theSPPB score, the basic and instrumental activities of daily living scales scores), but not hand-grip strength, improved significantly as HDL-cholesterol tertiles increased. After adjustment for potential confounders, which included age, gender, living alone, alcohol abuse, physical activity, congestive heart failure, diabetes, cerebrovascular diseases, osteoarthritis, albumin, urea, C-reactive protein and LDL cholesterol, the association of HDL-cholesterol tertiles with the 4-m walking-speed and the SPPB score was still consistent.

CONCLUSION

The present study suggests that among very old subjects living in the community the higher levels of HDL-cholesterol are associated with better functional performance.

Effects of infectious disease on plasma lipids and their diagnostic significance in critical illness

BACKGROUND

Plasma lipids can be affected by acute illnesses. The present study attempts to characterize the impact of infectious disease on plasma lipids in critical illness. It also aims to determine the value of plasma lipid routine measurements in the diagnosis of infection in critical illness in comparison to markers of infection and acute phase reactants.

MATERIALS AND METHODS

An observational study was carried out in 101 critically ill patients admitted consecutively to a medical intensive care unit in a university medical centre. Levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), and additional variables were measured in blood samples taken on the day of admission.

RESULTS

In critically ill patients significantly lower levels of HDL-C and TC were found in infectious disease patients compared to non-infectious disease patients (P < 0.001). No significant differences in levels of TG were found between infectious and non-infectious disease patients. Using receiver operating characteristic (ROC) curve analysis, the area under the curve (AUC) value for HDL-C and TC in the diagnosis of infection was 0.791 (P < 0.001) and 0.730 (P < 0.001), respectively. At a cutoff value for HDL-C of </= 0.78 mmol L(-1), a sensitivity of 71.7% and a specificity of 86.0% were recorded. The AUC value of HDL-C was significantly (P < 0.001) inferior to procalcitonin (AUC: 0.967, P < 0.001) and non-significantly inferior to C-reactive protein (CRP) (AUC: 0.874, P < 0.001). HDL-C correlated with albumin (r = 0.7, P < 0.001) and CRP (r = -0.54, P < 0.001), but not with the Acute Physiology and Chronic Health Evaluation II score. There was no significant difference between the plasma lipid concentrations in survivors and non-survivors.

CONCLUSION

In critically ill infected patients, HDL-C and TC levels are lower than in non-infected critically ill patients. In this study the diagnostic accuracy of CRP is not better than the one of HDL-C. The diagnostic accuracy of procalcitonin is superior to HDL-C.

Statins do not improve short-term survival in an oriental population with sepsis

OBJECTIVES

The aim of this study was to define the effect of statin on 30-day mortality in an oriental population with sepsis.

DESIGN

We conducted a retrospective study on patients with sepsis at National Taiwan University Hospital from 2001 to 2002. The effects of statins on 30-day mortality were evaluated based on clinical settings. Log-rank test and Cox regression analysis were performed using the proportional hazards assumption.

RESULTS

A total of 763 episodes of sepsis were reviewed; 454 consecutive patients were considered eligible. Among them, 104 (22.9%) took a statin at least 30 days before admission and during sepsis course, whereas the other 350 control (77.1%) did not. There was no significant difference of 30-day sepsis-related mortality between groups (19.2% vs 18.9%, P = .952). Statin treatment was not associated with decreased mortality at 30 days (P = .853; risk ratio, 0.95; 95% confidence interval, 0.53-1.68).

CONCLUSION

Short-term, sepsis-related mortality in a septic Taiwanese population was not reduced with statin treatment in our study. We concluded that statin therapy may have little effect on the survival of sepsis in oriental people, particularly in Taiwanese.

Serum Uric Acid as an Independent Predictor of Early Death After Acute Stroke

BACKGROUND

The prognostic significance of uric acid (UA) levels in acute stroke is unclear, so the objective of this study was to determine the association between levels of serum UA (SUA) and mortality in acute stroke.

METHODS AND RESULTS

Consecutive patients (n=435) presenting with ischemic stroke and intracerebral hemorrhage were included in the study. The length of stay in hospital and the occurrence of death were recorded. On univariate analysis, the occurrence of death was associated with older age, smoking, presence of congestive heart failure or atrial fibrillation, absence of hyperlipidemia, and intracerebral hemorrhage as the index event. Furthermore, glucose, urea, creatinine and SUA at admission were significantly higher in patients who died, whereas total and high-density-lipoprotein cholesterol were significantly lower. On multiple logistic regression analysis, the independent relationship between higher SUA levels and death was confirmed (odds ratio (OR), 1.37; 95%confidence interval (CI), 1.13-1.67; p=0.001). The only other variables independently associated with the occurrence of death were urea concentration and presence of atrial fibrillation. If urate was >7.8 mg/dl (0.47 mmol/L), then there would be a high probability of early death (87%).

CONCLUSIONS

Elevated levels of SUA are independently associated with an increased risk of early death in acute stroke.

[Estimation of effect of lipid lowering treatment on total mortality rate and its cost-effectiveness determined by intervention study of hypercholesterolemia]

OBJECTIVES

Total cholesterol (TC) level reduction decreases coronary heart disease (CHD) risk, but it is also associated with an increase in non-CHD mortality rate. Our objectives are to estimate the effect of TC level reduction on total mortality and other mortalities in the Japanese population using published data and to analyze the cost-effectiveness of drug therapy.

METHODS

We analyzed three data sets for the estimation. The first data set comprised Japanese mortality rates of cardiac diseases, cerebrovascular/other vascular diseases, malignancy, and all causes according to sex and age. The second data set comprised the distributions of serum TC levels in the Japanese population. The third data set comprised the relative risks of mortality rates for the above causes according to the TC level classified into discrete intervals of 20 mg/dl from an intervention study. We estimated the mortality rates of people aged 30-69, with each TC level classification group on the basis of each cause. On the assumption that TC level decreases from 240-259 mg/dl to 160-179 mg/dl or 180-199 mg/dl with drug therapy, we calculated the differences between the mortalities of the classification. When we found a positive effect of TC level reduction, we performed cost-effectiveness analyses of Number Needed to Treat (NNT).

RESULTS

TC level reduction increased the mortality rates except for that of cardiac diseases, and the NNT for cardiac diseases was in the range of 4,202-17,533. The cost of simvastatin, for example, was 0.25-1.05 billion yen per year.

CONCLUSIONS

TC level reduction from 240-259 mg/dl to 160-199 mg/dl leads to an increase in total mortality rate in the Japanese population. The treatment should be reevaluated from both viewpoints of risk benefit and cost-effectiveness.

Lipoproteins in inflammation and sepsis. II. Clinical aspects

BACKGROUND

Systemic inflammation and sepsis are accompanied by severe metabolic alterations, including insulin resistance together with increased levels of triglycerides (TGs) and decreases in high- and low-density lipoproteins. Clinical studies have clearly established a link between lipid metabolism and systemic inflammation. Lipoproteins were shown to neutralize LPS and to exert direct anti-inflammatory actions. High- and low-density lipoproteins are thus thought to be important regulators of the host immune response during endotoxemia, which may also have the potential of improving the care of patients with Gram-negative sepsis.

DISCUSSION

Nutritional lipids supplied during critical illness have been shown to modulate the host response to inflammation. In particular, inclusion of omega-3 fatty acids seems to have beneficial effects on cellular immunity and helps to maintain the balance between pro- and anti-inflammatory cytokines thereby preventing hyperinflammatory complications. In addition to improvements in the profile of lipid mediators generated, omega-3 fatty acids act as activating ligands of peroxisome proliferator-activated receptors and directly inhibit nuclear factor kappaB mediated proinflammatory signaling. We present an overview on the alterations in the metabolism of serum lipoproteins during sepsis and present data from clinical studies and discuss the significance of nutritional lipids and their role in immunomodulation with special emphasis on omega-3 fatty acids.

Total Serum Cholesterol and Recovery From Disability Among Hospitalized Older Adults

BACKGROUND

The association between total serum cholesterol and health outcomes among older adults is controversial. The objective of the present study was to determine within a cohort of acutely hospitalized disabled elderly patients whether total cholesterol predicts recovery from disability in basic activities of daily living (ADL).

METHODS

Patients (3150) 65 years old or older admitted to 81 acute care units in Italy and presenting with ADL disability at hospital admission were included in this study. ADL disability was defined as need of assistance or total dependence in one or more ADLs (eating, dressing, personal hygiene, transferring, and toilet use). Recovery was defined as no disability at hospital discharge in any of the five ADLs considered.

RESULTS

Mean age of study participants was 80.5 +/- 7.2 years, and 1305 (41.1%) were men. The rate of recovery from ADL disability was 14.5% for participants with total cholesterol < 200 mg/dL (n = 306/2108), 20.2% for those with total cholesterol between 200 and 239 mg/dL (n = 144/713), and 23.1% for those with total cholesterol > or = 240 mg/dL (n = 76/329). After adjustment for potential confounders, relative to that of patients with cholesterol < 200 mg/dL, risk ratios for recovery were 1.31 for participants with cholesterol between 200 and 239 mg/dL (95% confidence interval [CI], 1.07-1.62) and 1.36 (95% CI, 1.04-1.79) for those with cholesterol > or = 240 mg/dL. After exclusion of 769 patients with total cholesterol < 145 mg/dL, the risk ratios (compared with those for participants with cholesterol < 200 mg/dL) for recovery were 1.33 (95% CI, 1.07-1.66) for participants with cholesterol between 200 and 239 mg/dL and 1.41 (95% CI, 1.06-1.88) for patients with cholesterol > or = 240 mg/dL.

CONCLUSIONS

Among hospitalized disabled older adults, elevated levels of cholesterol are associated with increased rate of recovery from ADL disability.

Statins: panacea for sepsis?

Sepsis occurs when the immune system responds to a localised infection at a systemic level, thereby causing tissue damage and organ dysfunction. Statins have proven health benefits in many diseases involving vascular inflammation and injury. Recent animal data suggest that the administration of a statin before a sepsis-inducing insult reduces morbidity and improves survival. The immunomodulatory and anti-inflammatory effects of statins, collectively referred to as pleiotropic effects, lend biological plausibility to such findings. Limited human data hint at reduced mortality rates in bacteraemic patients, and a reduced risk of sepsis in patients with bacterial infections concurrently taking statins. These lines of evidence point to a potential new treatment and prevention modality for sepsis. The stage is set for randomised controlled clinical trials that will determine whether statins represent a safe and beneficial treatment in critically ill, septic patients and whether statins are effective at preventing sepsis in high-risk clinical settings.