Prospective study of markers of hemostatic function with risk of ischemic stroke. The Atherosclerosis Risk in Communities (ARIC) Study Investigators

Development of a Hypercoagulable-Hypofibrinolytic State Early After Spinal Cord Injury

OBJECTIVES

To determine whether spinal cord injury (SCI) is associated with adverse changes in coagulation and fibrinolytic factors that underlie thrombogenesis and contribute to atherothrombotic events such as myocardial infarctions (MIs) and strokes.

DESIGN

Cross-sectional study.

SETTING

Neurorehabilitation hospital and general community.

PARTICIPANTS

Thirty young and middle-aged (20-58 years) adults (N=30) were studied: 14 non-injured community dwelling adults. (11M/4F) and 16 with subacute tetraplegic motor complete SCI during initial inpatient rehabilitation (13M/3F; time since injury: 11.8±5.3 wk).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Circulating markers of coagulation [von Willebrand factor (vWf) and factors VII, VIII, and X], the fibrinolytic system [tissue-type plasminogen activator (t-PA), and plasminogen activator inhibitor-1 (PAI-1) antigen and activity], and fibrin formation (D-dimer) were determined by enzyme immunoassay.

RESULTS

Thirty young and middle-aged (20-58 years) adults were studied: 14 non-injured (11M/4F) and 16 with subacute tetraplegic motor complete SCI (13M/3F; time since injury: range 4-25 wk). Circulating levels of coagulation factors VII, VIII, and X were significantly higher (∼20%-45%; P<.05) in the adults with SCI than non-injured adults, whereas vWf was similar between groups. Fibrinolytic markers were adversely disrupted with SCI with t-PA antigen, PAI-1 antigen and PAI-1 activity were markedly higher (∼50%-800%; P<.05) in adults with SCI compared with non-injured adults. The molar concentration ratio of active t-PA to PAI-1 was significantly higher (∼350%) in adults with SCI. Concordant with coagulation cascade activation and fibrinolytic system inhibition, D-dimer concentrations were markedly ∼70% higher (P<.05) in adults with SCI compared with non-injured adults.

CONCLUSIONS

Subacute tetraplegic motor complete SCI is associated with a prothrombotic hemostatic profile. Adverse changes in the coagulation cascade and fibrinolytic system appear to occur early after injury and may contribute to the increased atherothrombotic risk in adults living with SCI.

REVIEWING THE DYSREGULATION OF ADAMTS13 AND VWF IN SEPSIS

ABSTRACT

Sepsis is defined as a life-threatening organ dysfunction caused by excessive host response to infection, and represents the most common cause of in-hospital deaths. Sepsis accounts for 30% of all critically ill patients in the intensive care unit (ICU), and has a global mortality rate of 20%. Activation of blood coagulation during sepsis and septic shock can lead to disseminated intravascular coagulation, which is characterized by microvascular thrombosis. Von Willebrand factor (VWF) and ADAMTS13 are two important regulators of blood coagulation that may be important links between sepsis and mortality in the ICU. Herein we review our current understanding of VWF and ADAMTS13 in sepsis and other critical illnesses and discuss their contribution to disease pathophysiology, their use as markers of severe illness, and potential targets for new therapeutic development.

Midlife Hemostasis Measures, 20-Year Cognitive Decline, and Incident Dementia

BACKGROUND AND OBJECTIVES

Blood concentrations of hemostatic factors affect thrombosis and bleeding diathesis and may contribute to cognitive impairment through modifiable vascular pathologies. Whether hemostasis, assessed in middle age, is associated with late-life cognitive impairment remains largely unknown in a community-dwelling population.

METHODS

Using data from 14,128 participants with cognitive function measurements in 1990-1992 from the Atherosclerosis Risk in Communities study, we assessed the associations of hemostasis measures with 20-year changes in cognitive performance and incident dementia. Activated partial thromboplastin time (aPTT) and level of fibrinogen, von Willebrand factor (VWF), factor VIII, factor VII, factor XI, d-dimer, and soluble thrombomodulin were measured in 1987-1989 or 1993-1995. Hemostasis measures were categorized into quintiles, with the lowest quintile indicating low coagulability. Cognitive performance was characterized using a combined z-score from 3 tests (that is, delayed word recall test [DWRT], digit symbol substitution [DSST], and word fluency test [WFT]), assessed in 1990-1992, 1996-1998, and 2011-2013. Dementia was determined either from in-person evaluations or using dementia surveillance through 2017. Mixed-effects models and Cox proportional hazards models were used to assess cognitive trajectories and risk of dementia, respectively.

RESULTS

Among 12,765 participants with hemostasis measures in 1987-1989, who were aged 47-70 years at the first cognitive assessment, we observed significant trends of shorter aPTT (p for trend <0.001; difference in 20-year cognitive decline for fifth vs first quintile [Q5 vs Q1]: -0.104 [95% CI -0.160 to -0.048]) and higher levels of factor VII (p < 0.002; Q5 vs Q1: -0.085 [-0.142, -0.028]) and factor VIII (p = 0.033; Q4 vs Q1: -0.055 [-0.111, -0.000]) with greater 20-year cognitive declines. The associations with the decline in DSST were stronger than those with the decline in WFT or DWRT. Consistently, shorter aPTT and higher factor VIII levels were associated with higher dementia risk with HRs for Q5 vs Q1 of 1.23 (95% CI 1.07 to 1.42) and 1.17 (1.01-1.36), respectively, and p for trend of 0.008 and 0.024, respectively.

DISCUSSION

Overall, our study found consistent trend associations of aPTT and factor VIII measured in midlife with cognitive decline and incident dementia over 20 years, likely driven by vascular pathologies.

Inflammation biomarkers are associated with the incidence of cardiovascular disease: a meta-analysis

Background

Inflammation is a risk factor for cardiovascular disease (CVD), and particular inflammatory parameters can be used to predict the incidence of CVD. The aim of this study was to assess the association between fibrinogen (FIB), interleukin-6 (IL-6), C-reactive protein (CRP) and galectin-3 (Gal-3) and the risk of cardiovascular disease using meta-analysis.

Methods

PubMed, Embase, Scopus, and Web of Science databases were searched with the appropriate strategies to identify observational studies relevant to this meta-analysis. A random-effects model was used to combine inflammation factor-associated outcomes and cardiovascular disease outcomes, except in the case of galectin-3, where a fixed-effects model was used because of less heterogeneity. Location, age, type of cardiovascular disease, and sample size factors were used to explore heterogeneity in stratification and metaregression for subgroup analysis. A case-by-case literature exclusion approach was used for sensitivity analysis. The funnel plot and Begg's test were combined to assess publication bias.

Results

Thirty-three papers out of 11,456 were screened for inclusion in the analysis. Four inflammation biomarkers were significantly associated with the development of CVD: FIB (OR: 1.21, 95% CI: 1.15-1.27, P < 0.001; HR: 1.04, 95% CI: 1.00-1.07, P < 0.05), IL-6 (HR: 1.16, 95% CI: 1.10-1.22, P < 0.001), CRP (OR: 1.25, 95% CI: 1.15-1.35, P < 0.001; HR: 1.20, 95% CI: 1.14-1.25, P < 0.001) and Gal-3 (HR: 1.09, 95% CI: 1.05-1.14, P < 0.001). Location factors help explain the source of heterogeneity, and there is publication bias in the Gal-3 related literature.

Conclusion

Taken together, the current research evidence suggests that high levels of fibrinogen, interleukin-6, C-reactive protein and galectin-3 are risk factors for cardiovascular disease and can be used as biomarkers to predict the development of cardiovascular disease to some extent.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO, identifier: CRD42023391844.

Coagulation biomarkers for ischemic stroke

A State of the Art lecture titled "coagulation biomarkers for ischemic stroke" was presented at the International Society on Thrombosis and Haemostasis (ISTH) Congress in 2022. Ischemic stroke (IS) is a common disease with major morbidity and mortality. It is a challenge to determine which patients are at risk for IS or have poor clinical outcome after IS. An imbalance of coagulation markers may contribute to the progression and prognosis of IS. Therefore, we now discuss studies on the association of selected coagulation biomarkers from the hemostasis, inflammation, and immunothrombosis systems with the risk of IS, stroke severity at the acute phase, and clinical outcome after treatment. We report on coagulation biomarker-induced risk of IS, stroke severity, and outcomes following IS derived from prospective population studies, case-control studies, and acute-phase IS studies. We found indications that many coagulation and inflammation biomarkers are associated with IS, but it is early to conclude that any of these biomarkers can be applied in a therapeutic setting to predict patients at risk of IS, stroke severity at the acute phase, and clinical outcome after treatment. The strongest evidence for a role in IS was found for beta-thromboglobulin, von Willebrand factor, factor VIII, fibrinogen, thrombin-activatable fibrinolysis inhibitor, D-dimer, and neutrophil extracellular traps, and therefore, they are promising candidates. Further research and validation in large-size populations using well-defined study designs are warranted. Finally, we provide a selection of recent data relevant to this subject that was presented at the 2022 ISTH Congress.

The relative risk of ischemic cerebrovascular accident in patients with Von Willebrand disease

Cerebrovascular accident (CVA) is one of the leading causes of death in the United States. Von Willebrand factor plays an important role in platelet activation and adhesion. It remains unclear whether Von Willebrand disease (vWD) is associated with a decreased risk of developing CVA. The study aimed to compare the relative risk (RR) of CVA in patients with and without vWD. We queried the National Inpatient Sample from 2009 to 2014 for discharge data and records for vWD and CVA using International Classification of Diseases, Ninth-Revision codes. The unadjusted and adjusted RR of CVA in patients with and without vWD were estimated using log-binomial model. Descriptive measures including means, medians, standard deviations, and range were presented based on normality test of continuous data. The prevalence of CVA was lower in patients with vWD than in those without vWD (1.31% vs 2.04%), with a RR of 0.64 (95% confidence interval (CI): 0.60-0.68). After adjusting for common CVA risk factors, the RR remained lower in vWD patients: 0.81 (95% CI: 0.76-0.86). vWD is associated with a lower RR of developing CVA. This suggests that deficiency of Von Willebrand factor is potentially protective against the development of CVA. To the best of our knowledge, this is the first study in humans to compare the RR of CVA in patients with and without vWD. Future studies are needed to explore causal relationships and therapeutic benefits.

Blood biomarkers for new-onset hypertension in midlife women: a nested case-control study

OBJECTIVE

Midlife in women is associated with an increase in prevalence of hypertension. Little is known on the risk factors of new-onset hypertension among middle-aged women.

METHODS

In this nested case-control study, 1,430 women aged 40 to 60 years with repeated physical examinations between 2009 and 2019 were recruited. Data included age, body mass index, blood pressure (BP), and a series of blood biomarkers. Participants with hypertension were divided into two case-control samples: 388 cases with episodic new-onset hypertension (ie, one normal BP at the first visit and one abnormal BP during follow-up) each with two age-matched controls (n = 776) and 151 cases with regular new-onset hypertension (ie, normal BP at the first two visits and abnormal BP at two or more follow-up visits) each with three age-matched controls (n = 453). Multivariable-adjusted logistic regression was used to analyze the data.

RESULTS

Our data showed very consistent results for episodic and regular new-onset hypertension, respectively, and verified known associations (odds ratio [95% confidence interval], per SD increase) with obesity (body mass index, 1.72 [1.49-1.98] and 1.81 [1.45-2.26]), inflammation (white blood cell count, 1.39 [1.23-1.58] and 1.38 [1.13-1.69]), and metabolic dysregulation (triglycerides, 1.25 [1.09-1.44] and 1.31 [1.08-1.58]; glucose, 1.46 [1.23-1.73] and 1.27 [1.05-1.54]) but, more surprisingly, also revealed positive associations with red blood cell count (1.27 [1.11-1.44] and 1.38 [1.14-1.68]), hemoglobin (1.18 [1.03-1.35] and 1.31 [1.05-1.64]), and platelet count (1.39 [1.20-1.61] and 1.33 [1.09-1.63]).

CONCLUSIONS

In addition to obesity and metabolic dysregulation, increased hemoglobin and counts of platelets, and red and white blood cells are associated with hypertension in this period. Future study may verify whether these associations are causal in nature and whether these variables are useful in risk stratification.

Lower levels of vWF are associated with lower risk of cardiovascular disease

Objective

The current study was undertaken to prospectively explore whether having low levels of von Willebrand factor (vWF) antigen and vWF activity reduce the risk for cardiovascular disease and death.

Methods

VWF antigen and vWF activity were measured by enzyme-linked immunosorbent assay and an immunological-based assay, respectively, in a subsample of 4857 individuals aged between 35 and 74 years old, enrolled between April 2007 and October 2008 in the population-based Gutenberg Health Study. VWF antigen and activity below the 20th percentile was set as a measure of "low vWF." Adjusted robust Poisson regression models were used to analyze the relation between low vWF and the incidence of cardiovascular disease (CVD). Consequent adjusted cox regression models as well as cumulative incidence plots were calculated to explore the relation between all-cause and cardiovascular mortality and low vWF.

Results

VWF activity levels <20th percentile (i.e., <76.2%) were associated with a decreased relative risk for CVD (RR: 0.59, 95% CI: 0.37-0.95), despite adjusting for age and sex. After adjusting for levels of F-VIII, the association persisted (RR: 0.60, 95% CI: 0.36-0.99). The cumulative incidence plots demonstrated that vWF antigen <20th percentile significantly correlated with decreased cardiovascular mortality. VWF antigen<20th percentile (i.e., <83%) was significantly associated with lower risk of all-cause mortality, despite adjusting for clinical factors (RR: 61, 95% CI: 0.41-0.91).

Conclusion

The study demonstrated that having low vWF activity levels were associated with a lower risk for CVD. Additionally, it revealed a decreased risk of cardiovascular and all-cause mortality in individuals with low levels of vWF antigen, shining new light on vWF as a potential target for novel therapies.

Successful Outcome in an Adolescent with Artery of Percheron Occlusion who was Treated with Tissue Plasminogen Activator

BACKGROUND

Ischemic stroke is relatively rare in children, leading to a low level of suspicion and delayed diagnosis, particularly in cases of posterior circulation occlusion when symptoms are less indicative. Occlusion of the artery of Percheron (AOP) results in nonspecific neurologic symptoms, including drowsiness, aphasia or dysarthria, ophthalmoplegia, ataxia, and dysmetria. Previous reports, mainly in adults, described late diagnosis and severe residual disability.

CASE REPORT

We report a case of a 16-year-old male who presented to the pediatric emergency department with altered mental status. There was no history of trauma or intoxication. The main symptoms included confusion, slurred speech, and multiple falls starting 1 h before arrival to the emergency department. No motor deficits or other focal signs were noticed. The patient's consciousness gradually decreased followed by apneic events. Routine laboratory tests, urinary toxic screen, and a computed tomography scan of the head were normal. A magnetic resonance imaging scan of the brain revealed bilateral restrictive changes in the thalamus. A diagnosis of AOP occlusion was made, and the patient was treated with tissue plasminogen activator (6 h after symptom onset). He was extubated on day 4 and discharged on the day 10 of admission without any neuropsychological deficit. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Posterior circulation stroke in the pediatric population is a diagnostic challenge that often results in suboptimal treatment and unfavorable outcomes. Prompt imaging studies in children with nonspecific altered mental status enable timely diagnosis and thrombolytic treatment that may substantially improve the outcome.

Associations of Hemostatic Variables with Cardiovascular Disease and Total Mortality: The Glasgow MONICA Study

The associations of plasma levels of hemostatic factors, other than fibrinogen, with risks of cardiovascular disease (CVD) and all-cause mortality are not well defined. In two phases of the Glasgow MONICA study, we assayed coagulation factors (VII, VIII, IX, and von Willebrand factor), coagulation inhibitors (antithrombin, protein C, protein S), coagulation activation markers (prothrombin fragment 1 + 2, thrombin–antithrombin complexes, D-dimer), and the fibrinolytic factors, tissue plasminogen activator (t-PA) antigen and plasminogen activator inhibitor type 1. Over 15 to 20 years, we followed up between 382 and 1,123 men and women aged 30 to 74 years, without baseline CVD, for risks of CVD and mortality. Age- and sex-adjusted hazard ratios (HRs) for CVD (top third vs bottom third) were significant only for factor VIII (1.30; 95% confidence interval [CI], 1.06–1.58) and factor IX (1.18; 95% CI, 1.01–1.39); these HRs were attenuated by further adjustment for CVD risk factors: 1.17 (95% CI, 0.94–1.46) and 1.07 (95% CI, 0.92–1.25), respectively. In contrast, factor VIII (HR, 1.63; 95% CI, 1.35–1.96), D-dimer (HR, 2.34; 95% CI, 1.26–4.35), and t-PA (HR, 2.81; 95% CI, 1.43–5.54) were strongly associated with mortality after full risk factor adjustment. Further studies, including meta-analyses, are required to assess the associations of these hemostatic factors with the risks of stroke and heart disease and causes of mortality.

Subcortical infarction in a young adult with Hunter syndrome

INTRODUCTION

Hunter syndrome (mucopolysaccharidosis type II, MPS II) is an X-linked lysosomal storage disease caused by deficiency of iduronate-2-sulfatase. Recently, stroke caused by embolization with Hunter syndrome has been reported. Here, we report the case of a 23-year-old Japanese man with Hunter syndrome who developed subcortical infarction by the mechanism similar to branch atheromatous disease (BAD).

CASE PRESENTATION

He had been treated with idursulfase supplementation. He presented with left-sided weakness and conjugate eye deviation to the right, and was diagnosed with branch atheromatous disease affecting the right corona radiata, based on MRI findings. The patient was treated with argatroban and aspirin. Magnetic resonance angiography demonstrated no evidence of luminal narrowing of the cerebral arteries. T1-sampling perfection with application-optimized contrasts by using different flip angle evolutions (SPACE) imaging revealed thickened middle cerebral artery. The patient had markedly low flow-mediated vasodilation, suggesting impaired vasodilation in response to nitric monoxide.

CONCLUSION

The arterial wall thickening and impaired vasodilation in the cerebral arteries related to subcortical infarction. We should clarify the mechanism of cerebral infarction in Hunter syndrome patients.

Associations between fibrinogen levels and the risk of cardiovascular disease and all-cause death: a cohort study from the Chin-Shan community in Taiwan

OBJECTIVES

Although several studies have investigated the association between fibrinogen level and the risk of cardiovascular disease (CVD), few studies have been conducted in Asia.

SETTING

We conducted a community-based prospective cohort study in the Chin-Shan community, Taiwan.

PARTICIPANTS

A total of 2222 participants (54.6±11.9 years, 53.4% women, and 22.4 years of follow-up) who underwent plasma fibrinogen measurements and were without CVD at baseline were recruited, among which 735 participants with available C reactive protein (CRP) were included in the joint analysis of the association of fibrinogen and CRP levels with the risk of CVD.

PRIMARY AND SECONDARY OUTCOME MEASURES

Fibrinogen and CRP levels were measured by clotting and high-sensitivity immunoturbidimetric assays, respectively. The study outcomes were CVD events and all-cause death. Our definition of CVD included both coronary artery disease (CAD) and stroke cases. Cox proportional hazards regression models were used to estimate the HRs and 95% CIs.

RESULTS

Compared with the lowest quartile, participants with higher fibrinogen levels tended to have a higher risk of CAD (adjusted HR for the highest quartile=1.48 (95% CI 0.90 to 2.44); test for trend p=0.037) regardless of CRP level (adjusted HR=2.12 (95% CI 1.24 to 3.63) and 2.17 (95% CI 1.06 to 4.44) for high fibrinogen/low CRP and high fibrinogen/high CRP, respectively). The association was not observed for stroke (adjusted HR for the highest quartile=0.99 (95% CI 0.62 to 1.60); test for trend p=0.99) and was only observed for all-cause death among participants <65 years of age (adjusted HR for the highest quartile=1.47 (95% CI 1.11 to 1.95); test for trend p=0.004).

CONCLUSIONS

Fibrinogen may be a potential risk factor for CAD but not for stroke. Further studies are necessary to clarify the differences in the role of fibrinogen levels on the risk of CVD between Asian and Western countries.

Atherothrombotic factors and atherosclerotic cardiovascular events: the multi-ethnic study of atherosclerosis

AIMS

Traditional atherosclerotic cardiovascular disease (ASCVD) risk factors fail to address the full spectrum of the complex interplay of atherosclerotic and atherothrombotic factors integral to ASCVD events. This study sought to examine the association between atherothrombotic biomarkers and ASCVD events.

METHODS AND RESULTS

The association between atherothrombotic biomarkers and 877 ASCVD events with and without adjustment for traditional risk factors was evaluated via Cox proportional hazards models and factor analysis in 5789 Multi-Ethnic Study of Atherosclerosis participants over a median follow-up of 14.7 years. Factor analysis accounted for multidimensional relationship and shared variance among study biomarkers, which identified two new variables: a thrombotic factor (Factor 1), principally defined by shared variance in fibrinogen, plasmin-antiplasmin complex, factor VIII, D-dimer, and lipoprotein(a), and a fibrinolytic factor (Factor 2), principally defined by shared variance of plasminogen and oxidized phospholipids on plasminogen. In a model including both factors, the thrombotic factor was associated with the higher risk of ASCVD events [hazard ratio (HR) 1.57, 95% confidence interval (CI) 1.45, 1.70], while the fibrinolytic factor was associated with the lower risk of ASCVD events (HR 0.76, 95% CI 0.70, 0.82), with estimated ASCVD free survival highest for low atherothrombotic Factor 1 and high atherothrombotic Factor 2.

CONCLUSION

Two atherothrombotic factors, one representative of thrombotic propensity and the other representative of fibrinolytic propensity, were significantly and complementarily associated with incident ASCVD events, remained significantly associated with incident ASCVD after controlling for traditional risk factors, and have promise for identifying patients at high ASCVD event risk specifically due to their atherothrombotic profile.

ASSOCIATIONS OF HAEMOSTATIC VARIABLES WITH CARDIOVASCULAR DISEASE AND TOTAL MORTALITY - THE GLASGOW MONICA STUDY

The associations of plasma levels of hemostatic factors, other than fibrinogen, with risks of cardiovascular disease (CVD) and all-cause mortality are not well defined. In two phases of the Glasgow MONICA study, we assayed coagulation factors (VII, VIII, IX, and von Willebrand factor), coagulation inhibitors (antithrombin, protein C, protein S), coagulation activation markers (prothrombin fragment 1 + 2, thrombin–antithrombin complexes, D-dimer), and the fibrinolytic factors, tissue plasminogen activator (t-PA) antigen and plasminogen activator inhibitor type 1. Over 15 to 20 years, we followed up between 382 and 1,123 men and women aged 30 to 74 years, without baseline CVD, for risks of CVD and mortality. Age- and sex-adjusted hazard ratios (HRs) for CVD (top third vs bottom third) were significant only for factor VIII (1.30; 95% confidence interval [CI], 1.06–1.58) and factor IX (1.18; 95% CI, 1.01–1.39); these HRs were attenuated by further adjustment for CVD risk factors: 1.17 (95% CI, 0.94–1.46) and 1.07 (95% CI, 0.92–1.25), respectively. In contrast, factor VIII (HR, 1.63; 95% CI, 1.35–1.96), D-dimer (HR, 2.34; 95% CI, 1.26–4.35), and t-PA (HR, 2.81; 95% CI, 1.43–5.54) were strongly associated with mortality after full risk factor adjustment. Further studies, including meta-analyses, are required to assess the associations of these hemostatic factors with the risks of stroke and heart disease and causes of mortality.

Collateral Circulation Augmentation and Neuroprotection as Adjuvant to Mechanical Thrombectomy in Acute Ischemic Stroke

PURPOSE OF THE REVIEW

Mechanical thrombectomy (MT)-mediated endovascular recanalization has dramatically transformed treatment and outcomes after acute ischemic stroke caused by a large vessel occlusion (LVO). Current guidelines recommend MT up to 24 hours from stroke onset in carefully selected patients based on favorable clinical and imaging parameters. Despite optimal patient selection and low complication rates with current recanalization technology, approximately 1 in 2 patients with LVO stroke do not achieve functional independence at 3 months. This ceiling effect of MT efficacy may be explained by ischemic core expansion into the ischemic penumbra before recanalization and neuronal loss occurring after recanalization. Factors affecting the efficacy of MT, or the degree of irreversible injury, include time from symptom onset to recanalization, collateral circulation status, and differences in neuronal vulnerability. The purpose of this brief review is to discuss potential targets for neuroprotection, present and future potential pharmacologic and nonpharmacologic agents, and the data available in the literature.

RECENT FINDINGS

In experimental ischemia models, several authors reported that pharmacologic and nonpharmacologic agents are able to slow the progression of ischemic core expansion. However, in the era of unsuccessful recanalization of the occluded artery, several neuroprotective agents that were promising in the preclinical stage failed phase II/III clinical trials.

SUMMARY

Providing neuroprotection before and after recanalization of an LVO may play an important role in improving outcomes in the era of MT. Neuroprotection is classically defined as a process that results in the salvage, recovery, or regeneration of neuronal (and other supporting CNS cell) structure or function. The advent of successful recanalization of acute LVO by MT in the majority of patients may spur the growth of effective neuroprotection.

Current Therapeutic Approach to Acute Myocardial Infarction in Patients with Congenital Hemophilia

Advances in the treatment of hemophilia have made the life expectancy of hemophiliacs similar to that of the general population. Physicians have begun to face age-related diseases not previously encountered in individuals with hemophilia. Treatment of acute myocardial infarction (AMI) is particularly challenging because the therapeutic strategies influence both the patient's thrombotic and hemorrhagic risk. As progress has been made in the treatment of AMI over the last decade, we performed an in-depth analysis of the available literature, highlighting the latest advances in the therapy of AMI in hemophiliacs. It is generally accepted that after the optimal substitution therapy has been provided, patients with hemophilia should be treated in the same way as those in the general population. New-generation stents that allow short dual antiplatelet therapy and potent P2Y12 receptor inhibitors have begun to be successfully used. At a time when specific recommendations and relevant data are scarce, our study provides up-to-date information to physicians involved in the treatment of AMI in hemophiliacs.

Gut microbiota and their metabolites in cardiovascular disease

The gut microbiome affects the development and progress of various types of disease such as obesity, diabetes, atherosclerosis and arterial thrombosis. Gut microbiome derived metabolites have been established to be predictive of arterial thrombosis in epidemiological studies. In these studies atherosclerosis and prothrombotic effect cannot be distinguished but preclinical studies show gut derived metabolites can induce platelet hyperreactivity and increase thrombotic potential. Gut commensals can also influence platelets through serotonin synthesis and may enhance Von Willebrand factor production. The effects on secondary haemostasis are less studied. In antiphospholipid syndrome, a thrombotic auto-immune disorder, autoreactive T cells and antibodies cross-react with auto-antigen mimicking peptides from gut commensals which appears to contribute to the pathophysiology. This review focusses on the prothrombotic effect of the gut microbiome and aims to provide insight into its influence on thromboembolic disease and the haemostatic system.

Von Willebrand Factor, Factor VIII, and Other Acute Phase Reactants as Biomarkers of Inflammation and Endothelial Dysfunction in Chronic Graft-Versus-Host Disease

Chronic graft-versus-host disease (cGvHD) is an immune mediated late complication of allogeneic hematopoietic stem cell transplantation (alloHSCT). Discovery of adequate biomarkers could identify high-risk patients and provide an effective pre-emptive intervention or early modification of therapeutic strategy, thus reducing prevalence and severity of the disease among long-term survivors of alloHSCT. Inflammation, endothelial injury, and endothelial dysfunction are involved in cGvHD development. Altered levels of acute phase reactants have shown a strong correlation with the activity of several immune mediated disorders and are routinely used in clinical practice. Since elevated von Willebrand factor (VWF) and factor VIII (FVIII) levels have been described as acute phase reactants that may indicate endothelial dysfunction and inflammation in different settings, including chronic autoimmune diseases, they could serve as potential candidate biomarkers of cGvHD. In this review we focused on reported data regarding VWF and FVIII as well as other markers of inflammation and endothelial dysfunction, evaluating their potential role in cGvHD.

Prognostic Utility of the Combination of Platelet Count with Neutrophil-to-Lymphocyte Ratio in Aged Patients with Acute Myocardial Infarction Undergoing Percutaneous Coronary Intervention

Method

This was a study recording 637 patients who were diagnosed with acute myocardial infarction. Our patients were grouped according to the combination of platelet count and neutrophil-to-lymphocyte ratio. The prognostic role of the combination of platelet count and neutrophil-to-lymphocyte ratio on mortality was assessed by the univariate and multivariate Cox regression analysis.

Result

Our study population was divided into three parts according to the median values of platelet count and neutrophil-to-lymphocyte ratio. It was indicated that platelet count and neutrophil-to-lymphocyte ratio were correlative mutually to a certain degree (p=0.010). The Kaplan–Meier analysis showed that the combination of high platelet count and high neutrophil-to-lymphocyte ratio had a greater risk of death in short- and long-term endpoints (log-rank p=0.046, p < 0.001, respectively). Moreover, by multivariate analysis, both high platelet count and high neutrophil-to-lymphocyte ratio groups were an independent predictor (hazard ratio: 2.132, 95% confidence interval: 1.020–4.454, p=0.044) and long-term mortality (hazard ratio: 2.791, 95% confidence interval: 1.406–5.538, p=0.003).

Conclusion

The combination of platelet count and neutrophil-to-lymphocyte ratio could be a useful predictor for the prediction of in-hospital and long-term mortality in aged patients with acute myocardial infarction.

Clinical significance of measuring ADAMTS-13, its inhibitor and von Willebrand factor in obstetric and gynecological practice

ADAMTS-13 is a crucial metalloproteinase involved in liberating fragments of von Willebrand factor (vWF) into the plasma as well as regulating its activity by cleaving "ultra-large" multimers into smaller and less active counterparts. Many pathological conditions, including those emerged during pregnancy are characterized by increased level of vWF and decreased ADAMTS-13 activity. In this regard, it is necessary to monitor the levels of vWF and ADAMTS-13 activity to prevent thrombotic thrombocytopenic purpura (Moschcowitz disease) as one of the most severe forms of thrombotic microangiopathy.

 

Identifying Genetic and Biological Determinants of Race-Ethnic Disparities in Stroke in the United States

In the United States, causes of racial differences in stroke and its risk factors remain only partly understood, and there is a long-standing disparity in stroke incidence and mortality impacting Black Americans. Only half of the excess risk of stroke in the United States Black population is explained by traditional risk factors, suggesting potential effects of other factors including genetic and biological characteristics. Here, we nonsystematically reviewed candidate laboratory biomarkers for stroke and their relationships to racial disparities in stroke. Current evidence indicates that IL-6 (interleukin-6), a proinflammatory cytokine, mediates racial disparities in stroke through its association with traditional risk factors. Only one reviewed biomarker, Lp(a) (lipoprotein[a]), is a race-specific risk factor for stroke. Lp(a) is highly genetically determined and levels are substantially higher in Black than White people; clinical and pharmaceutical ramifications for stroke prevention remain uncertain. Other studied stroke risk biomarkers did not explain racial differences in stroke. More research on Lp(a) and other biological and genetic risk factors is needed to understand and mitigate racial disparities in stroke.

von Willebrand Factor Antigen, von Willebrand Factor Propeptide, and ADAMTS13 in Carotid Stenosis and Their Relationship with Cerebral Microemboli

BACKGROUND

 The relationship between von Willebrand factor antigen (VWF:Ag), VWF propeptide (VWFpp), VWFpp/VWF:Ag ratio, ADAMTS13 activity, and microembolic signal (MES) status in carotid stenosis is unknown.

METHODS

 This prospective, multicenter study simultaneously assessed plasma VWF:Ag levels, VWFpp levels and ADAMTS13 activity, and their relationship with MES in asymptomatic versus symptomatic moderate-to-severe (≥50-99%) carotid stenosis patients. One-hour transcranial Doppler ultrasound of the middle cerebral arteries classified patients as MES+ve or MES-ve.

RESULTS

 Data from 34 asymptomatic patients were compared with 43 symptomatic patients in the "early phase" (≤4 weeks) and 37 patients in the "late phase" (≥3 months) after transient ischemic attack (TIA)/ischemic stroke. VWF:Ag levels were higher (p = 0.049) and VWFpp/VWF:Ag ratios lower (p = 0.006) in early symptomatic than in asymptomatic patients overall, and in early symptomatic versus asymptomatic MES-ve subgroups (p ≤0.02). There were no intergroup differences in VWFpp expression or ADAMTS13 activity (p ≥0.05). VWF:Ag levels and ADAMTS13 activity decreased (p ≤ 0.048) and VWFpp/VWF:Ag ratios increased (p = 0.03) in symptomatic patients followed up from the early to late phases after TIA/stroke. Although there were no differences in the proportions of symptomatic and asymptomatic patients with blood group O, a combined analysis of early symptomatic and asymptomatic patients revealed lower median VWF:Ag levels in patients with blood group O versus those without blood group O (9.59 vs. 12.32 µg/mL, p = 0.035).

DISCUSSION

 VWF:Ag expression, a marker of endothelial ± platelet activation, is enhanced in recently symptomatic versus asymptomatic carotid stenosis patients, including in MES-ve patients, and decreases with ADAMTS13 activity over time following atherosclerotic TIA/ischemic stroke.

Hemostatic Adaptations to High Intensity Interval Training in Healthy Adult Men

Regular exercise is theorized to reduce cardiovascular risk by attenuating coagulation and augmenting fibrinolysis. However, these adaptations have not been consistently observed during traditional exercise programs. The purpose of this study was to examine hemostatic adaptations in healthy men following four (4W) and eight (8W) weeks of high intensity interval training. Twenty-one men (age=25±1 y; body mass index=26.5±6.4 kg/m²) completed eight weeks, three days/week of high intensity interval training on a cycle ergometer. Activated partial thromboplastin time, prothrombin time, and plasma concentrations of thrombin-antithrombin III, fibrinogen, tissue plasminogen activator, and plasminogen activator inhibitor-1 were assessed at baseline (BL), 4W, and 8W. Repeated measures ANOVA were used to determine potential effects of training. There were no significant changes observed for activated partial thromboplastin time (BL=43.3±5.5, 4W=43.2±5.1, 8W=44.2±6.4 s); prothrombin time (BL=13.2±0.9, 4W=13.0±0.6, 8W=13.1±0.8 s); thrombin-antithrombin III (BL=6.0±2.3, 4W=5.8±2.3, 8W=5.6±3.1 ng/mL); tissue plasminogen activator (BL=9.7±3.3, 4W=9.4±3.2, 8W=8.7±2.8 ng/mL); and plasminogen activator inhibitor-1 (BL=19.0±17.5, 4W=19.3±17.0, 8W=18.9±18.9 ng/mL) (all p>0.05). Fibrinogen was significantly lower at 4W (238.6±70.3 mg/dL) compared to BL (285.0±82.1 mg/dL; p<0.05) and 8W (285.3±83.2 mg/dL; p<0.05). These findings indicate that eight weeks of high intensity interval training does not influence coagulation potential and/or stimulate fibrinolysis.

Additive effect of erythropoietin use on exercise-induced endothelial activation and hypercoagulability in athletes

Purpose

Recombinant human erythropoietin (rHuEPO) is known to increase thrombotic risk in patients and might have similar effects in athletes abusing the drug. rHuEPO is prohibited by anti-doping legislation, but this risk has not been investigated thoroughly. This analysis was designed to evaluate whether rHuEPO impacts hemostatic profile and endothelial and platelet activation markers in trained subjects, and whether the combination with exercise affects exercise induced alterations.

Methods

This double-blind, randomized, placebo-controlled trial enrolled healthy, trained male cyclists aged 18–50 years. Participants were randomly allocated (1:1) to receive subcutaneous injections of rHuEPO (epoetin-β; mean dose 6000 IU per week) or placebo (0.9% NaCl) for 8 weeks. Subjects performed five maximal exercise tests and a road race, coagulation and endothelial/platelet markers were measured at rest and directly after each exercise effort.

Results

rHuEPO increased P-selectin (+ 7.8% (1.5–14.5), p = 0.02) and E-selectin (+ 8.6% (2.0–15.7), p = 0.01) levels at rest. Maximal exercise tests significantly influenced all measured coagulation and endothelial/platelet markers, and in the rHuEPO group maximal exercise tests led to 15.3% ((7.0–24.3%), p = 0.0004) higher E-selectin and 32.1% ((4.6–66.8%), p = 0.0207) higher Platelet factor 4 (PF4) levels compared to the placebo group.

Conclusion

In conclusion, rHuEPO treatment resulted in elevated E- and P-selectin levels in trained cyclists, indicating enhanced endothelial activation and/or platelet reactivity. Exercise itself induces hypercoagulability, and the combination of rHuEPO and exercise increased E-selectin and PF4 levels more than either intervention alone. Based on this, exercise potentially increases thrombotic risk, a risk that might be enhanced in combination with rHuEPO use.

Electronic supplementary material

The online version of this article (10.1007/s00421-020-04419-0) contains supplementary material, which is available to authorized users.

Coagulation factor VIII: Relationship to cardiovascular disease risk and whole genome sequence and epigenome-wide analysis in African Americans

BACKGROUND

Prospective studies have suggested higher factor VIII (FVIII) levels are an independent risk factor for coronary heart disease (CHD) and stroke. However, limited information, including on genetic and epigenetic contributors to FVIII variation, is available specifically among African Americans (AAs), who have higher FVIII levels than Europeans.

OBJECTIVES

We measured FVIII levels in ~3400 AAs from the community-based Jackson Heart Study and assessed genetic, epigenetic, and epidemiological correlates of FVIII, as well as incident cardiovascular disease (CVD) associations.

METHODS

We assessed cross-sectional associations of FVIII with CVD risk factors as well as incident CHD, stroke, heart failure, and mortality associations. We additionally assessed associations with TOPMed whole genome sequencing data and an epigenome-wide methylation array.

RESULTS

Our results confirmed associations between FVIII and risk of incident CHD events and total mortality in AAs; mortality associations were largely independent of traditional risk factors. We also demonstrate an association of FVIII with incident heart failure, independent of B-type natriuretic peptide. Two genomic regions were strongly associated with FVIII (ABO and VWF). The index variant at VWF is specific to individuals of African descent and is distinct from the previously reported European VWF association signal. Epigenome-wide association analysis showed significant FVIII associations with several CpG sites in the ABO region. However, after adjusting for ABO genetic variants, ABO CpG sites were not significant.

CONCLUSIONS

Larger sample sizes of AAs will be required to discover additional genetic and epigenetic contributors to FVIII phenotypic variation, which may have consequences for CVD health disparities.

Association of PC and AT levels in the early phase of STEMI treated with pPCI with LV systolic function and 6-month MACE

OBJECTIVES

To examine a relationship between protein C (PC) and antithrombin III (AT III) activities with ejection fraction of left ventricle (EFLV), in the early phase of acute ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (pPCI), and to investigate whether PC and AT III are associated with major adverse cardiovascular events (MACE) within 6 months following from pPCI.

PATIENTS AND METHODS

The research had a prospective character and included 357 patients who had, following the diagnosis of the STEMI, undergone pPCI at the Clinic of Cardiology and Emergency Internal Medicine, Military Medical Academy, Belgrade, Serbia, from January 2010 until April 2019.

RESULTS

The EFLV positively correlated with PC values (rho = 0.229). There was a statistically significant increase in the PC values between patients with MACE compared with those without MACE at 6 months' follow-up evaluation (p < 0.0001). Also, significant difference in PC values between patients who died in hospital and those who were alive at 6 months' follow-up (p < 0.01) was observed. PC values were different across different EFLV groups (p < 0.001), increasing from the 1st to the 4th EFLV quartiles: the median and the interquartile values for the 1st, 2nd, 3rd and 4th quartiles were 1.0400IU/l ± 0.15, 1.1400IU/l ± 0.15, 1.1350IU/l ± 0.16 and 1.2200IU/l ± 0.14, respectively.

CONCLUSION

Increased PC activity in the early phase of STEMI is associated with higher EFLV 5 days after the pPCI as well as with MACE at 6 months after the pPCI.

Systemic Inflammatory Markers Among Waterpipe Smokers, Cigarette Smokers, and Nonsmokers

OBJECTIVE

To determine the levels of neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) among exclusive groups of waterpipe (WP) smokers, cigarette smokers, and nonsmokers.

METHODS

This cross-sectional study was conducted among adults, apparently healthy individuals, aged between 18 and 40 years of either gender. NLR and PLR as measures of systemic inflammation were studied in association with individuals' sociodemographic, health, and tobacco use related characteristics. The results of linear and logistic regression models were reported as crude and adjusted beta coefficients and odds ratios with 95% confidence intervals (CIs).

RESULTS

Out of 190 participants, 34.2% (n = 65) exclusively smoked WP, 32.6% (n = 62) smoked cigarettes, and 33.2% (n = 63) were nonsmokers. The mean NLR and PLR were significantly higher among WP smokers when compared with nonsmokers; however, the comparison between WP smokers and cigarette smokers for both NLR and PLR was not statistically significant. The odds of raised NLR was 4.40 times higher (AOR = 4.40, 95% CI = 1.97, 9.85), and the odds of raised PLR was 3.48 times higher (AOR = 3.48, 95% CI = 1.60, 7.57) for WP smokers compared to nonsmokers.

CONCLUSIONS

WP smoking has a significant association with systemic inflammation as measured by NLR and PLR. The study and existing evidence implicate an urging need to regulate WP industry and its policies.

The effect of intramuscular megadose of vitamin D injections on E-selectin, CRP and biochemical parameters in vitamin D-deficient patients with type-2 diabetes mellitus: A randomized controlled trial

BACKGROUND AND AIMS

Inflammatory processes has been shown to be associated with the development of type 2 diabetes mellitus (T2DM) in which vitamin D supplementation might exert beneficial outcomes. We examined the effects of vitamin D supplement on inflammatory and cell adhesion molecule in patients with T2DM.

METHODS

This study consisted of 50 patients with T2DM who had vitamin D deficiency. Participants were randomized into two groups of 25 in which the intervention group received two intramuscular injections of a 200000-IU vitamin D supplement, one at week 0 and another at week 4. The concentrations of fasting blood glucose (FBG), lipid profiles, liver enzymes, E-selectin, C-reactive protein (CRP), calcium, phosphorus, serum 25-hydroxyvitamin D [25(OH)D] and anthropometric indices were obtained before and after 8 weeks.

RESULTS

Vitamin D resulted in significant reductions in CRP(P = 0.01) and gamma glutamyl transferase (GGT) levels(P = 0.03) and significant increases in 25(OH)D concentrations(P = 0.01) in the intervention group compared with the control. Within-group comparisons showed that FBG decreased significantly in the intervention group(P = 0.04). No significant changes were observed regarding within- and between-group comparisons of the other markers.

CONCLUSION

Vitamin D had beneficial effects on the levels of CRP, serum 25(OH)D and GGT among vitamin D deficient patients with T2DM. (http://www.irct.ir: IRCT2017100336539N1).

Prognostic Hemostasis Biomarkers in Acute Ischemic Stroke

Supplemental Digital Content is available in the text.

Objectives—

The prediction of patients at risk for poor clinical outcome after acute ischemic stroke remains challenging. An imbalance of coagulation factors may play an important role in progression and prognosis of these patients. In this systematic review, we assessed the current literature on hemostasis biomarkers and the association with poor clinical outcome in acute ischemic stroke.

Approach and Results—

A systematic search of Embase, Medline, Cochrane Library, Web of Science, and Google Scholar was performed on studies reporting on hemostasis biomarkers and clinical outcome after acute ischemic stroke. Studies were considered eligible if blood samples were collected within 72 hours after symptom onset. Additionally, clinical outcome should be assessed using a disability score (Barthel Index or modified Rankin scale). Methodological quality of included studies was assessed with an adapted version of the Quality Assessment of Diagnostic Accuracy Studies questionnaire. A total of 80 articles were read full text, and 41 studies were considered eligible for inclusion, reporting on 37 different hemostasis biomarkers. No single biomarker appeared to be effective in predicting poor clinical outcome in acute ischemic stroke patients.

Conclusions—

Based on current literature, no clear recommendations can be provided on which hemostasis biomarkers are a predictor of clinical outcome after acute ischemic stroke. However, some biomarkers show promising results and need to be further investigated and validated in large populations with clear defined study designs.

Circulating Biomarkers in Migraine: New Opportunities for Precision Medicine

Background:

Migraine is the most common neurological disorder and the second most disabling human condition, whose pathogenesis is favored by a combination of genetic, epigenetic, and environmental factors. In recent years, several efforts have been made to identify reliable biomarker(s) useful to monitor disease activity and/or ascertain the response to a specific treatment.

Objective:

To review the current evidence on the potential biological markers associated with migraine.

Methods:

A structured search of peer-reviewed research literature was performed by searching major publications databases up to December 2017.

Results:

Several circulating biomarkers have been proposed as diagnostic or therapeutic tools in migraine, mostly related to migraine’s inflammatory pathophysiological aspects. Nonetheless, their detection is still a challenge for the scientific community, reflecting, at least in part, disease complexity and clinical diagnostic limitations. At the present time, calcitonin generelated peptide (CGRP) represents probably the most promising candidate as a diagnostic and/or therapeutic biomarker, as its plasma levels are elevated during migraine attack and decrease during successful treatment. Other molecules (including some neuropeptides, cytokines, adipokines, or vascular activation markers) despite promising, do not possess the sufficient prerequisites to be considered as migraine biomarkers.

Conclusion:

The characterization of migraine-specific biomarkers would be fundamental in a perspective of precision medicine, enabling risk assessment and tailored treatments. However, speculating on the clinical validity of migraine biomarkers may be premature and controlled clinical trials are presently needed to investigate both the diagnostic and therapeutic value of these biomarkers in migraine.

Arterial and venous thrombosis by high platelet count and high hematocrit: 108 521 individuals from the Copenhagen General Population Study

BACKGROUND

It is unclear whether high platelet count or high hematocrit predict risk of thrombosis in individuals from the general population.

OBJECTIVES

We tested the hypothesis that individuals from the general population with high platelet count or high hematocrit have high risk of arterial and venous thrombosis.

METHODS

We prospectively followed 108 521 individuals from The Copenhagen General Population Study for a median of 8 years. Platelet count and blood hematocrit were measured at study entry.

RESULTS AND CONCLUSION

Multivariable adjusted hazard ratios for individuals with platelet counts in the top 5 percentiles (>398 × 109 /L) vs in the 25th-75th percentiles (231-316 × 109 /L) were 1.77 (95% confidence interval [CI], 1.38-2.24) for arterial thrombosis in the brain (38 and 26 events/10 000 person-years) and 0.82 (95%, 0.61-1.11) for arterial thrombosis in the heart (23 and 28 events/10 000 person-years). For individuals with hematocrit values in the top 5 percentiles (women/men: >45/>48%) vs the 25th-75th percentiles (women/men: 38.1-42/41.1-45%), hazard ratios were 1.27 (95% CI, 0.91-1.75) for arterial thrombosis in the brain (40 and 26 events/10 000 person-years) and 1.46 (95% CI, 1.06-2.00) for arterial thrombosis in the heart (43 and 25 events/10 000 person-years). Neither high platelet count nor high hematocrit was associated with risk of venous thromboembolism. When excluding individuals with myeloproliferative neoplasia from the main analyses, results on risk of thrombosis were similar. In this prospective study, high platelet counts were associated with 1.8-fold risk of arterial thrombosis in the brain, whereas high hematocrit was associated with 1.5-fold risk of arterial thrombosis in the heart.

Activated protein C in neuroprotection and malaria

PURPOSE OF REVIEW

Activated protein C (APC) is a homeostatic coagulation protease with anticoagulant and cytoprotective activities. Focusing on APC's effects in the brain, this review discusses three different scenarios that illustrate how APC functions are intimately affecting the physiology and pathophysiology of the brain.

RECENT FINDINGS

Cytoprotective APC therapy holds promise for the treatment of ischemic stroke, and a recently completed trial suggested that cytoprotective-selective 3K3A-APC reduced bleeding in ischemic stroke patients. In contrast, APC's anticoagulant activity contributes to brain bleeding as shown by the disproportional upregulation of APC generation in cerebral cavernous malformations lesions in mice. However, too little APC generation also contributes to maladies of the brain, such as in case of cerebral malaria where the binding of infected erythrocytes to the endothelial protein C receptor (EPCR) may interfere with the EPCR-dependent functions of the protein C pathway. Furthermore, discoveries of new activities of APC such as the inhibition of the NLRP3-mediated inflammasome and of new applications of APC therapy such as in Alzheimer's disease and graft-versus-host disease continue to advance our knowledge of this important proteolytic regulatory system.

SUMMARY

APC's many activities or lack thereof are intimately involved in multiple neuropathologies, providing abundant opportunities for translational research.

Vascular cognitive impairment: pathophysiological mechanisms, insights into structural basis, and perspectives in specific treatments

Vascular cognitive impairment (VCI) and vascular dementia are the most common forms of cognitive disorder associated with cerebrovascular disease and related to increased morbidity and mortality among the older population. Growing evidence suggests the contribution of blood-pressure variability, cardiac arrhythmia, hyperactivation of the renin-angiotensin-aldosterone system, endothelial dysfunction, vascular remodeling and stiffness, different angiopathies, neural tissue homeostasis, and systemic metabolic disorders to the pathophysiology of VCI. In this review, we focus on factors contributing to cerebrovascular disease, neurovascular unit alterations, and novel approaches to cognitive improvement in patients with cognitive decline. One of the important factors associated with the neuronal causes of VCI is the S100B protein, which can affect the expression of cytokines in the brain, support homeostasis, and regulate processes of differentiation, repair, and apoptosis of the nervous tissue. Since the pathological basis of VCI is complex and diverse, treatment affecting the mechanisms of cognitive disorders should be developed. The prospective role of a novel complex drug consisting of released-active antibodies to S100 and to endothelial NO synthase in VCI treatment is highlighted.

Activated protein C, protease activated receptor 1, and neuroprotection

Protein C is a plasma serine protease zymogen whose active form, activated protein C (APC), exerts potent anticoagulant activity. In addition to its antithrombotic role as a plasma protease, pharmacologic APC is a pleiotropic protease that activates diverse homeostatic cell signaling pathways via multiple receptors on many cells. Engineering of APC by site-directed mutagenesis provided a signaling selective APC mutant with 3 Lys residues replaced by 3 Ala residues, 3K3A-APC, that lacks >90% anticoagulant activity but retains normal cell signaling activities. This 3K3A-APC mutant exerts multiple potent neuroprotective activities, which require the G-protein-coupled receptor, protease activated receptor 1. Potent neuroprotection in murine ischemic stroke models is linked to 3K3A-APC-induced signaling that arises due to APC's cleavage in protease activated receptor 1 at a noncanonical Arg46 site. This cleavage causes biased signaling that provides a major explanation for APC's in vivo mechanism of action for neuroprotective activities. 3K3A-APC appeared to be safe in ischemic stroke patients and reduced bleeding in the brain after tissue plasminogen activator therapy in a recent phase 2 clinical trial. Hence, it merits further clinical testing for its efficacy in ischemic stroke patients. Recent studies using human fetal neural stem and progenitor cells show that 3K3A-APC promotes neurogenesis in vitro as well as in vivo in the murine middle cerebral artery occlusion stroke model. These recent advances should encourage translational research centered on signaling selective APC's for both single-agent therapies and multiagent combination therapies for ischemic stroke and other neuropathologies.

Targeting von Willebrand Factor in Ischaemic Stroke: Focus on Clinical Evidence

Despite great efforts in stroke research, disability and recurrence rates in ischaemic stroke remain unacceptably high. To address this issue, one potential target for novel therapeutics is the glycoprotein von Willebrand factor (vWF), which increases in thrombogenicity especially under high shear rates as it bridges between vascular sub-endothelial collagen and platelets. The rationale for vWF as a potential target in stroke comes from four bodies of evidence. (1) Animal models which recapitulate the pathogenesis of stroke and validate the concept of targeting vWF for stroke prevention and the use of the vWF cleavage enzyme ADAMTS13 in acute stroke treatment. (2) Extensive epidemiologic data establishing the prognostic role of vWF in the clinical setting showing that high vWF levels are associated with an increased risk of first stroke, stroke recurrence or stroke-associated mortality. As such, vWF levels may be a suitable marker for further risk stratification to potentially fine-tune current risk prediction models which are mainly based on clinical and imaging data. (3) Genetic studies showing an association between vWF levels and stroke risk on genomic levels. Finally, (4) studies of patients with primary disorders of excess or deficiency of function in the vWF axis (e.g. thrombotic thrombocytopenic purpura and von Willebrand disease, respectively) which demonstrate the crucial role of vWF in atherothrombosis. Therapeutic inhibition of VWF by novel agents appears particularly promising for secondary prevention of stroke recurrence in specific sub-groups of patients such as those suffering from large artery atherosclerosis, as designated according to the TOAST classification.

Associations of activated coagulation factor VII and factor VIIa-antithrombin levels with genome-wide polymorphisms and cardiovascular disease risk

ESSENTIALS

Essentials A fraction of coagulation factor VII circulates in blood as an activated protease (FVIIa). We evaluated FVIIa and FVIIa-antithrombin (FVIIa-AT) levels in the Cardiovascular Health Study. Polymorphisms in the F7 and PROCR loci were associated with FVIIa and FVIIa-AT levels. FVIIa may be an ischemic stroke risk factor in older adults and FVIIa-AT may assess mortality risk.

SUMMARY

Background A fraction of coagulation factor (F) VII circulates as an active protease (FVIIa). FVIIa also circulates as an inactivated complex with antithrombin (FVIIa-AT). Objective Evaluate associations of FVIIa and FVIIa-AT with genome-wide single nucleotide polymorphisms (SNPs) and incident coronary heart disease, ischemic stroke and mortality. Patients/Methods We measured FVIIa and FVIIa-AT in 3486 Cardiovascular Health Study (CHS) participants. We performed a genome-wide association scan for FVIIa and FVIIa-AT in European-Americans (n = 2410) and examined associations of FVII phenotypes with incident cardiovascular disease. Results In European-Americans, the most significant SNP for FVIIa and FVIIa-AT was rs1755685 in the F7 promoter region on chromosome 13 (FVIIa, β = -25.9 mU mL-1 per minor allele; FVIIa-AT, β = -26.6 pm per minor allele). Phenotypes were also associated with rs867186 located in PROCR on chromosome 20 (FVIIa, β = 7.8 mU mL-1 per minor allele; FVIIa-AT, β = 9.9 per minor allele). Adjusted for risk factors, a one standard deviation higher FVIIa was associated with increased risk of ischemic stroke (hazard ratio [HR], 1.12; 95% confidence interval [CI], 1.01, 1.23). Higher FVIIa-AT was associated with mortality from all causes (HR, 1.08; 95% CI, 1.03, 1.12). Among European-American CHS participants the rs1755685 minor allele was associated with lower ischemic stroke (HR, 0.69; 95% CI, 0.54, 0.88), but this association was not replicated in a larger multi-cohort analysis. Conclusions The results support the importance of the F7 and PROCR loci in variation in circulating FVIIa and FVIIa-AT. The findings suggest FVIIa is a risk factor for ischemic stroke in older adults, whereas higher FVIIa-AT may reflect mortality risk.

Relationship between neighborhood socioeconomic status and venous thromboembolism: results from a population-based study

Essentials Literature on socioeconomic status (SES) and incidence of venous thromboembolism (VTE) is scarce. We assessed neighborhood SES with VTE risk in a population of over 1.4 million inhabitants. Higher neighborhood SES was associated with lower incidence of VTE. These findings are helpful to inform policy and resource allocation in health systems.

SUMMARY

Background The association between socioeconomic status and arterial cardiovascular disease is well established. However, despite its high burden of disability-adjusted life years, little research has been carried out to determine whether socioeconomic status is associated with venous thromboembolism. Objective To determine if neighborhood socioeconomic status is associated with venous thromboembolism in a population-based study from the Netherlands. Methods We identified all patients aged 15 years and older with a first event of venous thromboembolism from inhabitants who lived in the urban districts of The Hague, Leiden and Utrecht in the Netherlands in 2008-2012. Neighborhood socioeconomic status was based on the status score, which combines educational level, income and unemployment on a four-digit postal code level. Incidence rate ratios of venous thromboembolism were calculated for different levels of neighborhood socioeconomic status, with adjustments for age and sex. Results A total of 7373 patients with a first venous thromboembolism (median age 61 years; 50% deep vein thrombosis) were identified among more than 1.4 million inhabitants. Higher neighborhood SES was associated with lower incidence of VTE. In the two highest status score groups (i.e. the 95-99th and > 99th percentile), the adjusted incidence rate ratios were 0.91 (95% confidence interval [CI], 0.84-1.00) and 0.80 (95% CI, 0.69-0.93), respectively, compared with the reference status score group (i.e. 30-70th percentile). Conclusions High neighborhood socioeconomic status is associated with a lower risk of first venous thromboembolism.

The relevance of coagulation in cardiovascular disease: what do the biomarkers tell us?

Several haemostatic factors have been associated with incident arterial cardiovascular disease in prospective studies and meta-analyses. Plasma fibrinogen shows a strong and consistent association with risk; however, this may reflect its inflammatory marker status, and causality remains to be proven. The common haemostatic gene polymorphisms for factor II, factor V and the von Willebrand factor: Factor VIII (non-O blood group) show significant associations with coronary heart disease (CHD) risk, consistent with potential causality. Increased D-dimer and t-PA antigen levels are associated with CHD risk, suggesting roles for coagulation activation and endothelial disturbance. There is little evidence for associations with CVD with other haemostatic factors.

A plasma proteomics method reveals links between ischemic stroke and MTHFR C677T genotype

Methylene Tetrahydrofolate Reductase (MTHFR) catalyzes the conversion of methylene tetrahydrofolate to methylte trahydrofolate. The 677th nucleotide of the MTHFR gene is often regarded as a risk factor of cardiovascular disease. Previous studies demonstrated an elevated risk of ischemic stroke with the MTHFR677TT genotype. In this study, we employed a plasma proteomics method to investigate the connection between the polymorphism of the target nucleotide and stroke. In total, 28 protein spots were differentially expressed between the two groups, and of which, 25 protein spots were up-regulated and 3 were down-regulated. Five randomly selected spots were successfully identified as Haptoglobin (HPT) and Transferrin (TRFE). A functional analysis indicated that most of the differential expressed proteins (DEPs) were related to the inflammatory immune response. A Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that these DEPs were involved in the complement cascade reaction. Meanwhile, protein-protein interactions (PPIs) analysis highlighted the novel association between the C677T MTHFR genotype and Vitamin D binding protein (DBP), which was confirmed by a molecular genetic analysis. The results suggested that the phenotype of the MTHFR might be associated with multiple proteins that have a synergistic effect, which might be related to the mechanism of ischemic stroke.

Associations of coagulation factors IX and XI levels with incident coronary heart disease and ischemic stroke: the REGARDS study

Essentials Coagulation factors (F) IX and XI have been implicated in cardiovascular disease (CVD) risk. We studied associations of FIX and FXI with incident coronary heart disease (CHD) and stroke. Higher FIX antigen was associated with incident CHD risk in blacks but not whites. Higher levels of FIX antigen may be a CHD risk factor among blacks.

SUMMARY

Background Recent studies have suggested the importance of coagulation factor IX and FXI in cardiovascular disease (CVD) risk. Objectives To determine whether basal levels of FIX or FXI antigen were associated with the risk of incident coronary heart disease (CHD) or ischemic stroke. Patients/Methods The REasons for Geographic And Racial Differences in Stroke (REGARDS) study recruited 30 239 participants across the contiguous USA between 2003 and 2007. In a case-cohort study within REGARDS, FIX and FXI antigen were measured in participants with incident CHD (n = 609), in participants with incident ischemic stroke (n = 538), and in a cohort random sample (n = 1038). Hazard ratios (HRs) for CHD and ischemic stroke risk were estimated with Cox models per standard deviation higher FIX or FXI level, adjusted for CVD risk factors. Results In models adjusting for CHD risk factors, higher FIX levels were associated with incident CHD risk (HR 1.19; 95% confidence interval [CI] 1.01-1.40) and the relationship of higher FXI levels was slightly weaker (HR 1.15; 95% CI 0.97-1.36). When stratified by race, the HR of FIX was higher in blacks (HR 1.39; 95% CI 1.10-1.75) than in whites (HR 1.06; 95% CI 0.86-1.31). After adjustment for stroke risk factors, there was no longer an association of FIX levels with ischemic stroke, whereas the association of FXI levels with ischemic stroke was slightly attenuated. Conclusions Higher FIX antigen levels were associated with incident CHD in blacks but not in whites. FIX levels may increase CHD risk among blacks.

Activated protein C promotes neuroprotection: mechanisms and translation to the clinic

Activated protein C (APC) is a plasma serine protease that is capable of antithrombotic, anti-inflammatory, anti-apoptotic, and cell-signaling activities. Animal injury studies show that recombinant APC and some of its mutants are remarkably therapeutic for a wide range of injuries. In particular, for neurologic injuries, APC reduces damage caused by ischemia/reperfusion in the brain, by acute brain trauma, and by chronic neurodegenerative conditions. For these neuroprotective effects, APC requires endothelial cell protein C receptor. APC activates cell signaling networks with alterations in gene expression profiles by activating protease activated receptors 1 and 3. To minimize APC-induced bleeding risk, APC variants were engineered to lack > 90% anticoagulant activity but retain normal cell signaling. The neuroprotective APC mutant, 3K3A-APC which has Lys191-193 mutated to Ala191-193, is very neuroprotective and it is currently in clinical trials for ischemic stroke.

Large Left Ventricular Thrombus in a Patient with Systemic and Venous Thromboembolism Secondary to Protein C and S Deficiency

58-year-old Hispanic female presented with an altered mental status. A CT scan of the head demonstrated multiple scattered infarcts and a large right temporal lobe infarct. We also diagnosed the patient with right popliteal and femoral vein thrombosis, bilateral pulmonary embolism, and a transient right radial artery occlusion. Her 12-lead EKG showed lateral ST elevation. Emergent coronary angiogram revealed normal coronaries. Echocardiogram demonstrated a large mobile mass attached to the anterolateral free wall with overall normal contractility of the left ventricle. The patient underwent surgical embolectomy to prevent further systemic embolization. Coagulability workup returned positive for protein C and S deficiency. The patient did well after surgery. Following her surgery, we initiated chronic oral anticoagulation. The presentation with intracardiac thrombus in a normal heart should raise a concern of a probable thrombophilia.