New-onset hypertension and inflammatory response/poor outcome in acute ischemic stroke

Inhibition of matrix metalloproteinases to reduce blood brain barrier disruption and haemorrhagic transformation in ischaemic stroke: Go broad or go narrow?

Ischaemic stroke characterises impulsive cerebral-region hypoxia due to deep intracerebral arteriole blockage, often accompanied by permanent cerebral infarction and cognitive impairment. Thrombolysis with recombinant tissue plasminogen activator (rtPA) and thrombectomy remain the only guidance-approved therapies. However, emerging data draws clear links between such therapies and haemorrhage transformation, which occur when cerebral vasculature is damaged during ischaemia/reperfusion. Studies have shown that matrix metalloproteinases (MMPs) play a significant role in haemorrhage transformation, by depleting the extracellular matrix (ECM) and disrupting the blood brain barrier (BBB). Inhibitors of MMPs may be used to prevent ischaemic stroke patients from BBB disruption and haemorrhage transformation, particularly for those receiving rtPA treatment. Preclinical studies found that inhibition of MMPs with agents or in knock out mice, effectively reduced BBB disruption and infarct volume, leading to improved ischaemic stroke outcomes. At present, MMP inhibition is not an approved therapy for stroke patients. There remain concerns about timing, dosing, duration of MMP inhibition and selection of either broad spectrum or specific MMP inhibitors for stroke patients. This review aims to summarize current knowledge on MMP inhibition in ischaemic stroke and explore whether a broad spectrum or a specific MMP inhibitor should be used for ischaemic stroke patient treatment. It is crucial to inhibit MMP activities early and sufficiently to ensure BBB intact during ischaemia and reperfusion, but also to reduce side effects of MMP inhibitors to minimum. Recent advance in stroke therapy by thrombectomy could aid in such treatment with intra-arterially delivery of MMP inhibitors (and/or antioxidants).

Large vessel occlusion mediated fluid attenuated inversion recovery signal intensity ratio is associated with stroke within 4.5 h

Introduction

The primary objective was to investigate the value of the fluid attenuated inversion recovery (FLAIR) signal intensity ratio (SIR) in identifying stroke within 4.5 h. The secondary objective was to ascertain whether large vessel occlusion (LVO) mediated the relationship between the SIR and stroke within 4.5 h.

Methods

We analyzed 633 acute stroke patients within 24 h of clear symptom onset. The SIR and DWI-FLAIR mismatch were evaluated. First, we determined whether demographic variables, vascular risk factors and LVO were related to stroke within 4.5 h with multivariate logistic regression analyses and stratified regression analysis. Next, we used mediation analysis to determine whether LVO explained the association between SIR and stroke within 4.5 h. Finally, we used receiver operating characteristic (ROC) analysis to assess the value of SIR, independent variable, and multiparameter models in identifying stroke within 4.5 h and compared with DWI-FLAIR mismatch.

Results

Hyperlipemia, LVO and SIR were associated with stroke within 4.5 h. Mediation analysis revealed that LVO partially mediated the relationship between SIR and stroke within 4.5 h (p < 0.001). The multiparameter model (hyperlipemia, LVO and SIR) showed significantly improved performance (AUC 0.869) in identifying stroke within 4.5 h over DWI-FLAIR mismatch (0.684), hyperlipemia (0.632), LVO (0.667) and SIR (0.773) models.

Conclusion

SIR is associated with stroke within 4.5 h, and LVO partially mediates this relationship. A multiparameter model combining hyperlipemia, LVO and SIR can more accurately identify stroke within 4.5 h than individual parameter models.

Correlation Between MMP9 Promoter Methylation and Transient Ischemic Attack/Mild Ischemic Stroke with Early Cognitive Impairment

Background/Objective

Dyskinesia caused by transient ischemic attack (TIA) and mild ischemic stroke (MIS) is mild and short-lived; however, cognitive impairment (CI) can occur in the acute phase and be easily overlooked. DNA methylation is an epigenetic phenomenon that can affect gene expression through gene silencing. Blood levels of matrix metalloproteinase (MMP) 9 are elevated in ischemic stroke patients and is associated with the destruction of the blood-brain barrier and the occurrence of CI. No studies have investigated the relationship between MMP9 gene methylation and TIA/MIS with early cognitive impairment (ECI). As such, the purpose of the present study was to investigate the correlation between MMP9 gene methylation and TIA/MIS with ECI.

Methods

Data from 112 subjects were collected, including 84 with TIA/MIS (National Institutes of Health Stroke Scale <5 points) and 28 non-stroke control subjects. Patients were evaluated within 7 days of TIA/MIS onset according to four single-domain cognitive scales. Whole blood DNA methylation was detected using MethylTarget sequencing technology. Comparison of MMP9 gene methylation levels among subgroups was performed using statistical methods.

Results

The site S33-79 in the TIA/MIS group was hypomethylated compared with the control group, and sites S33-25 and S33-30 in TIA/MIS with ECI was hypomethylated compared with TIA/MIS without ECI. Compared with the small artery occlusion group, MMP9 gene, S33-25, 30, 39, 53, 58, 73, 79, 113 and 131 sites in the large artery atherosclerosis group were hypomethylated.

Conclusion

MMP9 gene hypomethylation sites were associated with TIA/MIS and TIA/MIS with ECI, and there was a strong correlation between MMP9 gene hypomethylation and atherosclerotic TIA/MIS. MMP9 gene methylation can reflect the severity of TIA/MIS. MMP9 gene hypomethylation sites may be used as potential biomarkers and therapeutic targets for TIA/MIS and TIA/MIS with ECI.

Biomarkers Predictive of Long-Term Outcome After Ischemic Stroke: A Meta-Analysis

BACKGROUND AND PURPOSE

The goal of this study was to systematically review the utility of serum biomarkers in the setting of ischemic stroke (IS) to predict long-term outcome.

METHODS

A systematic literature review was performed using the PubMed and MEDLINE databases for studies published between 1986-2018. All studies assessing long-term functional outcome (defined as 30 days or greater) following IS with respect to serum biomarkers were included. Data were extracted and pooled using a meta-analysis of odds ratios.

RESULTS

Of the total 2928 articles in the original literature search, 183 studies were ultimately selected. A total of 127 serum biomarkers were included. Biomarkers were grouped into several categories: inflammatory (32), peptide/enzymatic (30), oxidative/metabolic (28), hormone/steroid based (23), and hematologic/vascular (14). The most commonly studied biomarkers in each category were found to be CRP, S100β, albumin, copeptin, and D-dimer. With the exception of S100β, all were found to be statistically associated with >30-day outcome after ischemic stroke.

CONCLUSIONS

Serum-based biomarkers have the potential to predict functional outcome in IS patients. This meta-analysis has identified CRP, albumin, copeptin, and D-dimer to be significantly associated with long-term outcome after IS. These biomarkers have the potential to serve as a platform for prognosticating stroke outcomes after 30 days. These serum biomarkers, some of which are routinely ordered, can be combined with imaging biomarkers and used in artificial intelligence algorithms to provide refined predictive outcomes after injury. Ultimately these tools will assist physicians in providing guidance to families with regards to long-term independence of patients.

Matrix metalloproteinase-9 as a messenger in the cross talk between obstructive sleep apnea and comorbid systemic hypertension, cardiac remodeling, and ischemic stroke: a literature review

STUDY OBJECTIVES

OSA is a common sleep disorder. There is a strong link between sleep-related breathing disorders and cardiovascular and cerebrovascular diseases. Matrix metalloproteinase-9 (MMP-9) is a biological marker for extracellular matrix degradation, which plays a significant role in systemic hypertension, myocardial infarction and postmyocardial infarction heart failure, and ischemic stroke. This article reviews MMP-9 as an inflammatory mediator and a potential messenger between OSA and OSA-induced comorbidities.

METHODS

We reviewed the MEDLINE database (PubMed) for publications on MMP-9, OSA, and cardiovascular disease, identifying 1,592 studies and including and reviewing 50 articles for this work.

RESULTS

There is strong evidence that MMP-9 and tissue inhibitor of metalloproteinase-1 levels are elevated in patients with OSA (mainly MMP-9), systemic hypertension, myocardial infarction, and postmyocardial infarction heart failure. Our study showed variable results that could be related to the sample size or to laboratory methodology.

CONCLUSIONS

MMP-9 and its endogenous inhibitor, tissue inhibitor of metalloproteinase-1, are a common denominator in OSA, systemic hypertension, myocardial infarction, and heart failure. This characterization makes MMP-9 a target for developing novel selective inhibitors that can serve as adjuvant therapy in patients with OSA, which may ameliorate the cardiovascular and cerebrovascular mortality associated with OSA.

Immune-inflammatory, coagulation, adhesion, and imaging biomarkers combined in machine learning models improve the prediction of death 1 year after ischemic stroke

Some clinical, imaging, and laboratory biomarkers have been identified as predictors of prognosis of acute ischemic stroke (IS). The aim of this study was to evaluate the prognostic validity of a combination of clinical, imaging, and laboratory biomarkers in predicting 1-year mortality of IS. We evaluated 103 patients with IS within 24 h of their hospital admission and assessed demographic data, IS severity using the National Institutes of Health Stroke Scale (NIHSS), carotid intima-media thickness (cIMT), and degree of stenosis, as well as laboratory variables including immune-inflammatory, coagulation, and endothelial dysfunction biomarkers. The IS patients were categorized as survivors and non-survivors 1 year after admission. Non-survivors showed higher NIHSS and cIMT values, lower antithrombin, Protein C, platelet counts, and albumin, and higher Factor VIII, von Willebrand Factor (vWF), white blood cells, tumor necrosis factor (TNF)-α, interleukin (IL)-10, high-sensitivity C-reactive protein (hsCRP), and vascular cellular adhesion molecule 1 (VCAM-1) than survivors. Neural network models separated non-survivors from survivors using NIHSS, cIMT, age, IL-6, TNF-α, hsCRP, Protein C, Protein S, vWF, and platelet endothelial cell adhesion molecule 1 (PECAM-1) with an area under the receiving operating characteristics curve (AUC/ROC) of 0.975, cross-validated accuracy of 93.3%, sensitivity of 100% and specificity of 85.7%. In conclusion, imaging, immune-inflammatory, and coagulation biomarkers add predictive information to the NIHSS clinical score and these biomarkers in combination may act as predictors of 1-year mortality after IS. An early prediction of IS outcome is important for personalized therapeutic strategies that may improve the outcome of IS.

Stroke prevention in patients with arterial hypertension: Recommendations of the Spanish Society of Neurology's Stroke Study Group

OBJECTIVE

To update the recommendations of the Spanish Society of Neurology on primary and secondary stroke prevention in patients with arterial hypertension.

DEVELOPMENT

We proposed several questions to identify practical issues for the management of blood pressure (BP) in stroke prevention, analysing the objectives of blood pressure control, which drugs are most appropriate in primary prevention, when antihypertensive treatment should be started after a stroke, what levels we should aim to achieve, and which drugs are most appropriate in secondary stroke prevention. We conducted a systematic review of the PubMed database and analysed the main clinical trials to address these questions and establish a series of recommendations.

CONCLUSIONS

In primary stroke prevention, antihypertensive treatment should be started in patients with BP levels >  140/90 mmHg, with a target BP of < 130/80 mmHg. In secondary stroke prevention, we recommend starting antihypertensive treatment after the acute phase (first 24 hours), with a target BP of < 130/80 mmHg. The use of angiotensin-II receptor antagonists or diuretics alone or in combination with angiotensin-converting enzyme inhibitors is preferable.

Biomarkers of Angiogenesis and Neuroplasticity as Promising Clinical Tools for Stroke Recovery Evaluation

Several key issues impact the clinical practice of stroke rehabilitation including a patient’s medical history, stroke experience, the potential for recovery, and the selection of the most effective type of therapy. Until clinicians have answers to these concerns, the treatment and rehabilitation are rather intuitive, with standard procedures carried out based on subjective estimations using clinical scales. Therefore, there is a need to find biomarkers that could predict brain recovery potential in stroke patients. This review aims to present the current state-of-the-art stroke recovery biomarkers that could be used in clinical practice. The revision of biochemical biomarkers has been developed based on stroke recovery processes: angiogenesis and neuroplasticity. This paper provides an overview of the biomarkers that are considered to be ready-to-use in clinical practice and others, considered as future tools. Furthermore, this review shows the utility of biomarkers in the development of the concept of personalized medicine. Enhancing brain neuroplasticity and rehabilitation facilitation are crucial concerns not only after stroke, but in all central nervous system diseases.

Matrix Metalloproteinase-9 Expression is Enhanced by Ischemia and Tissue Plasminogen Activator and Induces Hemorrhage, Disability and Mortality in Experimental Stroke

Matrix metalloproteinase-9 (MMP-9) degrades collagen and other cellular matrix proteins. After acute ischemic stroke, increased MMP-9 levels are correlated with hemorrhage, lack of reperfusion and stroke severity. Nevertheless, definitive data that MMP-9 itself causes poor outcomes in ischemic stroke are limited. In a model of experimental ischemic stroke with reperfusion, we examined whether ischemia and recombinant tissue plasminogen activator (r-tPA) therapy affected MMP-9 expression, and we used specific inhibitors to test if MMP-9 affects brain injury and recovery. After stroke, MMP-9 expression increased significantly in the ischemic vs. non-ischemic hemisphere of the brain (p < 0.001). MMP-9 expression in the ischemic, but not the non-ischemic hemisphere, was further increased by r-tPA treatment (p < 0.001). To determine whether MMP-9 expression contributed to stroke outcomes after r-tPA treatment, we tested three different antibody MMP-9 inhibitors. When compared to treatment with r-tPA and saline, treatment with r-tPA and MMP-9 antibody inhibitors significantly reduced brain hemorrhage by 11.3 to 38.6-fold (p < 0.01), brain swelling by 2.8 to 4.3-fold (p < 0.001) and brain infarction by 2.5 to 3.9-fold (p < 0.0001). Similarly, when compared to treatment with r-tPA and saline, treatment with r-tPA and an MMP-9 antibody inhibitor significantly improved neurobehavioral outcomes (p < 0.001), decreased weight loss (p < 0.001) and prolonged survival (p < 0.01). In summary, both prolonged ischemia and r-tPA selectively enhanced MMP-9 expression in the ischemic hemisphere. When administered with r-tPA, specific MMP-9 inhibitors markedly reduced brain hemorrhage, swelling, infarction, disability and death, which suggests that blocking the deleterious effects of MMP-9 may improve outcomes after ischemic stroke.

Association between serum matrix metalloproteinase-9 and poor prognosis in acute ischemic stroke patients: The role of dyslipidemia

BACKGROUND AND AIMS

Whether the prognostic value of matrix metalloproteinase-9 (MMP-9) is modified by patients' dyslipidemia status is unknown. The aim of present study was to evaluate the prognostic effect of MMP-9 among ischemic stroke patients stratified by dyslipidemia status.

METHODS AND RESULTS

MMP-9 levels were measured for 2977 acute ischemic stroke patients from 26 participating hospitals across China, and data of clinical outcomes within one year after ischemic stroke was collected. The primary outcome was a composite outcome of major disability and death at one year after stroke onset, and secondary outcomes were major disability, death, vascular events and recurrent stroke. The association between MMP-9 and primary outcome was appreciably modified by dyslipidemia status (P_interaction = 0.048). After multivariate adjustment, increased MMP-9 level was associated with increased risk of primary outcome at one year after ischemic stroke in the patients with dyslipidemia (odds ratio, 1.34; 95% confidence interval, 1.06-1.79), but not in those without dyslipidemia (odds ratio, 1.23; 95% confidence interval, 0.90-1.68). Increased MMP-9 was also significantly associated with major disability, death and vascular events in the patients with dyslipidemia but not in those without dyslipidemia (P for interaction < 0.05 for all).

CONCLUSION

Increased MMP-9 was associated with poor prognosis within one-year after stroke only in patients with dyslipidemia, suggesting that the prognostic value of MMP-9 be modified by dyslipidemia status of ischemic stroke patients. Further prospective study from other populations and randomized clinical trials are needed to verify our findings and clarify the potential mechanisms.

Association of Matrix Metalloproteinase 9 and Cellular Fibronectin and Outcome in Acute Ischemic Stroke: A Systematic Review and Meta-Analysis

Introduction: The role of matrix metalloproteinase 9 (MMP-9) and cellular fibronectin (c-Fn) in acute ischemic stroke is controversial. We systematically reviewed the literature to investigate the association of circulating MMP-9 and c-Fn levels and MMP-9 rs3918242 polymorphism with the risk of three outcome measures after stroke.

Methods: We searched English and Chinese databases to identify eligible studies. Outcomes included severe brain edema, hemorrhagic transformation, and poor outcome (modified Rankin scale score ≥3). We estimated standardized mean differences (SMDs) and pooled odds ratios (ORs) with 95% confidence intervals (CIs).

Results: Totally, 28 studies involving 7,239 patients were included in the analysis of circulating MMP-9 and c-Fn levels. Meta-analysis indicated higher levels of MMP-9 in patients with severe brain edema (SMD, 0.76; 95% CI, 0.18–1.35; four studies, 419 patients) and hemorrhagic transformation (SMD, 1.00; 95% CI, 0.41–1.59; 11 studies, 1,709 patients) but not poor outcome (SMD, 0.30; 95% CI, −0.12 to 0.72; four studies, 759 patients). Circulating c-Fn levels were also significantly higher in patients with severe brain edema (SMD, 1.55; 95% CI, 1.18–1.93; four studies, 419 patients), hemorrhagic transformation (SMD, 1.75; 95% CI, 0.72–2.78; four studies, 458 patients), and poor outcome (SMD, 0.46; 95% CI, 0.16–0.76; two studies, 210 patients). Meta-analysis of three studies indicated that the MMP-9 rs3918242 polymorphism may be associated with hemorrhagic transformation susceptibility under the dominant model (TT + CT vs. CC: OR, 0.621; 95% CI, 0.424–0.908; P = 0.014). No studies reported the association between MMP-9 rs3918242 polymorphism and brain edema or functional outcome after acute stroke.

Conclusion: Our meta-analysis showed that higher MMP-9 levels were seen in stroke patients with severe brain edema and hemorrhagic transformation but not poor outcome. Circulating c-Fn levels appear to be associated with all three outcomes including severe brain edema, hemorrhagic transformation, and poor functional outcome. The C-to-T transition at the MMP-9 rs3918242 gene appears to reduce the risk of hemorrhagic transformation.

Stroke prevention in patients with arterial hypertension: Recommendations of the Spanish Society of Neurology's Stroke Study Group

OBJECTIVE

To update the recommendations of the Spanish Society of Neurology on primary and secondary stroke prevention in patients with arterial hypertension.

DEVELOPMENT

We proposed several questions to identify practical issues for the management of blood pressure (BP) in stroke prevention, analysing the objectives of blood pressure control, which drugs are most appropriate in primary prevention, when antihypertensive treatment should be started after a stroke, what levels we should aim to achieve, and which drugs are most appropriate in secondary stroke prevention. We conducted a systematic review of the PubMed database and analysed the main clinical trials to address these questions and establish a series of recommendations.

CONCLUSIONS

In primary stroke prevention, antihypertensive treatment should be started in patients with BP levels >140/90mmHg, with a target BP of <130/80mmHg. In secondary stroke prevention, we recommend starting antihypertensive treatment after the acute phase (first 24hours), with a target BP of <130/80mmHg. The use of angiotensin-II receptor antagonists or diuretics alone or in combination with angiotensin-converting enzyme inhibitors is preferable.

Evaluation of inflammatory markers and mean platelet volume as short-term outcome indicators in young adults with ischemic stroke

Background

Studying outcome predictors in patients with onset of cerebral infarction in early adult life may enhance our knowledge of disease pathophysiology and prognosis.

Aim

The aim is to identify independent predictors of short-term outcome of first-ever ischemic stroke in young adults with special emphasis on inflammatory and thrombogenic markers.

Methods

We enrolled 33 patients aged 19–44 years with first-ever ischemic stroke admitted to Kasr Alainy Stroke Unit and 33 matched controls. Clinical, radiological, and laboratory (adhesion molecules, C-reactive protein, prolactin, and mean platelet volume) evaluations were carried out. Functional outcome at 7 days after stroke onset was assessed using the modified Rankin scale, and independent predictors were identified.

Results

The most frequently identified risk factor was cardiac abnormality. Patients exhibited significantly higher levels of baseline inflammatory and thrombogenic markers compared with controls. These markers were significantly correlated with the stroke severity. Logistic regression model showed that high National Institutes of Health Stroke Scale (NIHSS) score (odds ratios [OR] = 0.13; 95% confidence interval [CI], 0.04–0.24; P = 0.01) and large infarction size (OR = 0.11; 95% CI, 0.09–0.17; P = 0.04) but not the laboratory markers were independent predictors of unfavorable outcome.

Conclusion

Our data suggested that higher NIHSS scores and large infarction size served as independent predictors of short-term unfavorable outcome, while inflammatory and thrombogenic markers did not.

Plasma levels of matrix metalloproteinase-9: A possible marker for cold-induced stroke risk in hypertensive rats

The cold weather is associated with an increased occurrence of acute stroke events. However, the underlying mechanisms have not yet been fully elucidated. In the present study, we investigated whether plasma matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) levels as well as the MMP-9/TIMP-1 ratio could be used as predictor for cold-induced stroke risk in hypertensive rats. A total of 50 male rats were subjected to either control group or 2-kidney, 2-clip (2K - 2C) group (N = 25, each), After blood pressure was stabilized, rats were placed in an intelligent artificial climate chamber and maintained on a 12-h light (22 °C)/dark (4 °C) cycle for 3 days. Plasma levels of MMP-9 and TIMP-1 were measured before and after cold exposure from 50 rats by ELISA. Pretreatment plasma MMP-9 levels were significantly higher in 2K-2C rats than in the controls (P <  0.05), TIMP-1 levels were significantly lower in 2K-2C rats than in the controls (P <  0.05), pretreatment plasma MMP-9 levels were significantly higher in those with cold-induced stroke compared to those without (P <  0.05). Logistic regression analysis showed that only plasma MMP-9 levels remained independently associated with cold-induced stroke after adjusting for potential confounders (OR, 1.17; 95% CI, 1.08 to 1.32; P < 0.007). In contrast, no correlation was observed between systolic blood pressure (SBP), TIMP-1 or MMP-9/TIMP-1 ratio and the cold-induced stroke. Higher plasma MMP-9 levels are significantly correlated with cold-induced stroke in hypertensive rats treated with intermittent cold stress. Plasma MMP-9 may be as a promising biomarker to predict the risk of cold-induced stroke events in hypertensive rats.

Management of Blood Pressure After Acute Ischemic Stroke

PURPOSE OF REVIEW

The present manuscript examines the significance of blood pressure elevation in patients with acute ischemic stroke, the physiologic principles worthy of consideration during its treatment, and the recent empirical evidence that should guide management protocols. It also provides a sound and practical approach to treatment along the time continuum, with particular relevance to reperfusion strategies.

RECENT FINDINGS

The existing evidence shows that both insufficient and excessive blood pressures are detrimental to the outcome of patients with acute ischemic stroke. This "U-shaped" relation, however, relates to measurements at the time of presentation, and clinical studies lack detail and specificity relative to differential measurements along the time continuum, particularly prior to and following reperfusion. Extrapolating from recent series, it is possible to construct treatment protocols balanced for effectiveness and safety. The management of blood pressure after acute ischemic stroke is an important, complex, and challenging aspect of care, requiring a thorough understanding of cerebrovascular physiology. Along the time continuum, the therapeutic priorities start with the preservation of penumbral tissue prior to reperfusion and then follow with the limitation of the damaging effects of excessive blood pressure readings after reperfusion, optimizing the chances of improved outcomes.

Serum level of macrophage migration inhibitory factor predicts severity and prognosis in patients with ischemic stroke

OBJECTIVE

To evaluate whether the macrophage migration inhibitory factor (MIF) level in serum of ischemic stroke patients was associated with their clinical severity and early outcome.

METHODS

During February 2017-March 2018, consecutive patients admitted to our hospital because of first-ever ischemic stroke were identified. The prognostic value of MIF was set for predicting the outcome of these patients at discharge. The results were compared with existing methods, including National Institutes of Health Stroke Scale (NIHSS) score and validated indicators.

RESULTS

289 patients were enrolled. The serum level of all patients was determined (median: 20.6 ng/ml). At admission, 131 patients (45.3%) were evaluated as minor stroke (NIHSS < 5). When serum level of MIF was increased by each 1 ng/ml, the unadjusted and adjusted risk of moderate-to-high clinical severity was elevated by 5% (OR = 1.05 [95% CI: 1.01-1.09], P = 0.006) and 3% (1.03 [1.00-1.08], P = 0.02), respectively. At discharge, 82 patients (28.4%) had poor functional outcomes. The median serum level of MIF was lower in group with good outcomes than that observed in poor outcomes (19.4[15.8-24.2] vs. 24.0[19.9-29.4] ng/ml; P < 0.001). When serum level of MIF was increased by each 1 ng/ml, the unadjusted and adjusted risk of poor outcomes was elevated by 9% (1.09 [1.05-1.13], P < 0.001) and 6% (1.06 [1.02-1.10], P < 0.01), respectively.

CONCLUSIONS

High MIF levels are independently related to the moderate to high clinical severity in ischemic stroke patients, as well as the poor outcome at discharge.

Inflammatory molecules might become both biomarkers and therapeutic targets for stroke management

Stroke is the fifth leading cause of death and the most frequent cause of disability worldwide. Currently, stroke diagnosis is based on neuroimaging; therefore, the lack of a rapid tool to diagnose stroke is still a major concern. In addition, therapeutic approaches to combat ischemic stroke are still scarce, since the only approved therapies are directed toward restoring blood flow to the affected brain area. However, due to the reduced time window during which these therapies are effective, few patients benefit from them; therefore, alternative treatments are urgently needed to reduce stroke brain damage in order to improve patients' outcome. The inflammatory response triggered after the ischemic event plays an important role in the progression of stroke; consequently, the study of inflammatory molecules in the acute phase of stroke has attracted increasing interest in recent decades. Here, we provide an overview of the inflammatory processes occurring during ischemic stroke, as well as the potential for these inflammatory molecules to become stroke biomarkers and the possibility that these candidates will become interesting neuroprotective therapeutic targets to be blocked or stimulated in order to modulate inflammation after stroke.

Serum matrix metalloproteinase-9 levels and prognosis of acute ischemic stroke

OBJECTIVE

To examine the association between serum matrix metalloproteinases-9 (MMP-9) levels and prognosis of acute ischemic stroke.

METHODS

We measured serum MMP-9 levels in 3,186 participants (2,008 men and 1,178 women) from the China Antihypertensive Trial in Acute Ischemic Stroke (CATIS). Study outcome data on death, major disability (modified Rankin Scale score ≥3), and vascular disease were collected at 3 months after stroke onset.

RESULTS

During 3 months of follow-up, 767 participants (24.6%) experienced major disability or died. Serum MMP-9 was significantly associated with an increased risk of death and major disability after adjustment for age, sex, time from onset to randomization, current smoking, alcohol drinking, admission NIH Stroke Scale score, diastolic blood pressure, plasma glucose, white blood cell counts, use of antihypertensive medications, and history of hypertension, coronary heart disease, and diabetes mellitus. For example, 1-SD (0.32 ng/mL) higher log-MMP-9 was associated with an odds ratio (95% confidence interval) of 1.16 (1.06-1.28) for the combined outcome of death and major disability, 1.12 (1.01-1.23) for major disability, and 1.29 (1.01-1.66) for death. The addition of serum MMP-9 to conventional risk factors improved risk prediction of the combined outcome of death or major disability (net reclassification index 9.1%, p = 0.033; integrated discrimination improvement 0.4%, p = 0.004).

CONCLUSIONS

Higher serum MMP-9 levels in the acute phase of ischemic stroke were associated with increased risk of mortality and major disability, suggesting that serum MMP-9 could be an important prognostic factor for ischemic stroke.

Role of Brain Biomarker in Predicting Clinical Outcome in Hypertensive Cerebrovascular Ischemic Stroke

This study was undertaken to evaluate the role of serum neuron specific enolase (NSE) in prediction of disability and neurological worsening in hypertensive ischemic cerebrovascular stroke. 80 hypertensive ischemic stroke patients diagnosed by a neurologist as per WHO definition along with radiological findings suggestive of cerebrovascular stroke and differentiating from hemorrhagic stroke and 60 controls having essential hypertension coming to hospital because of regular checkup or headache but with no neurological disease were included in the study. Neurological disability was assessed by NIHSS at the time of admission (within 72 h from the onset of stroke) and on 7th day after admission and cases were categorized into mild, moderate and severe disability. Venous blood samples were drawn within 72 h from the onset of symptoms. The samples were processed as per the laboratory protocol. The serum NSE samples were analyzed using an enzyme immunoassay based on the sandwich technique. We observed raised serum NSE in hypertensive ischemic stroke (17.4 ± 5.4 ng/ml) with significant association between different hypertensive groups than in hypertensive controls (9.1 ± 0.75 ng/ml). Greater degree of disability was observed in hypertensive stroke patients with raised serum NSE and hypertensive patients with mean serum NSE level of 22.9 ± 3.6 ng/ml and dyslipidemia had greater probability of neurological worsening as compared to those with mean serum NSE level of 12.7 ± 1.2 ng/ml. Serum NSE levels can serve as a peripheral indicator of neuronal damage and assist in the prediction of disability and clinical outcome in hypertensive cerebrovascular ischemic stroke patients.

The role of the lectin-like oxLDL receptor (LOX-1) in traffic-generated air pollution exposure-mediated alteration of the brain microvasculature in Apolipoprotein (Apo) E knockout mice

Recent studies have shown a strong correlation between air pollution-exposure and detrimental outcomes in the central nervous system, including alterations in blood brain barrier (BBB) integrity, neuroinflammation, and neurodegeneration. However, the mechanisms mediating these pathologies have not yet been fully elucidated. We have previously reported that exposure to traffic-generated air pollution results in increased circulating oxidized low-density lipoprotein (oxLDL), associated with alterations in BBB integrity, in atherosclerotic Apolipoprotein E null (ApoE-/-) mice. Thus, we investigated the role of the lectin-like oxLDL receptor (LOX)-1 in mediating these deleterious effects in ApoE-/- mice exposed to a mixture of gasoline and diesel engine exhaust (MVE: 100 PM µg/m3) for 6 h/d, 7d/week, for 30 d by inhalation. Concurrent with exposures, a subset of mice were treated with neutralizing antibodies to LOX-1 (LOX-1 Ab) i.p., or IgG (control) i.p., every other day during exposures. Resulting brain microvascular integrity, tight junction (TJ) protein expression, matrix metalloproteinase (MMP)-9/-2 activity, ROS, and markers of cellular adhesion and monocyte/macrophage sequestration were assessed. MVE-exposure resulted in decreased BBB integrity and alterations in microvascular TJ protein expression, associated with increased LOX-1 expression, MMP-9/-2 activities, and lipid peroxidation, each of which was attenuated with LOX-1 Ab treatment. Furthermore, MVE-exposure induced cerebral microvascular ROS and adhesion molecules, expression of which was not normalized through LOX-1 Ab-treatment. Such findings suggest that alterations in brain microvascular structure and integrity observed with MVE-exposure may be mediated, at least in part, via LOX-1 signaling.

Blood/Brain Biomarkers of Inflammation After Stroke and Their Association With Outcome: From C-Reactive Protein to Damage-Associated Molecular Patterns

Stroke represents one of the most important causes of disability and death in developed countries. However, there is a lack of prognostic tools in clinical practice to monitor the neurological condition and predict the final outcome. Blood biomarkers have been proposed and studied in this indication; however, no biomarker is currently used in clinical practice. The stroke-related neuroinflammatory processes have been associated with a poor outcome in stroke, as well as with poststroke complications. In this review, we focus on the most studied blood biomarkers of this inflammatory processes, cytokines, and C-reactive protein, evaluating its association with outcome and complications in stroke through the literature, and performing a systematic review on the association of C-reactive protein and functional outcome after stroke. Globally, we identified uncertainty with regard to the association of the evaluated biomarkers with stroke outcome, with little added value on top of clinical predictors such as age or stroke severity, which makes its implementation unlikely in clinical practice for global outcome prediction. Regarding poststroke complications, despite being more practical scenarios in which to make medical decisions following a biomarker prediction, not many studies have been performed, although there are now some candidates for prediction of poststroke infections. Finally, as potential new candidates, we reviewed the pathophysiological actions of damage-associated molecular patterns as triggers of the neuroinflammatory cascade of stroke, and their possible use as biomarkers.

The relationship of pro-inflammatory markers to vascular endothelial function after acute stroke

Purpose/Aim: Data from chronic stroke studies have reported reduced blood flow and vascular endothelial function in the stroke-affected limb. It is unclear whether these differences are present early after stroke. First, we investigated whether vascular endothelial function in the stroke-affected limb would be different from healthy adults. Second, we examined whether between-limb differences in vascular endothelial function existed in the stroke-affected arm compared to the non-affected arm. Last, we tested whether reduced vascular endothelial function was related to pro-inflammatory markers that are present early after stroke.

MATERIALS AND METHODS

Vascular endothelial function was assessed by flow-mediated dilation (FMD) in the brachial artery within 72 h post-stroke. All participants withheld medications from midnight until after the procedure. Ultrasound scans and blood draws for pro-inflammatory markers occurred on the same day between 7:30 am and 9:00 am.

RESULTS

People with acute stroke had significantly lower FMD (4.2% ± 4.6%) than control participants (8.5% ± 5.2%, p = 0.037). Stroke participants had between-limb differences in FMD (4.2% ± 4.6% stroke-affected vs. 5.3% ± 4.4% non-affected, p = 0.02), whereas, the control participants did not. Of the pro-inflammatory markers, only vascular cell adhesion molecule-1(VCAM-1) had a significant relationship to FMD (stroke-affected limb, r = -0.62, p = 0.03; non-affected limb, r = -0.75, p = 0.005), but not tumor necrosis factor alpha nor interleukin-6.

CONCLUSIONS

Vascular endothelial function is reduced starting in the early stage of stroke recovery. People with higher levels of VCAM-1 had a lower FMD response.

Implications of MMP9 for Blood Brain Barrier Disruption and Hemorrhagic Transformation Following Ischemic Stroke

Numerous studies have documented increases in matrix metalloproteinases (MMPs), specifically MMP-9 levels following stroke, with such perturbations associated with disruption of the blood brain barrier (BBB), increased risk of hemorrhagic complications, and worsened outcome. Despite this, controversy remains as to which cells release MMP-9 at the normal and pathological BBB, with even less clarity in the context of stroke. This may be further complicated by the influence of tissue plasminogen activator (tPA) treatment. The aim of the present review is to examine the relationship between neutrophils, MMP-9 and tPA following ischemic stroke to elucidate which cells are responsible for the increases in MMP-9 and resultant barrier changes and hemorrhage observed following stroke.

Prognostic value of blood interleukin-6 in the prediction of functional outcome after stroke: a systematic review and meta-analysis

We aimed to quantify the association of blood interleukin-6 (IL-6) concentrations with poor outcome after stroke and its added predictive value over clinical information. Meta-analysis of 24 studies confirmed this association with a weighted mean difference of 3.443 (1.592-5.294) pg/mL, despite high heterogeneity and publication bias. Individual participant data including 4112 stroke patients showed standardized IL-6 levels in the 4th quartile were independently associated with poor outcome (OR=2.346 (1.814-3.033), p<0.0001). However, the additional predictive value of IL-6 was moderate (IDI=1.5%, NRI=5.35%). Overall these results indicate an unlikely translation of IL-6 into clinical practice for this purpose.

Impact of collaterals on successful revascularization in Solitaire FR with the intention for thrombectomy

BACKGROUND AND PURPOSE

Collaterals at angiography before endovascular therapy were analyzed to ascertain the effect on a novel end point of successful revascularization without symptomatic hemorrhage in the Solitaire FR With the Intention for Thrombectomy (SWIFT) study.

METHODS

Collateral grade (American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology) on baseline angiography was independently assessed, blind to other data, with statistical analyses delineating the relationship with clinical, laboratory, and imaging parameters.

RESULTS

Angiographic data on collaterals were available in 119 of 144 subjects (mean age, 67±12 years; 52% woman; median National Institutes of Health Stroke Scale, 18 [range, 8-28]). Worse collaterals were noted in subjects with elevated baseline blood glucose (P=0.013) and those with elevated baseline systolic blood pressure (P=0.039). Multivariate predictors of partial or worse collaterals included absence of prior hypertension (odds ratio, 4.049, P=0.012), smoking history (odds ratio, 3.822; P=0.013), and higher blood glucose (odds ratio, 1.017; P=0.022). Collaterals were strongly related to Alberta Stroke Program Early CT Score (ASPECTS) at baseline (0-1: median 8 [3-10]; 2-9 [5-10]; 3-9 [7-10]; 4-9 [8-10]; P<0.001) and 24 hours (0-1: median 1 [0-5]; 2-6 [0-10]; 3-8 [0-10]; 4-8 [4-8]; P<0.001). Better collaterals were linked with Thrombolysis in Cerebral Infarction 2b/3 reperfusion (P=0.019), better median National Institutes of Health Stroke Scale at day 7/discharge (P<0.001), and better day 90 modified Rankin Scale (P<0.001). Better collateral grade was associated with successful revascularization without symptomatic hemorrhage, mean 2.3 (95% confidence interval, 2.1-2.5) versus 1.9 (95% confidence interval, 1.7-2.2), P=0.021.

CONCLUSIONS

Better collaterals were associated with lower glucose, lower blood pressure, smaller baseline infarcts in SWIFT, and greater likelihood of successful revascularization without hemorrhage and good clinical outcomes.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT01054560.

HbA1c is associated with increased all-cause mortality in the first year after acute ischemic stroke

OBJECTIVES

To assess the association between baseline HbA1c and the poor outcomes within 1 year after acute ischemic stroke.

METHODS

Acute ischemic stroke patients with HbA1c values at baseline (n  =  2186) were selected from the abnormal glucose regulation in patients with acute stroke across China study (ACROSS). Logistic regressions were performed to assess the association between HbA1c quartiles (<5.5% [37 mmol/mol], 5.5 to <6.1% [37 to <43 mmol/mol], 6.1 to <7.2% [43 to <55 mmol/mol], and ≥ 7.2% [≥ 55 mmol/mol]) and the poor outcomes within 1 year. Poor outcomes were defined as all-cause mortality (modified Rankin scale [mRS]  =  6) and poor functional outcome (mRS [2-6]).

RESULTS

The risk for all-cause mortality was significantly increased in HbA1c level >5.5% [>37 mmol/mol] when compared to HbA1c quartile <5.5% [<37 mmol/mol] and dramatically increased to two to three times higher in the highest HbA1c quartile ≥ 7.2% [>55 mmol/mol] (1-year all-cause mortality model, odds ratios [ORs] were 1.07, 1.01, and 2.45, P for trend 0.009). After the further analysis with previous diabetes mellitus (DM) and post-stroke insulin use stratified, the risk of mortality was increased across the HbA1c levels (P for trend 0.020) and dramatically augmented in HbA1c ≥ 7.2% [>55 mmol/mol] in patients without a history of DM and without post-stroke insulin use.

DISCUSSION

Elevated HbA1c (from 5.5% [37 mmol/mol]) presenting pre-stroke glycemia status has a significant trend in increasing the risk of 1-year all-cause mortality. HbA1c ≥ 7.2% (>55 mmol/mol) is an independent risk predictor for 1-year all-cause mortality after acute first-ever ischemic stroke. Such an association might be altered by glycometabolism status.

Low serum n-3 polyunsaturated fatty acid/n-6 polyunsaturated fatty acid ratio predicts neurological deterioration in Japanese patients with acute ischemic stroke

BACKGROUND

Epidemiological and clinical trials have shown that n-3 polyunsaturated fatty acids (PUFAs) reduce the incidence of coronary heart disease or stroke. However, the association between PUFAs and acute-phase stroke has not yet been thoroughly studied. We investigated the impact of serum PUFAs on early neurological deterioration (END) in patients with acute ischemic stroke.

METHODS

In this retrospective study, we enrolled 281 Japanese patients (mean age: 75 ± 13 years; 165 males) with acute ischemic stroke diagnosed within 24 h of onset. General blood examinations, including PUFAs (n-3 PUFAs: eicosapentaenoic acid, EPA, and docosahexaenoic acid, DHA, and n-6 PUFAs: arachidonic acid, AA), were performed on admission. Other risk factors and comorbidities were also examined. END was defined as a ≥2-point increase in the National Institutes of Health Stroke Scale (NIHSS) score within a 72-hour period. Statistical significance between the END and non-END group was assessed using Wilcoxon rank sum tests or Student's t tests for categorical variables. Multiple logistic regression analyses were performed to identify predictors of END.

RESULTS

END was observed in 75 patients (26.7%). Diabetes mellitus (p = 0.003), high-sensitivity C-reactive protein (hs-CRP) level (p < 0.001), prior stroke (p = 0.035), ischemic heart disease (p = 0.029), EPA/AA ratio (p = 0.003), DHA/AA ratio (p = 0.002), EPA+DHA/AA ratio (p = 0.002), diagnosis of small vessel disease (p = 0.004) and admission NIHSS score (p < 0.001) were significantly associated with END. We used separate multiple logistic regression analyses for the EPA/AA, DHA/AA and EPA+DHA/AA ratios, because EPA and DHA are considered covariant factors (r = 0.544; p < 0.0001). Multiple logistic regression analyses showed that END was positively associated with diabetes mellitus, hs-CRP level and NIHSS score on admission, and negatively associated with the EPA/AA ratio (odds ratio, OR: 0.18; 95% confidence interval, CI: 0.05-0.58; p = 0.003), DHA/AA ratio (OR: 0.045; 95% CI: 0.006-0.30; p = 0.001), EPA+DHA/AA ratio (OR: 0.45; 95% CI: 0.26-0.74; p = 0.002) and diagnosis of small vessel disease.

CONCLUSIONS

Our data suggest that a low serum n-3 PUFA/n-6 PUFA ratio on admission may predict neurological deterioration in Japanese patients with acute ischemic stroke. Large-scale prospective studies are further required to clarify the role of PUFAs in the acute phase of ischemic stroke.

Predictive value of circulating interleukin-6 and heart-type fatty acid binding protein for three months clinical outcome in acute cerebral infarction: multiple blood markers profiling study

Introduction

There is no single blood marker for predicting the prognosis in ischemic stroke. A combination of multiple blood markers may enhance the ability to predict long-term outcome following ischemic stroke.

Methods

Blood concentrations of neuronal markers (neuron-specific enolase, visinin-like protein 1, heart type fatty acid binding protein (hFABP) and neuroglobin), astroglial markers (S100B and glial fibrillary acidic protein), inflammatory markers (IL-6, TNF-α, and C-reactive protein), blood-brain barrier marker (matrix metalloproteinase 9), and haemostatic markers (D-dimer and PAI-1) were measured within 24 hours after stroke onset. The discrimination and reclassification for favorable and poor outcome were compared after adding individual or a combination of blood markers to the clinical model of stroke outcome.

Results

In multivariate analysis, natural log-transformed (_log) IL-6 (odds ratio (OR): 1.75, 95% CI: 1.25 to 2.25, P = 0.001) and _loghFABP (OR: 3.23, 95% CI: 1.44 to 7.27, P = 0.005) were independently associated with poor outcome. The addition of a single blood marker to the clinical model did not improve the discriminating ability of the clinical model of stroke outcome. However, the addition of the combination of _logIL-6 and _loghFABP to the clinical model showed improved discrimination (area under receiver operating characteristic (AUROC) curve: 0.939 versus 0.910, P = 0.03) and reclassification performance (net reclassification improvement index: 0.18, P = 0.005).

Conclusions

A combination of circulating IL-6 and hFABP level has an additive clinical value for the prediction of stroke outcome.

Blood microRNAs in low or no risk ischemic stroke patients

Ischemic stroke is a multi-factorial disease where some patients present themselves with little or no risk factors. Blood microRNA expression profiles are becoming useful in the diagnosis and prognosis of human diseases. We therefore investigated the blood microRNA profiles in young stroke patients who presented with minimal or absence of risk factors for stroke such as type 2 diabetes, dyslipidemia and hypertension. Blood microRNA profiles from these patients varied with stroke subtypes as well as different functional outcomes (based on modified Rankin Score). These microRNAs have been shown to target genes that are involved in stroke pathogenesis. The findings from our study suggest that molecular mechanisms in stroke pathogenesis involving low or no risk ischemic stroke patients could differ substantially from those with pre-existing risk factors.

Towards the identification of blood biomarkers for acute stroke in humans: a comprehensive systematic review

AIMS

Identification of biomarkers for stroke will aid our understanding of its aetiology, provide diagnostic and prognostic indicators for patient selection and stratification, and play a significant role in developing personalized medicine. We undertook the largest systematic review conducted to date in an attempt to characterize diagnostic and prognostic biomarkers in acute ischaemic and haemorrhagic stroke and those likely to predict complications following thrombolysis.

METHODS

A comprehensive literature search was carried out to identify diagnostic and prognostic stroke blood biomarkers. Mean differences (MDs) and 95% confidence intervals (CIs) were calculated for each biomarker.

RESULTS

We identified a total of 141 relevant studies, interrogating 136 different biomarkers. Three biomarkers (C-reactive protein, P-selectin and homocysteine) significantly differentiated between ischaemic stroke and healthy control subjects. Furthermore, glial fibrillary acidic protein levels were significantly different between haemorrhagic stroke and ischaemic stroke patients (MD 224.58 ng l⁻¹; 95% CI 25.84, 423.32; P= 0.03), high levels of admission glucose were a strong predictor of poor prognosis after ischaemic stroke and symptomatic intracerebral haemorrhage post-thrombolysis, glutamate was found to be an indicator of progressive (unstable) stroke (MD 172.65 µmol l⁻¹, 95% CI 130.54, 214.75; P= 0.00001), D-dimer predicted in-hospital death (MD 0.67 µg ml⁻¹, 95% CI 0.35, 1.00; P= 0.0001), and high fibrinogen levels were associated with poor outcome at 3 months (MD 47.90 mg l⁻¹, 95% CI 14.88, 80.93; P= 0.004) following ischaemic stroke.

CONCLUSIONS

Few biomarkers currently investigated have meaningful clinical value. Admission glucose may be a strong marker of poor prognosis following acute thrombolytic treatment. However, molecules released in the bloodstream before, during or after stroke may have potential to be translated into sensitive blood-based tests.

Spontaneously hypertensive rats display reduced microglial activation in response to ischemic stroke and lipopolysaccharide

Background

For successful translation to clinical stroke studies, the Stroke Therapy Academic Industry Round Table criteria have been proposed. Two important criteria are testing of therapeutic interventions in conscious animals and the presence of a co-morbidity factor. We chose to work with hypertensive rats since hypertension is an important modifiable risk factor for stroke and influences the clinical outcome. We aimed to compare the susceptibility to ischemia in hypertensive rats with those in normotensive controls in a rat model for induction of ischemic stroke in conscious animals.

Methods

The vasoconstrictor endothelin-1 was stereotactically applied in the vicinity of the middle cerebral artery of control Wistar Kyoto rats (WKYRs) and Spontaneously Hypertensive rats (SHRs) to induce a transient decrease in striatal blood flow, which was measured by the Laser Doppler technique. Infarct size was assessed histologically by Cresyl Violet staining. Sensory-motor functions were measured at several time points using the Neurological Deficit Score. Activation of microglia and astrocytes in the striatum and cortex was investigated by immunohistochemistry using antibodies against CD68/Iba-1 and glial fibrillary acidic protein.

Results and conclusions

The SHRs showed significantly larger infarct volumes and more pronounced sensory-motor deficits, compared to the WKYRs at 24 h after the insult. However, both differences disappeared between 24 and 72 h. In SHRs, microglia were less susceptible to activation by lipopolysaccharide and there was a reduced microglial activation after induction of ischemic stroke. These quantitative and qualitative differences may be relevant for studying the efficacy of new treatments for stroke in accordance to the Stroke Therapy Academic Industry Round Table criteria.

A biochemical marker panel in MRI-proven hyperacute ischemic stroke-a prospective study

Background

Computer tomography (CT) is still the fastest and most robust technique to rule out ICH in acute stroke. However CT-sensitivity for detection of ischemic stroke in the hyperacute phase is still relatively low. Moreover the validity of pure clinical judgment is diminished by several stroke imitating diseases (mimics). The "Triage^® Stroke Panel", a biochemical multimarker assay, detects Brain Natriuretic Peptide (BNP), D-Dimers (DD), Matrix-Metalloproteinase-9 (MMP-9), and S100B protein and promptly generates a Multimarkerindex of these values (MMX). This index has been licensed for diagnostic purposes as it might increase the validity of the clinical diagnosis to differentiate between stroke imitating diseases and true ischemic strokes. Our aim was to prove whether the panel is a reliable indicating device for the diagnosis of ischemic stroke in a time window of 6 h to fasten the pre- and intrahospital pathway to fibrinolysis.

Methods

We investigated all consecutive patients admitted to our stroke unit during a time period of 5 months. Only patients with clinical investigation, blood sample collection and MRI within six hours from symptom onset were included. Values of biochemical markers were analyzed according to the results of diffusion weighted MR-imaging. In addition MMX-values in ischemic strokes were correlated with the TOAST-criteria. For statistical analysis the SAS Analyst software was used. Correlation coefficients were analyzed and comparison tests for two or more groups were performed. Statistical significance was assumed in case of p < 0.05. Finally a ROC-analysis was performed for the MMX-Index.

Results

In total 174 patients were included into this study (n = 100 strokes, n = 49 mimics, n = 25 transitoric ischemic attacks). In patients with ischemic strokes the mean NIHSS was 7.6 ± 6.2, while the mean DWI-lesion volume was 20.6 ml (range 186.9 to 4.2 ml). According to the MMX or the individual markers there was no statistically significant difference between the group of ischemic strokes and the group of mimics. Moreover the correlation of the index and the DWI-lesion-volume was poor (p = 0.2).

Conclusions

In our setting of acute MRI-proven ischemic stroke the used multimarker-assay (Triage^® Stroke Panel) was not of diagnostic validity. We do not recommend to perform this assay as this might lead to a unjustified time delay.

Reduced cardiorespiratory fitness after stroke: biological consequences and exercise-induced adaptations

Evidence from several studies consistently shows decline in cardiorespiratory (CR) fitness and physical function after disabling stroke. The broader implications of such a decline to general health may be partially understood through negative poststroke physiologic adaptations such as unilateral muscle fiber type shifts, impaired hemodynamic function, and decrements in systemic metabolic status. These physiologic changes also interrelate with reductions in activities of daily living (ADLs), community ambulation, and exercise tolerance, causing a perpetual cycle of worsening disability and deteriorating health. Fortunately, initial evidence suggests that stroke participants retain the capacity to adapt physiologically to an exercise training stimulus. However, despite this evidence, exercise as a therapeutic intervention continues to be clinically underutilized in the general stroke population. Far more research is needed to fully comprehend the consequences of and remedies for CR fitness impairments after stroke. The purpose of this brief review is to describe some of what is currently known about the physiological consequences of CR fitness decline after stroke. Additionally, there is an overview of the evidence supporting exercise interventions for improving CR fitness, and associated aspects of general health in this population.

IL-6 as a biomarker of ischemic cerebrovascular disease

The lack of a rapid and clinically accurate diagnostic tool remains a major obstacle to optimal care of patients with stroke. Cytokine changes in patients with acute stroke have been insufficiently studied. The purpose of this study is to delineate the relevance of IL-6 as a biochemical marker of stroke diagnosis, taking into account the genetic basis, and changes of the protein in serum and cerebrospinal fluid in relation to stroke development. Inflammation has an important role in ischemic cerebrovascular disease pathophysiology. Proinflammatory cytokines, such as IL-6, have been implicated in several mechanisms that might promote ischemic brain injury and an early neurological worsening. Cardiovascular diseases constitute one of the principal health problems in developing countries. Over the past few years, several studies have found evidence of the important role of inflammation in the ischemic cerebrovascular disease. The availability of a diagnostic biomarker panel for patients with stroke symptoms would be enormously valuable to complement clinical data and to precede radiological findings. IL-6 levels in cerebrospinal fluid and serum seem to reflect either the extent of tissue damage, or the accompanying clinical worsening. The -174 G/C functional polymorphism in the IL-6 gene might not be solely involved in disease susceptibility but also in linkage disequilibrium with other functional polymorphisms. Further studies are needed to solve this. Presently, the association between IL-6 genotype and stroke remains undetermined. Development of new neuroprotective therapies targeted to modulate cytokine-induced inflammation could be a promising way to prevent early deterioration in acute ischemic stroke.

Management of hypertension in acute stroke

Hypertension is commonly seen in the setting of an acute stroke. Although hypertension is the most important modifiable risk factor for both ischemic and hemorrhagic stroke, the immediate management of elevated blood pressure in this setting is controversial. Questions remain to be definitively answered, such as when to start lowering blood pressure, by how much to lower pressure, which pharmaceutical agents to use and whether to continue or stop previous antihypertensive medications. Recently, pilot studies have been initiated in an attempt to answer these questions and will hopefully lay the foundation for larger definitive studies.

Early changes in physiological variables after stroke

Several aspects of physiology, notably blood pressure, body temperature, blood glucose, and blood oxygen saturation, may be altered after an ischemic stroke and intracerebral hemorrhage. Generally, blood pressure and temperature rise acutely after a stroke, before returning to normal. Blood glucose and oxygen levels may be abnormal in individuals, but they do not follow a set pattern. Several aspects of these physiological alterations remain unclear, including their principal determinants - whether they genuinely affect prognosis (as opposed to merely representing underlying processes such as inflammation or a stress response), whether these effects are adaptive or maladaptive, whether the effects are specific to certain subgroups (e.g. lacunar stroke) and whether modifying physiology also modifies its prognostic effect. Hypertension and hyperglycemia may be helpful or harmful, depending on the perfusion status after an ischemic stroke; the therapeutic response to their lowering may be correspondingly variable. Hypothermia may provide benefits, in addition to preventing harm through protection from hyperthermia. Hypoxia is harmful, but normobaric hyperoxia is unhelpful or even harmful in normoxic patients. Hyperbaric hyperoxia, however, may be beneficial, though this remains unproven. The above-mentioned uncertainties necessitate generally conservative measures for physiology management, although there are notably specific recommendations for thrombolysis-eligible patients. Stroke unit care is associated with better outcome, possibly through better management of poststroke physiology. Stroke units can also facilitate research to clarify the relationship between physiology and prognosis, and to subsequently clarify management guidelines.

Correlation between interleukin-6 promoter and C-reactive protein (CRP) polymorphisms and CRP levels with the Mainz Severity Score Index for Fabry disease

OBJECTIVES

Fabry disease is a multisystem disorder with phenotypic heterogeneity only partially explained by genotype. Elevated interleukin-6 (IL-6) plasma levels and C-reactive protein (CRP) serum levels are associated with increased risk and worse outcome of ischaemic events, a serious prognostic sign in Fabry disease.

METHODS

56 patients (34 hemizygous males, 22 females; 5 children) were studied. A promoter polymorphism -174G > C of the IL-6 gene associated with serum IL-6 levels was compared with the Mainz Severity Score Index (MSSI) in patients with Fabry disease. CRP levels and polymorphism 1059 G > C were evaluated as markers of inflammation to ascertain the possibility of an inflammatory mechanism of IL-6. Nonparametric ANOVA, Fisher's exact, Bonferroni, and Hardy-Weinberg (HW) statistics were used.

RESULTS

Mean age of adults = 42 (range 26-58) years; 29 patients received enzyme therapy (ERT). Mean total MSSI = 26.7 (range 14.2-39.2) points, i.e. moderate disease, but females were lower (total 23.4 +/- 12.6 vs 32.2 +/- 13.6). Controls but not patients were in HW equilibrium. Significant correlation existed between all sub-scores of the MSSI and IL-6 genotypes in females but only with three MSSI sub-scores for males. The IL-6 C/C genotype was significantly correlated with the neurological, general and total MSSI sub-scores, generally twofold higher. There were no statistically significant correlations with CRP levels/polymorphisms and MSSI sub-scores nor with IL-6 polymorphisms. CRP levels decreased after ERT in patients with IL-6 G/G or G/C genotypes but increased in patients with C/C (p = 0.003).

CONCLUSIONS

The prevalence of the IL-6 C allele significantly influences MSSI, i.e. clinical severity, especially in females. This is unrelated to IL-6 as a pro-inflammatory marker as demonstrated by lack of correlations with CRP levels and genotypes. IL-6 -174 polymorphic C allele may be a prognostic marker in Fabry disease, especially in females.