The relationship between serum mannose-binding lectin levels and acute ischemic stroke risk

Complement activation and inflammation have been suggested in the pathogenesis of stroke, mannose-binding lectin (MBL) were found to have roles during the process. The aim of this study was to investigate the relationship between acute ischemic stroke (AIS) and serum MBL levels in Chinese population. From January 1 to June 30 2013, all patients with first-ever AIS were recruited to participate in the study. Serum MBL levels and routine test were examined. The National Institutes of Health Stroke Scale (NIHSS) score was assessed on admission blinded to MBL levels. During the inclusion period, 148 patients with AIS were registered and completed study. The results indicated that the serum MBL levels were significantly (p < 0.0001) higher in acutely ischemic stroke patients as compared to normal controls [1,332; interquartile range (IQR) 996-2,134 μg/L and 897; IQR 678-1,100 μg/L, respectively]. There was a correlation between serum levels of MBL and NIHSS score [r (spearman) = 0.608, p < 0.0001). In multivariate analysis, serum MBL as a continuous variable was associated with an increased risk of AIS, after adjustment for above possible confounders (OR 1.002, 95 % CI 1.001-1.008; p < 0.0001). These results indicated that elevated MBL levels could be considered as an independent stroke risk factor in Chinese population, suggesting a role of MBL and the lectin pathway of complement activation in the pathogenesis of stroke.

Plasma copeptin and long-term outcomes in acute ischemic stroke

OBJECTIVE

The identification of patients at highest risk for adverse outcome who are presenting with acute ischemic stroke to the emergency department remains a challenge. This study firstly investigates the long-term prognostic value of the stress marker copeptin in Chinese patients with acute ischemic stroke.

METHODS

In a prospective study, copeptin levels were measured using a new sandwich immunoassay on admission in plasma of 245 consecutive patients with an acute ischemic stroke. The prognostic value of copeptin to predict the functional outcome and mortality within one year was compared with the National Institutes of Health Stroke Scale score and with other known outcome predictors.

RESULTS

Patients with an unfavorable outcomes and non-survivors had significantly increased copeptin levels on admission (P < 0.0001 and P < 0.0001). Multivariate Cox regression analysis adjusted for common risk factors showed that copeptin was an independent predictor of functional outcome (hazard ratio = 3.88; 95% CI: 1.94-7.77) and non-survivors (hazard ratio = 5.99; 95% CI: 2.55-14.07). The area under the receiver operating characteristic curve of copeptin was 0.75 (95% CI, 0.70-0.82) for functional outcome and 0.867 (95% CI, 0.802-0.933) for mortality.

CONCLUSIONS

Copeptin levels are a novel and complementary biomarker to predict functional outcome and mortality 1 year after acute ischemic stroke.

Plasma copeptin levels are inversely associated with intima-media-thickness in men: the population-based KORA F4 study

Background

Elevated plasma preprovasopressin (copeptin) levels are associated with cardiovascular complications as well as with an increased risk for type 2 diabetes (T2D). Here, we studied, whether plasma copeptin is related to carotid intima-media thickness (IMT), a measure of early atherosclerosis, and may thus be one explanation for the high cardiovascular risk in T2D.

Methods

Plasma concentrations of copeptin and IMT of the common carotid artery were determined in 1275 participants of the population-based KORA F4 study. We used linear regression models to investigate associations between copeptin levels and IMT.

Results

In the whole study group, copeptin levels were not significantly associated with IMT after adjustment for age and sex. Copeptin and IMT were significantly inversely associated after multivariable adjustment in the total cohort (β = -0.020 mm, 95% CI: -0.037 mm; -0.003 mm), in men (β = -0.035 mm, 95% CI: -0.061 mm; -0.009 mm) and in study participants with prediabetes (β = -0.041 mm, 95% CI: -0.078 mm; -0.005 mm) comparing quartile 4 vs quartile 1. The negative association of copeptin and IMT in men was present after adjustment for age alone. In women and patients with T2D, copeptin was not significantly associated with IMT.

Conclusions

Plasma copeptin was not associated with an increased IMT in our study cohort. In contrast, copeptin levels were related to a lower IMT in men and subjects with prediabetes, suggesting that elevated copeptin concentrations do not exert proatherogenic effects on carotid arteries.

Prognostic value of plasma neuroendocrine biomarkers in patients with acute ischaemic stroke

Inflammation and activation of the neuroendocrine systems comprise important aspects of stroke pathophysiology. The present study investigated whether baseline plasma brain natriuretic peptide (BNP), N-terminal pro-brain natriuretic peptide (NT-proBNP), cortisol and copeptin levels on admission can predict short-term outcomes and mortality after acute ischaemic stroke. The study group consisted of 189 patients who had their first acute ischaemic stroke. Plasma levels of BNP, NT-proBNP, cortisol and copeptin were evaluated to determine their value with respect to predicting functional outcome and mortality within 3 months. As a result of cardiovascular and neurological investigations (including imaging techniques), lesion size, stroke subtype classification and clinical outcome after 3 months were determined. Plasma levels of BNP, NT-proBNP, cortisol and copeptin were associated with stroke severity, as well as short-term functional outcomes. After adjusting for all other significant outcome predictors, NT-proBNP, cortisol and copeptin remained as independent outcome predictors. In the receiver operating characteristic curve analysis, the biomarker panel (including BNP, NT-proBNP, cortisol and copeptin) predicted functional outcome and death within 90 days significantly more efficiently than the National Institute of Health Stroke Scale (NIHSS) or the biomarker alone. Copeptin showed a significantly greater discriminatory ability as a single biomarker compared to BNP, NT-proBNP, cortisol and NIHSS score. These results suggest that a biomarker panel may add valuable and time-sensitive prognostic information in the early evaluation of acute ischaemic stroke. This may provide a channel for interventional therapy in acute stroke.

Concentrations of the stress hormone copeptin increase upon hypoglycaemia in patients with type 1 diabetes dependent of hypoglycaemia awareness

Objective

Copeptin, a marker for stress mirroring vasopressin concentrations, has been shown to increase upon insulin-induced hypoglycaemia in patients after transsphenoidal surgery of pituitary adenomas. Patients with type 1 diabetes mellitus are prone to hypoglycaemia, but no data about copeptin levels upon hypoglycaemia are available. Furthermore, the perception of hypoglycaemia can vary from total unawareness to disabling episodes. The aim of this study was to investigate whether copeptin increases upon hypoglycaemia in patients with type 1 diabetes mellitus and is associated with the degree of hypoglycaemia awareness.

Materials and Methods

In this prospective observational study, 17 patients with type 1 diabetes underwent a standardized insulin infusion test. Blood sampling for glucose and copeptin was performed at baseline and after 60 minutes (min). To assess hypoglycaemia associated symptoms the Mood and Symptom Questionnaire (MSQ) was conducted at baseline and after 60 min.

Results

During insulin infusion, blood glucose decreased from 5.1 (SD±0.2) to 3.0 (±0.5) mmol/L at 60 min (p<0.001). Copeptin concentrations increased from 3.2 (±1.7) to 3.8 (±1.9) pmol/L (p = 0.03). Mood and Symptoms Questionnaire scores increased from 14 (±3.0) to 18 (±5.8), (p = 0.006). Patients with good hypoglycaemia awareness had an increase in copeptin from 3.0 (±1.8) to 4.2 (±2.4) pmol/L (p = 0.03) in contrast to patients more unaware of hypoglycaemia who only showed an increase in copeptin from 3.3 (±1.6) to 3.6 (±1.4) pmol/L (p = 0.4). There was a trend to a larger copeptin increase in patients aware of hypoglycemia compared to patients unaware of hypoglycemia (p = 0.074).

Conclusion

Copeptin increases in patients with type 1 diabetes upon insulin induced hypoglycaemia. Interestingly, the copeptin increase seems associated with the degree of hypoglycaemia awareness. This hypothesis warrants further verification.

Trial Registration

ClinicalTrials.gov NCT00515801

Plasma midregional pro-adrenomedullin improves prediction of functional outcome in ischemic stroke

Background

To evaluate if plasma levels of midregional pro-adrenomedullin (MR-proADM) improve prediction of functional outcome in ischemic stroke.

Methods

In 168 consecutive ischemic stroke patients, plasma levels of MR-proADM were measured within 24 hours from symptom onset. Functional outcome was assessed by the modified Rankin Scale (mRS) at 90 days following stroke. Logistic regression, receiver operating characteristics (ROC) curve analysis, net reclassification improvement (NRI), and Kaplan-Meier survival analysis were applied.

Results

Plasma MR-proADM levels were found significantly higher in patients with unfavourable (mRS 3–6) compared to favourable (mRS 0–2) outcomes. MR-proADM levels were entered into a predictive model including the patients' age, National Institutes of Health Stroke Scale (NIHSS), and the use of recanalization therapy. The area under the ROC curve did not increase significantly. However, category-free NRI of 0.577 (p<0.001) indicated a significant improvement in reclassification of patients. Furthermore, MR-proADM levels significantly improved reclassification of patients in the prediction of outcome by the Stroke Prognostication using Age and NIHSS-100 (SPAN-100; NRI = 0.175; p = 0.04). Kaplan-Meier survival analysis showed a rising risk of death with increasing MR-proADM quintiles.

Conclusions

Plasma MR-proADM levels improve prediction of functional outcome in ischemic stroke when added to the patients' age, NIHSS on admission, and the use of recanalization therapy. Levels of MR-proADM in peripheral blood improve reclassification of patients when the SPAN-100 is used to predict the patients' functional outcome.

Relationship between plasma copeptin levels and complications of community-acquired pneumonia in preschool children

High plasma copeptin level has been associated with clinical outcomes after acute illness. The present study was undertaken to investigate the plasma copeptin concentrations in preschool children with community-acquired pneumonia (CAP) and to analyze the correlations of copeptin with CAP-related complications and pleural effusion. Plasma copeptin concentrations of 100 healthy children and 165 preschool children with CAP were measured. 35 children (21.2%) presented with complicated CAP and 28 children (17.0%) presented with pleural effusion. The admission copeptin levels were significantly increased in all patients (49.7 ± 21.4 pmol/L), children with complicated CAP (73.0 ± 16.9 pmol/L), those with uncomplicated CAP (43.4 ± 17.8 pmol/L), those with pleural effusion (70.9 ± 17.4 pmol/L) and those without pleural effusion (45.3 ± 19.5 pmol/L) compared with healthy control individuals (9.0 ± 2.7 pmol/L, all P<0.001). Multivariate logistic regression analysis showed that plasma copeptin levels were independently related to CAP-related complications (odds ratio 1.214, 95% confidence interval 1.104-1.872, P<0.001) and pleural effusion (odds ratio 1.226, 95% confidence interval 1.109-1.917, P<0.001). A receiver operating characteristic curve analysis showed plasma copeptin level better predicted CAP-related complications (area under curve 0.876, 95% confidence interval 0.815-0.922) and pleural effusion (area under curve 0.831, 95% confidence interval 0.765-0.885). Thus, plasma copeptin level may represent a novel biomarker for predicting CAP-related complications in preschool children.

Copeptin: a new marker in cardiology

Copeptin, the C-terminal part of the prohormone of vasopressin (AVP), is released together with AVP in stoichiometric concentrations reflecting an individual's stress level. Copeptin has come to be regarded as an important marker for identifying high-risk patients and predicting outcomes in a variety of diseases. It improves the clinical value of commonly used biomarkers and the tools of risk stratification. Elevated AVP activation and higher copeptin concentrations have been previously described in acute systemic disorders. However, the field that could benefit the most from the introduction of copeptin measurements into practice is that of cardiovascular disease. Determination of copeptin level emerges as a fast and reliable method for differential diagnosis, especially in acute coronary syndromes. A particular role in the diagnosis of acute myocardial infarction (AMI) is attributed to the combination of copeptin and troponin. According to available sources, such a combination allows AMI to be ruled out with very high sensitivity and negative predictive value. Moreover, elevated copeptin levels correlate with a worse prognosis and a higher risk of adverse events after AMI, especially in patients who develop heart failure. Some authors suggest that copeptin might be valuable in defining the moment of the introduction of treatment and its monitoring in high-risk patients. The introduction of copeptin into clinical practice might also provide a benefit on a larger scale by suggesting changes in the allocation of financial resources within the health system. Although very promising, further larger trials are required in order to assess the clinical benefits of copeptin in everyday practice and patient care.

Prognostic value of dehydroepiandrosterone-sulfate and other parameters of adrenal function in acute ischemic stroke

Background and Purpose

Acute stroke has a high morbidity and mortality. We evaluated the predictive value of adrenal function testing in acute ischemic stroke.

Methods

In a cohort of 231 acute ischemic stroke patients, we measured dehydroepiandrosterone (DHEA), DHEA-Sulfate (DHEAS), cortisol at baseline and 30 minutes after stimulation with 1 ug ACTH. Delta cortisol, the amount of rise in the 1 ug ACTH-test, was calculated. Primary endpoint was poor functional outcome defined as modified Rankin scale 3–6 after 1 year. Secondary endpoint was nonsurvival after 1 year.

Results

Logistic regression analysis showed that DHEAS (OR 1.21, 95% CI 1.01–1.49), but not DHEA (OR 1.01, 95% CI 0.99–1.04), was predictive for adverse functional outcome. Neither DHEA (OR 0.99, 95% CI 0.96–1.03) nor DHEAS (OR 1.10, 95% CI 0.82–1.44) were associated with mortality. Baseline and stimulated cortisol were predictive for mortality (OR 1.41, 95% CI 1.20–1.71; 1.35, 95% CI 1.15–1.60), but only basal cortisol for functional outcome (OR 1.20, 95% CI 1.04–1.38). Delta cortisol was not predictive for functional outcome (OR 0.86, 95% CI 0.71–1.05) or mortality (OR 0.92, 95% CI 0.72–1.17). The ratios cortisol/DHEA and cortisol/DHEAS discriminated between favorable outcome and nonsurvival (both p<0.0001) and between unfavorable outcome and nonsurvival (p = 0.0071 and 0.0029), but are not independent predictors for functional outcome or mortality in multivariate analysis (adjusted OR for functional outcome for both 1.0 (95% CI 0.99–1.0), adjusted OR for mortality for both 1.0 (95% CI 0.99–1.0 and 1.0–1.01, respectively)).

Conclusion

DHEAS and the cortisol/DHEAS ratio predicts functional outcome 1 year after stroke whereas cortisol levels predict functional outcome and mortality.

Trial Registration

ClinicalTrials.gov NCT00390962 (Retrospective analysis of this cohort).

High-sensitivity troponin assay improves prediction of cardiovascular risk in patients with cerebral ischaemia

BACKGROUND AND PURPOSE

Clinical scores are recommended for predicting cardiovascular risk in patients with cerebral ischaemia to inform secondary prevention. Blood biomarkers may improve prediction beyond clinical scores.

METHODS

Within the observational Find-AF trial (ISRCTN46104198), 197 patients >18 years of age with cerebral ischaemia and without atrial fibrillation had blood sampled at baseline. The predictive value of five biomarkers for a combined vascular endpoint (acute coronary syndrome, stroke, cardiovascular death) and all-cause mortality was determined, alone and in addition to the Essen Stroke Risk Score (ESRS), Stroke Prognostic Instrument 2 (SPI-2) and National Institutes of Health Stroke Scale (NIH-SS).

RESULTS

There were 23 vascular events (11.7%) and 13 deaths (6.6%) to 1 year follow-up. In multivariate analyses of all markers, only high-sensitivity troponin T (hsTropT) remained independently predictive for vascular events (p=0.045) and all-cause mortality (p=0.004). hsTropT was higher in patients with a vascular event (median 12.7 ng/ml vs 5.1 ng/ml), and patients with hsTropT above the median of 6.15 ng/ml had vascular events more frequently (HR 3.86, p=0.008). For prediction of vascular events as well as all-cause mortality, hsTropT significantly improved multivariate Cox regression models with ESRS, SPI-2 or NIH-SS. The c-statistic increased non-significantly from 0.695 (ESRS) or 0.710 (hsTropT) to 0.747 (ESRS+hsTropT) and from 0.699 (SPI-2) to 0.763 (SPI-2+hsTropT). No patient with a low-risk ESRS and an hsTropT below the median had a vascular event or died.

CONCLUSIONS

hsTropT predicts vascular events and all-cause mortality in patients with acute cerebral ischaemia and improves prediction beyond established clinical scores.

Plasma copeptin concentration and outcome after pediatric traumatic brain injury

Higher plasma copeptin level has been associated with poor outcomes of critical illness. The present study was undertaken to investigate the plasma copeptin concentrations in children with traumatic brain injury (TBI) and to analyze the correlation of copeptin with disease outcome. Plasma copeptin concentrations of 126 healthy children and 126 children with acute severe TBI were measured by enzyme-linked immunosorbent assay. Twenty-one patients (16.7%) died and 38 patients (30.2%) had an unfavorable outcome (Glasgow Outcome Scale score of 1-3) at 6 months. Plasma copeptin level was obviously higher in patients than in healthy children (46.2±20.8 pmol/L vs. 9.6±3.0 pmol/L, P<0.001). Plasma copeptin level was identified as an independent predictor for 6-month mortality [odds ratio (OR) 1.261, 95% confidence interval (CI) 1.112-1.538, P=0.005] and unfavorable outcome (OR 1.313, 95% CI 1.146-1.659, P=0.003). The predictive value of copeptin was similar to that of Glasgow Coma Scale (GCS) score for 6-month mortality [area under curve (AUC) 0.832, 95% CI 0.755-0.892 vs. AUC 0.873, 95% CI 0.802-0.926, P=0.412] and unfavorable outcome (AUC 0.863, 95% CI 0.790-0.918 vs. AUC 0.885, 95% CI 0.816-0.935, P=0.596). Copeptin improved the AUC of GCS score for 6-month unfavorable outcome (AUC 0.929, 95% CI 0.869-0.967, P=0.013), but not for 6-month mortality (AUC 0.887, 95% CI 0.818-0.936, P=0.600). Thus, plasma copeptin level represents a novel biomarker for predicting 6-month clinical outcome in children with TBI.

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.

Low serum copeptin levels in patients with obstructive sleep apnea

PURPOSE

Copeptin, the C-terminal fragment of antidiuretic hormone (ADH), is a new biomarker that has been found to be elevated in several cardiovascular disorders and is related with prognosis. Patients with obstructive sleep apnea demonstrate a tendency to develop coronary and cerebral atherosclerotic disease. Our aim was to investigate copeptin levels in untreated new diagnosed obstructive sleep apnea patients without manifest cardiovascular disorders in order to determine whether copeptin could be used as a biomarker in this group.

METHODS

A total of 60 patients with obstructive sleep apnea, diagnosed with polysomnography, and 23 healthy volunteers were enrolled into this study. Blood samples were collected after overnight fasting, and copeptin level was measured with an enzyme immunoassay method.

RESULTS

Patients with obstructive sleep apnea had a higher incidence of hypertension and body mass index but lower serum copeptin level (0.48 ± 0.24. vs. 0.64 ± 0.28 ng/ml, p = 0.007) compared with the healthy controls. There was no significant difference regarding to serum copeptin levels between the moderate (n = 13) and severe (n = 47) obstructive sleep apnea patients (0.42 ± 0.18 vs. 0.49 ± 0.26 ng/ml, p = 0.409).

CONCLUSIONS

Rather than reflecting a reduced risk for cardiovascular disorders, we consider that reduced copeptin level is related with disturbed ADH secretion in obstructive sleep apnea patients. Therefore, it would not be advisable to measure copeptin levels in obstructive sleep apnea patients to determine cardiovascular risk, while this marker could be valuable to demonstrate impairment in ADH regulation in this patient group.

Copeptin Level After Carotid Endarterectomy and Perioperative Stroke

We evaluated the prognostic value of copeptin levels in a cohort of surgical patients after elective carotid endarterectomy (CEA). Twenty-one patients with perioperative stroke were prospectively recruited. The diagnosis of cerebrovascular event (CVE) was confirmed by computed tomography. Additionally, 21 patients with CEA without any complications (control patients) were enrolled. Blood samples were taken within 3 hours of the symptom onset. Circulating copeptin level was significantly higher in patients with CVE when compared to controls ( P = .025), and significantly higher in nonsurvivors than in survivors ( P = .030) after CVE. Plasma concentrations of interleukin 6 (IL-6) and C-reactive protein (CRP) were also elevated in patients with CVE (IL-6: P = .043; CRP: P = .002). We conclude that the activation of the stress axis in patients with CEA results with copeptin elevation, but more so in patients with perioperative stroke. Copeptin may be a helpful biomarker for stroke risk assessment in patients after CEA.

Copeptin as a marker for severity and prognosis of aneurysmal subarachnoid hemorrhage

BACKGROUND

Grading of patients with aneurysmal subarachnoid hemorrhage (aSAH) is often confounded by seizure, hydrocephalus or sedation and the prediction of prognosis remains difficult. Recently, copeptin has been identified as a serum marker for outcomes in acute ischemic stroke and intracerebral hemorrhage (ICH). We investigated whether copeptin might serve as a marker for severity and prognosis in aSAH.

METHODS

Eighteen consecutive patients with aSAH had plasma copeptin levels measured with a validated chemiluminescence sandwich immunoassay. The primary endpoint was the association of copeptin levels at admission with the World Federation of Neurological Surgeons (WFNS) grade score after resuscitation. Levels of copeptin were compared across clinical and radiological scores as well as between patients with ICH, intraventricular hemorrhage, hydrocephalus, vasospasm and ischemia.

RESULTS

Copeptin levels were significantly associated with the severity of aSAH measured by WFNS grade (P = 0.006), the amount of subarachnoid blood (P = 0.03) and the occurrence of ICH (P = 0.02). There was also a trend between copeptin levels and functional clinical outcome at 6-months (P = 0.054). No other clinical outcomes showed any statistically significant association.

CONCLUSIONS

Copeptin may indicate clinical severity of the initial bleeding and may therefore help in guiding treatment decisions in the setting of aSAH. These initial results show that copeptin might also have prognostic value for clinical outcome in aSAH.

Copeptin and cardiovascular disease: a review of a novel neurohormone

Neurohormones (NHs) in the cascade of the arginine vasopressin (AVP) system have drawn particular attention in the recent years. Copeptin, the C-terminal portion of provasopressin, is a novel NH of the AVP system, and is known to be co-released with AVP from hypothalamus (neurohypophysis). As a surrogate marker of the AVP system, copeptin has gradually replaced AVP in several clinical studies largely due to its structural and methodological advantages. Copeptin has been regarded as a marker of non-specific stress response, and has also been suggested to have clinical implications in a variety of non-cardiovascular (pneumonia, sepsis, etc.) and cardiovascular conditions (heart failure and acute coronary syndromes (ACSs, etc.)). However, current data on relation of copeptin with other cardiovascular conditions ( arrhythmias, etc.) are still insufficient. The present review primarily focuses on general features of copeptin, its general clinical implications, and specifically aims to cover its potential clinical value in a variety of cardiovascular conditions.

The role of vasopressin V1A receptors in cytotoxic brain edema formation following brain injury

BACKGROUND

The hormone and neuropeptide arginine-vasopressin is designated to the maintenance of osmotic homoeostasis and blood pressure regulation. While experimental data show vasopressin V(1A) receptors to regulate aquaporin (AQP)4 water channel dependent brain water movement, the specific role in vasogenic and cytotoxic edema formation remains unclear. The present study was designed to quantify the V(1A) receptor mediated regional brain edema formation in two clinically relevant experimental models, brain injury combined with secondary insult and focal ischemia.

METHODS

Male Sprague-Dawley rats were randomly assigned to a continuous infusion of vehicle (1 % DMSO) or the selective non-peptide V(1A) antagonist SR49059 (83nM = 1 mg/kg) starting before controlled cortical impact (CCI) injury plus hypoxia and hypotension (HH, 30 min), or middle cerebral artery (MCA) occlusion (2 h + 2 h reperfusion).

RESULTS

A global analysis of brain water content by the wet/dry weight method allowed optimizing the SR49059 dosage, and demonstrated the down-regulation of brain AQP4 expression by immunoblotting. Microgravimetrical quantification in 64 one mm(3) samples per animal (n = 6 per group) from bregma +2.7 to -6.3 mm analysis demonstrated brain edema to be reduced at 4 h by SR49059 treatment in the injured and contralateral cortex following CCI + HH (p = 0.007, p < 0.001) and in the infarct area following MCA occlusion (p = 0.013, p = 0.002, p = 0.004).

CONCLUSIONS

Our findings demonstrate that an early cytotoxic brain edema component following brain injury plus secondary insult or focal ischemia results from a vasopressin V(1A) receptor mediated response, and occurs most likely through AQP4 up-regulation. The V(1A) antagonist SR49059 offers a new avenue in brain edema treatment and prompts further study into the role of vasopressin following brain injury.

Year in review 2011: Critical Care--Neurocritical care

Contributions from the neurosciences to Critical Care in 2011 covered an array of topics. We learned about potential biomarkers for, and the effect of cerebral oxygen metabolism on, delirium, in addition to treatment of the latter. A group of investigators studied surface cooling in healthy awake volunteers, and incidence of infection associated with therapeutic hypothermia. The effects of statin and erythropoietin on stroke were revisited, and the role of adhesion molecule in the inflammatory reaction accompanying intracerebral hemorrhage was scrutinized. Biomarkers in subarachnoid hemorrhage and their relationship to vasospasm and outcome, and effect of daylight on outcome in this patient population, as well as a new meta-analysis of statin therapy were among the research in subarachnoid hemorrhage. Moreover, 2011 witnessed the publication of a multidisciplinary consensus conference's recommendations on the critical care management of subarachnoid hemorrhage. Results of studies regarding the diagnosis and vascular complications of meningitis were reported. Traumatic brain injury received its share of articles addressing therapy with hypertonic saline and surgical decompression, the development of coagulopathy, and biomarkers to help with prognostication. Finally, research on the treatment of Guillain-Barre syndrome in children, prediction of long-term need of ventilatory support, and pathophysiology of critical illness polyneuropathy and myopathy were reported.

The prognostic value of copeptin for acute intracerebral hemorrhage patients

The aim of the current study was to examine the prognostic value of copeptin for acute intracerebral hemorrhage (ICH) patients. A total of 120 patients were recruited. The plasma copeptin levels were measured using sandwich immunoassays. The hematoma volume, Glasgow coma scale (GCS) and ICH score were evaluated. The 90-day functional outcomes were measured with the modified Rankin scale (mRS). Copeptin correlated positively with hematoma volume (r=0.61, P=0.000), Hemphill scores (r=0.78, P=0.000) and white blood cell counts (r=0.58, P=0.000), whereas copeptin correlated negatively with GCS scores (r=-0.79, P=0.000). Copeptin levels were also higher in patients with an unfavorable functional outcome at 90 days than in patients with a favorable outcome (4.14±0.87 vs. 3.09±0.30 ng/ml; t=8.001, P=0.00). Monovariate logistic regression analysis results suggest that copeptin is a predictor of the 90-day functional outcomes of ICH patients (OR=3.17, 95% CI 2.01-4.35, P=0.003. Multivariate logistic regression analysis results indicate that copeptin is an independent predictor of the 90-day functional outcomes of ICH patients.

Determinants of plasma copeptin: a systematic investigation in a pediatric mechanical ventilation model

Copeptin, the C-terminal part of the arginine vasopressin precursor peptide, holds promise as a diagnostic and prognostic plasma biomarker in various acute clinical conditions. Factors influencing copeptin response in the critical care setting are only partially established and have not been investigated systematically. Using an in vivo infant ventilation model (Wistar rats, 14 days old), we studied the influence of commonly occurring stressors in critically ill children. In unstressed ventilated rats basal median copeptin concentration was 22pmol/L. In response to respiratory alkalosis copeptin increased 5-fold, while exposure to hypoxemia, high PEEP, hemorrhage, and psycho-emotional stress produced a more than 10-fold increase. Additionally, we did not find a direct association between copeptin and acidosis, hypercapnia, and hyperthermia. Clinicians working in the acute critical care setting should be aware of factors influencing copeptin plasma concentrations. Moreover, our results do have implications for animal studies in the field of stress research.

Copeptin, procalcitonin and routine inflammatory markers-predictors of infection after stroke

Background

Early predictors for the development of stroke-associated infection may identify patients at high risk and reduce post-stroke infection and mortality.

Methods

In 383 prospectively enrolled acute stroke patients we assessed time point and type of post-stroke infections (i.e. pneumonia, urinary tract infection (UTI) other infection (OI)). Blood samples were collected on admission, and days 1, and 3 to assess white blood cells (WBC), monocytes, C-reactive protein (CRP), procalcitonin (PCT), and copeptin. To determine the magnitude of association with the development of infections, odds ratios (OR) were calculated for each prognostic blood marker. The discriminatory ability of different predictors was assessed, by calculating area under the receiver operating characteristic curves (AUC). Prognostic models including the three parameters with the best performance were identified.

Results

Of 383 patients, 66 (17.2%) developed an infection after onset of stroke. WBC, CRP, copeptin and PCT were all independent predictors of any infection, pneumonia and UTI developed at least 24 hours after measurements. The combination of the biomarkers WBC, CRP and copeptin (AUC: 0.92) and WBC, CRP and PCT (AUC: 0.90) showed a better predictive accuracy concerning the development of pneumonia during hospitalization compared to each marker by itself (p-Wald <0.0001).

Conclusion

Among ischemic stroke patients, copeptin, PCT, WBC and CRP measured on admission were predictors of infection in general, and specifically for pneumonia and UTI within 5 days after stroke. The combination of these biomarkers improved the prediction of patients who developed an infection.

Blood levels of copeptin on admission predict outcomes in out-of-hospital cardiac arrest survivors treated with therapeutic hypothermia

Introduction

Prognostic stratification of cardiac arrest survivors is essential for the selection of the most appropriate therapeutic strategy. However, accurate early outcome predictions for this patient population remain challenging. At present, there is a lack of data examining the prognostic value of C-terminal provasopressin (copeptin) in cardiac arrest survivors.

Methods

A group of 40 out-of-hospital cardiac arrest survivors who were treated with endovascular hypothermia was analyzed. Copeptin levels were measured in blood samples taken at admission using a commercially available immunoassay. Neurological outcome was assessed at 30 days post admission according to the Cerebral Performance Category (CPC): CPC 1, no neurological deficit; CPC 2, mild to moderate dysfunction; CPC 3, severe dysfunction; CPC 4, coma; and CPC 5, death.

Results

Copeptin levels were significantly lower in patients with CPC 1 compared with CPC 2 or CPC 3 to CPC 5 (74.3 ± 14.4 pmol/l, 219.8 ± 33.9 pmol/l and 302.7 ± 52.1 pmol/l, respectively; P < 0.0001). Using an optimal cutoff value ≤ 217.9 pmol/l calculated from the receiver operating characteristic curve (area under curve = 0.801, 95% confidence interval = 0.644 to 0.910; P = 0.0001), the sensitivity of predicting survival with good neurological outcome was 78.6% and the specificity was 75.0%. Multiple logistic regression analysis revealed that a copeptin level > 217.9 pmol/l was an independent predictor of severe neurological dysfunction or death, with an adjusted odds ratio of 27.00 (95% confidence interval = 2.27 to 321.68; P = 0.009).

Conclusion

The present study found that copeptin levels have a significant prognostic value at the time of hospital admission, and are a promising diagnostic tool for predicting outcomes in out-of-hospital cardiac arrest survivors.

Epidemiology and risk factors

PURPOSE OF REVIEW

: This article presents current knowledge on stroke epidemiology. It covers recent data on the global burden of stroke, disparities, silent stroke, traditional and novel risk factors, and stroke triggers as well as the clinical implications of these findings.

RECENT FINDINGS

: Stroke is the third leading cause of death and the leading cause of chronic disability in the United States, and the burden of stroke worldwide is even greater. Large international and US case-control and prospective cohort studies have demonstrated disparities in stroke mortality and incidence. They have also shed light on the relative importance of several well-established, modifiable risk factors for ischemic stroke, such as hypertension, atrial fibrillation, other cardiac diseases, hyperlipidemia, diabetes, cigarette smoking, physical inactivity, alcohol consumption, abdominal obesity, diet, and TIA. Research on other putative stroke risk factors (including inflammation, infection, renal disease, depression, stress, and others) is ongoing. Identifying stroke triggers may be another way to minimize stroke incidence if high-risk time windows can be determined.

SUMMARY

: Stroke is a major global health burden. While many of the risk factors for stroke are well known and have been studied for decades, recent studies continue to shed light on the distribution and severity of these problems.

Brain natriuretic peptide is associated with worsening and mortality in acute stroke patients but adds no prognostic value to clinical predictors of outcome

BACKGROUND

At the present time, the determination of the outcome of stroke patients is based on the analysis of clinical and neuroimaging data. The use of prognostic blood biomarkers could aid in decision-making processes, e.g. admitting patients to specialized stroke units. Although the prognostic role of natriuretic peptides has been studied in heart failure and coronary diseases, the value of brain natriuretic peptide (BNP) is less known within the field of strokes.

OBJECTIVE

We aimed to study the relationship between plasma levels of BNP and acute neurological worsening or mortality after stroke in a large cohort of patients (investigating both ischemic and hemorrhagic disease).

METHODS

Consecutive stroke patients (ischemic and hemorrhagic) admitted to the Stroke Unit of our University Hospital within 24 h of the onset of symptoms were included. Stroke severity was assessed according to the National Institutes of Health Stroke Scale (NIHSS) at admission and at discharge. Neurological worsening was defined as an increase of 4 or more points in the NIHSS score or death during the patient's stay at the Stroke Unit. Blood samples were drawn upon admission to measure plasma levels of BNP (Biosite Inc., San Diego, Calif., USA). Statistical analysis was performed using SPSS 15.0 and R software.

RESULTS

Altogether, 896 patients were included in the study. BNP plasma levels were higher among patients who deteriorated the most over time (n = 112; 90.5 vs. 61.2 ng/l; p = 0.006) or died (n = 83; 118.2 vs. 60.9 ng/l; p < 0.001). Multivariate logistic regression analysis indicated that plasma BNP level was an independent predictor of neurological worsening [BNP >56.7 ng/l; odds ratio (OR) = 1.64; p = 0.04] and death after stroke (BNP >65.3 ng/l; OR = 1.97; p = 0.034). Adding BNP level to other well-known clinical predictors of bad outcome did not significantly increase the predictive value.

CONCLUSIONS

Plasma levels of BNP measured during the acute phase of stroke are associated both with early neurological worsening and mortality. However, this biological information does not supply prognostic information which would add to clinical variables, which limits its use as a biomarker. Further investigation and systematic reviews are needed to clarify the role of natriuretic peptides in stroke outcome.

Time-dependent Cox regression: serial measurement of the cardiovascular biomarker proadrenomedullin improves survival prediction in patients with lower respiratory tract infection

BACKGROUND

The aim of this study was to determine the prognostic utility of serial measurement of the cardiovascular biomarker midregion proadrenomedullin (MR-proADM) in patients admitted with lower respiratory tract infection. In a previous trial in dyspneic patients (BACH trial) we could show that serial measurement of MR-proADM proves useful for risk assessment and patient monitoring. Models designed to evaluate serial biomarker measurements usually fail to answer two fundamental questions necessary to judge their clinical relevance: whether serial measurements provide additional information on top of the first measurement, and, if yes, at which time point a re-evaluation may be clinically useful.

METHOD

We apply an adapted time-dependent Cox model to data from the ProHosp trial, a prospective trial, which was observational in regards to application of prognostic biomarkers, where blood draws for biomarker evaluation were collected at day of patient inclusion, days 3, 5 and 7. In this trial, the cardiovascular biomarker MR-proADM was evaluated for its ability to predict survival in comparison to clinical risk scores.

RESULTS

With the adapted time-dependent Cox model, we could demonstrate a significant added value of the follow up measurements on top of that obtained on admission. Despite a high correlation between serial measurements, the gain can be observed as early as 3 days after inclusion. We illustrate the added prognostic value and clinical relevance of re-evaluation via Kaplan-Meier plots.

CONCLUSION

We could demonstrate that the prognostic biomarker MR-proADM can potentially serve as a outcome monitoring marker in patients admitted with lower respiratory tract infections.

Serum biomarkers of spontaneous intracerebral hemorrhage induced secondary brain injury

Intracerebral hemorrhage (ICH) is a devastating form of stroke associated with a high rate of morbidity and mortality. It is now believed that much of this damage occurs in the subacute period following the initial insult via a cascade of complex pathophysiologic pathways that continues to be investigated. Increased levels of certain serum proteins have been identified as biomarkers that may reflect or directly participate in the inflammation, blood brain barrier disruption, endothelial dysfunction, and neuronal and glial toxicity that occur during this secondary period of cerebral injury. Some of these biomarkers have the potential to serve as therapeutic targets or surrogate endpoints for future research or clinical trials. Others may someday augment current clinical techniques in diagnosis, risk-stratification, prognostication, treatment decision and measurement of therapeutic efficacy. While much work remains to be done, biomarkers show significant potential to expand clinical options and improve clinical management, thereby reducing mortality and improving functional outcomes in ICH patients.

Evolving role of biomarkers in acute cerebrovascular disease

The development of a clinically validated biomarker of acute cerebral ischemia would have the potential to facilitate the use of time-sensitive reperfusion strategies, allow for individualization of patient care by predicting relative risk of hemorrhage and volume of penumbral tissue, and add valuable prognostic information for patients presenting with acute stroke. Additionally, a stroke biomarker might benefit early stage clinical research by serving as a surrogate measure of ischemic injury. Although at present there are no clinically validated biomarkers of acute stroke, previous studies have focused on markers associated with different components of the ischemic cascade, including microglial activation, inflammation, oxidative stress, neuronal injury, hemostasis, and endothelial dysfunction. Evolving technologies have provided high throughput approaches to investigate potential gene and protein signatures, and methods to measure newly discovered markers of cell death and immune responses. Prior to defining the clinical utility of stroke biomarkers, it is critical to understand the inherent limitations of a biomarker-based approach and define its potential value for providing adjunctive diagnostic and prognostic information. The identification and validation of a clinically relevant biomarker, or panel of markers, of stroke will ultimately require incorporation of both stringent research design and assessment in the clinical context in which the marker will be used.

Release patterns of copeptin and troponin in Tako-Tsubo cardiomyopathy

Copeptin, in addition to troponin, has recently been suggested for non-invasive differentiation between Tako-Tsubo cardiomyopathy (TTC) and acute myocardial infarction (AMI). In order to test this hypothesis, we investigated release patterns of pituitary copeptin and cardiac troponin in 49 patients with TTC and 49 age-, gender-, and ECG-matched control patients with AMI. Elevated copeptin levels (i.e. >12 pmol/l) at cardiac catheterization were found in 23/49 (47%) TTC patients and 25/49 (51%) AMI patients. Of these, median copeptin levels were almost identical in both cohorts (34.1 vs. 35.4 pmol/l). Subgroup analysis according to ECG changes revealed that AMI patients with ST-segment elevation had 3.6-fold higher copeptin levels than AMI patients without ST-segment elevation (p<0.05). Furthermore, in patients with TTC and atypical (midventricular) ballooning on left ventricular angiography, copeptin levels were 5.7-fold higher than in TTC patients with a typical (apical) type of ballooning (p<0.01). Elevated troponin T levels (i.e. >0.01 μg/l) at catheterization were detectable in 47/49 (96%) TTC patients and 45/49 (92%) AMI patients; however, peak levels did not differ significantly between both cohorts (median 0.35 vs. 0.27 μg/l). Subgroup analysis according to ECG changes revealed 2-fold higher peak troponin T levels in TTC patients presenting with ST-segment elevation than non-ST-segment elevation (p<0.05). In conclusion, copeptin does not seem to significantly increase non-invasive differentiation between TTC and AMI. At present, coronary angiography, specifically in patients with ST-segment elevation at presentation remains absolutely mandatory.

Copeptin is associated with one-year mortality and functional outcome in patients with acute spontaneous basal ganglia hemorrhage

High plasma copeptin levels have been found to be associated with short-term poor outcome after intracerebral hemorrhage (ICH). We furthermore evaluate the relation of plasma copeptin levels to long-term outcome and early neurological deterioration after ICH. Fifty healthy controls and 89 patients with acute spontaneous basal ganglia hemorrhage were recruited in this study. Plasma copeptin concentrations on admission measured by enzyme-linked immunosorbent assay were considerably high in patients than healthy controls. A multivariate analysis identified plasma copeptin level as an independent predictor for 1-year mortality, 1-year unfavorable outcome (modified Rankin Scale score>2) and early neurological deterioration. A receiver operating characteristic curve showed that the predictive value of plasma copeptin concentration was similar to that of National Institutes of Health Stroke Scale scores for long-term poor outcome and early neurological deterioration. However, copeptin did not obviously improve the predictive values of National Institutes of Health Stroke Scale scores. Thus, increased plasma copeptin level is an independent prognostic marker of 1-year mortality, 1-year unfavorable outcome and early neurological deterioration after ICH.

Copeptin as a prognostic factor for major adverse cardiovascular events in patients with coronary artery disease

BACKGROUND

C-terminal portion of provasopressin (copeptin) has recently been discussed as a novel biomarker for the early rule-out of acute myocardial infarction (AMI). The aim is to investigate the prognostic value of copeptin with regard to mortality and morbidity in patients with symptomatic coronary artery disease (CAD).

METHODS

We consecutively recruited a cath lab cohort of 2,700 patients (74.1% male; AMI, n=1316; stable angina pectoris, n=1384) presenting to the emergency department of a large primary care hospital. All patients received coronary angiography. Copeptin and other laboratory markers were sampled at the time of presentation or in the cath lab. Clinical outcomes were assessed by hospital chart analysis and telephone interviews. 2621 patients (97.1%) have been successfully followed-up at three months. The primary endpoint was a combined endpoint of rehospitalization for cardiovascular events, stroke, and all-cause death.

RESULTS

Using receiver operating characteristic curves, we calculated areas under the curve of 0.703 (95%confidence interval(CI):0.681-0.725) for the composite endpoint after three months (myocardial reinfarction, stroke, all-cause death;n=183), and 0.770 (95%CI:0.736-0.803) for all-cause death (n=76) for copeptin. A cutoff value of 21.6 pmol/L for the composite endpoint yielded a sensitivity of 56.3% and a specificity of 78.6%. The predictive performance of copeptin was independent of other clinical variables or cardiovascular risk factors, and superior to that of troponin I or other cardiac biomarkers (all:P<0.0001).

CONCLUSIONS

Copeptin may help in the prediction of major adverse cardiovascular events in patients with symptomatic CAD. Further studies should substantiate the findings and support the suggested cutoff value of the present study.

The role of copeptin as a diagnostic and prognostic biomarker for risk stratification in the emergency department

The hypothalamic-pituitary-adrenal axis is activated in response to stress. One of the activated hypothalamic hormones is arginine vasopressin, a hormone involved in hemodynamics and osmoregulation. Copeptin, the C-terminal part of the arginine vasopressin precursor peptide, is a sensitive and stable surrogate marker for arginine vasopressin release. Measurement of copeptin levels has been shown to be useful in a variety of clinical scenarios, particularly as a prognostic marker in patients with acute diseases such as lower respiratory tract infection, heart disease and stroke. The measurement of copeptin levels may provide crucial information for risk stratification in a variety of clinical situations. As such, the emergency department appears to be the ideal setting for its potential use. This review summarizes the recent progress towards determining the prognostic and diagnostic value of copeptin in the emergency department.

Growth-differentiation factor-15 and functional outcome after acute ischemic stroke

Blood biomarkers may improve the performance in predicting early stroke outcome beyond well-established clinical factors. We investigated the value of growth-differentiation factor-15 (GDF-15) to predict functional outcome after 90 days in a prospectively collected patient cohort with symptoms of acute ischemic stroke. Two hundred eighty-one patients with symptoms of acute ischemic stroke were prospectively investigated. Serial blood samples for GDF-15 analysis were obtained after the admission of the patient, after 6 and 24 h. Primary outcome was the dichotomized modified ranking scale (MRS) 90 days after the initial clinical event. Within the final study population (264 patients, mean age 70.3 ± 12.7 years, 55.3% male), National Institutes of Health Stroke Scale (NIH-SS) [odds ratio (OR) 1.269, 95% confidence interval (CI) 1.141–1.412, p < 0.001] and initial GDF-15 levels (OR 1.029, 95% CI 1.007–1.053, p = 0.011) were independently associated with a MRS ≥ 2 after day 90 after multiple regression analysis. Growth-differentiation factor-15 levels increase with higher NIH-SS-tertiles (p = 0.005). Receiver-operator characteristic curves demonstrated a discriminatory accuracy to predict unfavourable stroke outcome of 0.629 (95% CI 0.558–0.699), 0.753 (95% CI 0.693–812) and 0.774 (95% CI 0.717–0.832) for GDF-15, NIH-SS and the combination of these variables. The additional use of GDF-15 to NIH-SS ameliorates the model with a net reclassification index of 0.044 (p = 0.541) and integrated discrimination improvement of 0.034 (p = 0.443). Growth-differentiation factor-15 as an acute stroke biomarker independently predicts unfavourable functional 90 day stroke outcome. Discriminatory value in addition to NIH-SS is only modestly distinct.

Prognostic value of copeptin: one-year outcome in patients with traumatic brain injury

High plasma copeptin level has been associated with one-month mortality after traumatic brain injury. However, not much is known regarding its relation with long-term outcome. Thus, we investigated the ability of copeptin to predict 1-year outcome in patients with traumatic brain injury. One hundred and six healthy controls and 106 patients with acute severe traumatic brain injury were included. Plasma samples were obtained on admission. Its concentration was measured by enzyme-linked immunosorbent assay. Forty-eight patients (45.3%) suffered from unfavorable outcome (Glasgow Outcome Scale score of 1-3) and 31 patients (29.2%) died in 1 year after traumatic brain injury. Upon admission, plasma copeptin level in patients was substantially higher than that in healthy controls. A forward stepwise logistic regression selected plasma copeptin level as an independent predictor for 1-year unfavorable outcome and mortality of patients. A receiver operating characteristic curve analysis showed plasma copeptin level predicted 1-year unfavorable outcome and mortality obviously. The predictive value of the copeptin concentration was thus similar to that of Glasgow Coma Scale score for the prediction of unfavorable outcome and mortality after 1 year. In a combined logistic-regression model, copeptin improved the area under curve of Glasgow Coma Scale score for the prediction of unfavorable outcome and mortality after 1 year, but the differences were not significant. Thus, copeptin level is a useful, complementary tool to predict functional outcome and mortality 1 year after traumatic brain injury.

Copeptin is associated with mortality in patients with traumatic brain injury

BACKGROUND

High serum copeptin levels are associated with injury severity after traumatic brain injury (TBI). However, not much is known regarding its relation with mortality. Thus, we sought to evaluate its relation with disease mortality.

METHODS

Fifty healthy controls and 94 patients with acute severe TBI were included. Plasma samples were obtained on admission and at days 1, 2, 3, 5, and 7. Its concentration was measured by enzyme-linked immunosorbent assay.

RESULTS

Twenty-six patients (27.7%) died from TBI in a month. After brain injury, plasma copeptin level in patients increased during the 6-hour period immediately, peaked in 24 hours, plateaued at day 2, decreased gradually thereafter, and was substantially higher than that in healthy controls during the 7-day period. A forward stepwise logistic regression selected plasma copeptin level (odds ratio, 1.008; 95% confidence interval, 1.002-1.014; p = 0.010) as an independent predictor for 1-month mortality of patients. A multivariate linear regression showed that plasma copeptin level was negatively associated with Glasgow Coma Scale (GCS) score (t = -7.161; p < 0.001). A receiver operating characteristic curve identified plasma copeptin cutoff level (451.8 pg/mL) that predicted 1-month mortality with the optimal sensitivity (88.5%) and specificity (75.0%) values (area under curve, 0.874; 95% confidence interval, 0.789-0.933; p < 0.001). The area under curve of plasma copeptin level was similar to that of GCS score (p = 0.299). However, copeptin did not statistically significantly improve the area under curve of GCS score (p = 0.413).

CONCLUSIONS

Increased plasma copeptin levels are associated with mortality after TBI.

Pentraxin 3: a novel and independent prognostic marker in ischemic stroke

OBJECTIVE

Pentraxin 3 (PTX3) is one of the pattern-recognition receptors related to the initial step of the immune response with C-reactive protein, but the physiologic and pathologic functions are not fully understood. The purpose of the current study was to determine the impact of PTX3 levels on mortality after ischemic stroke.

METHODS

We consecutively enrolled 376 patients who had ischemic stroke between September 2004 and September 2006. The patients were divided into tertiles according to PTX3 levels. Cox regression analysis was used to determine hazard ratios (HRs) and 95% confidence intervals (CIs) of the PTX3 tertiles for all-cause mortality with adjustment for traditional risk factors and laboratory variables, including C-reactive protein.

RESULTS

During the follow-up, 19.4% of the patients were deceased. The median PTX3 levels were higher in the deceased patients (18.0 vs. 6.4 ng/mL, p<0.001). Based on Cox regression analysis, compared with the first tertile of PTX3, the adjusted HRs of the second and third tertiles for all-cause mortality were 1.24 (95% CI, 0.52-2.98) and 2.64 (95% CI, 1.19-5.85), respectively. When the log-transformed levels of PTX3 were incorporated as continuous variables, higher levels of PTX3 were also associated with an increased mortality (increase per log unit; HR, 1.60; 95% CI, 1.19-2.16).

CONCLUSIONS

We showed that higher levels of PTX3 are independently associated with increased mortality after ischemic stroke. Our results suggest that PTX3 may be used as a new powerful prognostic biomarker in patients with ischemic stroke.

Detection of copeptin in peripheral blood of patients with aneurysmal subarachnoid hemorrhage

Introduction

Copeptin has been proposed as a prognostic marker in acute illness. This study investigated the ability of copeptin to predict the disease outcome and cerebrovasospasm in the patients with aneurysmal subarachnoid hemorrhage.

Methods

In this retrospective study, 303 consecutive patients were included. Upon admission, plasma copeptin levels were measured by enzyme-linked immunosorbent assay. The end points were mortality after 1 year, in-hospital mortality, cerebrovasospasm and poor functional outcome (Glasgow Outcome Scale score of 1-3) after 1 year.

Results

Upon admission, plasma copeptin level in patients was statistically significantly higher than that in healthy controls. A multivariate analysis showed that plasma copeptin level was an independent predictor of poor functional outcome and mortality after 1 year, in-hospital mortality and cerebrovasospasm. A receiver operating characteristic curve showed that plasma copeptin level on admission predicted poor functional outcome and mortality after 1 year, in-hospital mortality and cerebrovasospasm of patients statistically significantly. The area under curve of the copeptin concentration was similar to those of World Federation of Neurological Surgeons (WFNS) score and modified Fisher score for the prediction of poor functional outcome and mortality after 1 year, and in-hospital mortality, but not for the prediction of cerebrovasospasm. In a combined logistic-regression model, copeptin improved the area under curve of WFNS score and modified Fisher score for the prediction of poor functional outcome after 1 year, but not for the prediction of mortality after 1 year, in-hospital mortality, and cerebrovasospasm.

Conclusions

Copeptin level is a useful, complementary tool to predict functional outcome and mortality after aneurysmal subarachnoid hemorrhage.

Usefulness of pre-operative copeptin concentrations to predict post-operative outcome after major vascular surgery

The aim of this study was to investigate whether preoperative determination of plasma copeptin levels in addition to plasma N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) could help improve risk stratification in patients who undergo major vascular surgery. One hundred ninety-eight consecutive patients who underwent major vascular surgery (58.6% infrainguinal aortic reconstruction, 23.7% abdominal aortic aneurysm surgery, 17.7% carotid endarterectomy) were included in this study. Patients were monitored for in-hospital and long-term (2-years) major adverse cardiac events, consisting of cardiac death, nonfatal myocardial infarction, and emergent coronary revascularization. Overall, 40 patients (20.2%) reached the primary end point, and most of these events occurred during the index hospital stay (n = 18 [45%]). In univariate Cox regression analysis, increasing concentrations of copeptin were significant determinants of outcome as a continuous variable (hazard ratio [HR] 1.012, p = 0.005) and as a dichotomized variable according to the recommended cutoff of 14.0 pmol/L (HR 4.116, p <0.001). Subgroup analyses revealed that especially patients at low estimated risk according to plasma NT-pro-BNP levels were at significantly higher risk for worse outcomes with higher copeptin levels (HR 5.983, p = 0.002). In multivariate Cox regression analysis, copeptin concentrations >14 pmol/L were significant independent predictors of outcome (HR 2.842, p = 0.002) in addition to type of surgery, history of myocardial infarction, elevated levels of cardiac troponin T, and NT-pro-BNP levels. In conclusion, the results of this study suggest that preoperative determination of this new biomarker could substantially improve prediction of perioperative and postoperative outcomes in vascular surgery patients.

The Sequential Organ Failure Assessment score and copeptin for predicting survival in ventilator-associated pneumonia

INTRODUCTION

Ventilator-associated pneumonia remains the most common nosocomial infection in the critically ill and contributes to significant morbidity. Eventual decisions regarding withdrawal or maximal therapy are demanding and rely on physicians' experience. Additional objective tools for risk assessment may improve medical judgement. Copeptin, reflecting vasopressin release, as well as the Sequential Organ Failure Assessment (SOFA) score, reflecting the individual degree of organ dysfunction, might qualify for survival prediction in ventilator-associated pneumonia. We investigated the predictive value of the SOFA score and copeptin in ventilator-associated pneumonia.

METHODS

One hundred one patients with ventilator-associated pneumonia were prospectively assessed. Death within 28 days after ventilator-associated pneumonia onset was the primary end point.

RESULTS

The SOFA score and the copeptin levels at ventilator-associated pneumonia onset were significantly elevated in nonsurvivors (P = .002 and P = .017, respectively). Both markers had different time courses in survivors and nonsurvivors (P < .001 and P = .006). Mean SOFA (average SOFA of 10 days after VAP onset) was superior in predicting 28-day survival as compared with SOFA and copeptin at ventilator-associated pneumonia onset (area under the curve, 0.90 vs 0.73 and 0.67, respectively).

CONCLUSIONS

The predictive value of serial-measured SOFA significantly exceeds those of single SOFA and copeptin measurements. Serial SOFA scores accurately predict outcome in ventilator-associated pneumonia.

Endogenous stress response in Tako-Tsubo cardiomyopathy and acute myocardial infarction

BACKGROUND

As the clinical, electrocardiographic and laboratory presentation of Tako-Tsubo cardiomyopathy (TTC) and acute myocardial infarction (AMI) is similar, both entities are in general only distinguishable by coronary angiography. The purpose of this study was to examine the endogenous stress response at presentation, quantified by the copeptin level, of patients with TTC and patients with AMI, as copeptin may be useful in the non-invasive differentiation between both diseases.

METHODS

We compared the endogenous stress response at initial presentation, quantified by the plasma copeptin levels, in 21 consecutive patients finally diagnosed with TTC and 21 patients finally diagnosed with AMI matched for sex and time since chest pain onset.

RESULTS

The prevalence of cardiovascular risk factors and initial cardiac troponin T levels were comparable in TTC and AMI. Copeptin levels were significantly lower in patients with TTC when compared to patients with AMI (median 4·8 [interquartile range, IQR 3·5-13·5] pM vs. 25·6 [IQR 12·1-63·9] pM, P = 0·002). The accuracy for diagnosing TTC as quantified by the area under the receiver operating characteristics curve was significantly higher for copeptin than for cardiac troponin T (0·782 vs. 0·549, P = 0·031). The optimal cut-off value for differentiation between TTC and AMI was found at a copeptin level of 7·8 pM (sensitivity 67% at a specificity of 86%, negative predictive value 72%, positive predictive value 82%).

CONCLUSIONS

The endogenous stress response, quantified by a novel sensitive biomarker, seems to be different in patients with TTC and AMI. Copeptin levels may be helpful in the non-invasive differentiation between TTC and AMI.

Inflammatory and neuroendocrine biomarkers of prognosis after ischemic stroke

Stroke is the third leading cause of mortality in the USA and one of the leading causes of severe morbidity. It is important to provide stroke patients and physicians with the most accurate prognostic information to optimize care and allocation of healthcare resources. Reliable prognostic markers available during the initial phase after acute stroke may aid clinical decision-making. Several interesting candidate biomarkers have been studied to address prognostic questions; this article will focus on selected inflammatory and neuroendocrine markers. The utility of a biomarker is defined by its ability to improve clinical decision-making and add timely information beyond that readily available from clinical examination and routine imaging. This aim has not been completely achieved yet for any biomarkers, but promising data are available and further studies are ongoing.

Copeptin and peroxiredoxin-4 independently predict mortality in patients with nonspecific complaints presenting to the emergency department

OBJECTIVES

Patients presenting to emergency departments (ED) with nonspecific complaints (NSCs) such as "not feeling well,""feeling weak,""being tired,""general deterioration," or other similar chief complaints that do not have a readily identifiable probable etiology are a common patient group at risk for adverse outcomes. Certain biomarkers, which have not yet been tested for prognostic value when applied to ED patients with NSCs, have emerged as useful tools for predicting prognosis in patients with a variety of diseases. This study tested the hypothesis that two of these novel markers, copeptin (a C-terminal portion of provasopressin) and/or peroxiredoxin-4 (Prx4), an enzyme that degrades hydrogen peroxide, singly or together are helpful in predicting death in the near term among patients presenting to the ED with NSCs.

METHODS

The Basel Non-specific Complaints (BANC) study is a delayed type cross-sectional diagnostic study with a prospective 30-day follow-up. ED patients with NSCs were consecutively enrolled. Patients with vital parameters out of the normal range were excluded. The primary endpoint of this study was the predictive value of copeptin and Prx4 for 30-day mortality in patients with NSCs. Measurement of both copeptin and Prx4 was performed in serum samples with sandwich immunoluminometric assays.

RESULTS

On follow-up at 30 days after ED presentation, 28 of 438 patients with NSC had died. Copeptin and Prx4 concentrations were significantly higher in nonsurvivors than in survivors (Kruskal-Wallis test, p = 0.0001 and p < 0.0001, respectively). In univariate models, Prx4 (likelihood ratio [LR] χ(2) = 22.24, p < 0.00001, concordance index [C-index] = 0.749) and copeptin (LR χ(2) = 16.98, p = 0.00004, C-index = 0.724) were both predictive of 30-day mortality, and elevated levels were associated with an increased mortality. The bivariable model, which included both Prx4 and copeptin (LR χ(2) = 28.22, p < 0.00001, C-index = 0.783), allows a significantly better prediction than the univariate Prx4 (p = 0.00025) and copeptin models (p = 0.00099), respectively. Both biomarkers provided independent and additional information to clinical risk scores (Katz Activities of Daily Living [ADL] and Charlson Comorbidity Index [CCI], all p < 0.0005).

CONCLUSIONS

Copeptin and Prx4 are new prognostic markers in patients presenting to the ED with NSCs. Copeptin and Prx4 might be valuable tools for risk stratification and decision-making in this patient group.

Copeptin - is There a Role for Another Cardiac Biomarker?

The discovery and development of new biomarkers continues to be a promising field. Since cardiovascular disease remains the principal cause of death in the developed countries, this is the area in which novel biomarkers have been most extensively evaluated. Arginine vasopressin (AVP or antidiuretic hormone) is one of the key hormones in the human body involved in cardiovascular homeostasis. It has so far escaped introduction into the routine clinical laboratory due to technical difficulties and pre-analytical errors. Copeptin, the C-terminal part of the AVP precursor peptide, was found to be a stable and sensitive surrogate marker for AVP release. During the past years, copeptin measurement has been shown to be of interest in a variety of clinical indications, including cardiovascular diseases such as heart failure, myocardial infarction, and stroke. This review summarizes the recent progress in the diagnostic use of plasma copeptin in cardiovascular diseases.

Mannose-binding lectin deficiency is associated with smaller infarction size and favorable outcome in ischemic stroke patients

Background

The Mannose-binding lectin (MBL) pathway of complement plays a pivotal role in the pathogenesis of ischemia/reperfusion (I/R) injury after experimental ischemic stroke. As comparable data in human ischemic stroke are limited, we investigated in more detail the association of MBL deficiency with infarction volume and functional outcome in a large cohort of patients receiving intravenous thrombolysis or conservative treatment.

Methodology/Principal Findings

In a post hoc analysis of a prospective cohort study, admission MBL concentrations were determined in 353 consecutive patients with an acute ischemic stroke of whom 287 and 66 patients received conservative and thrombolytic treatment, respectively. Stroke severity, infarction volume, and functional outcome were studied in relation to MBL concentrations at presentation to the emergency department. MBL levels on admission were not influenced by the time from symptom onset to presentation (p = 0.53). In the conservative treatment group patients with mild strokes at presentation, small infarction volumes or favorable outcomes after three months demonstrated 1.5 to 2.6-fold lower median MBL levels (p = 0.025, p = 0.0027 and p = 0.046, respectively) compared to patients with more severe strokes. Moreover, MBL deficient patients (<100 ng/ml) were subject to a considerably decreased risk of an unfavorable outcome three months after ischemic stroke (adjusted odds ratio 0.38, p<0.05) and showed smaller lesion volumes (mean size 0.6 vs. 18.4 ml, p = 0.0025). In contrast, no association of MBL concentration with infarction volume or functional outcome was found in the thrombolysis group. However, the small sample size limits the significance of this observation.

Conclusions

MBL deficiency is associated with smaller cerebral infarcts and favorable outcome in patients receiving conservative treatment. Our data suggest an important role of the lectin pathway in the pathophysiology of cerebral I/R injury and might pave the way for new therapeutic interventions.