The influence of anaemia on stroke prognosis and its relation to N-terminal pro-brain natriuretic peptide

Association between baseline hemoglobin level and early neurological deterioration after intravenous thrombolysis in patients with acute ischemic stroke

OBJECTIVES

To investigate the association between baseline hemoglobin level and early neurologic deterioration (END) after intravenous thrombolysis in patients with acute ischemic stroke (AIS).

METHODS

Data of AIS patients who received intravenous thrombolytic therapy at multiple hospitals across the country between January 2017 and July 2020 were collected from the online database Acute Stroke Patients for Stroke Management Quality Evaluation (CASE-Ⅱ, NCT04487340). Binary logistic regression analysis was used to study the factors affecting the occurrence of END after intravenous thrombolytic therapy, and the correlation between baseline hemoglobin level and END was investigated by limiting cubic spline curve analysis.

RESULTS

A total of 8162 patients were included. Patients with END had lower baseline hemoglobin levels (136 and 140 g/L, P<0.01) and higher rates of anemia (24.2% and 16.9%, P<0.01) compared with non-END patients. Binary logistic regression analysis showed that baseline hemoglobin level (OR=0.995, 95%CI: 0.991-0.999, P<0.05) and anemia (OR=1.238, 95%CI: 1.055-1.454, P<0.01) were independently correlated with the occurrence of END after intravenous thrombolysis in AIS patients. Restricted cubic spline regression showed that there was a U-shaped relationship between hemoglobin level and the risk of END after intravenous thrombolysis in AIS patients (P<0.01), although this relationship was only significant in male patients (P<0.05) and not in female patients (P>0.05).

CONCLUSIONS

There is a correlation between baseline hemoglobin level and the risk of END in AIS patients after intravenous thrombolysis, especially in male patients, in whom both lower and higher hemoglobin level may increase the risk of END.

A 6-month prognostic nomogram incorporating hemoglobin level for intracerebral hemorrhage in younger adults

OBJECTIVE

Intracerebral hemorrhage (ICH) is the second most common subtype of stroke, with high mortality and morbidity. At present, there are no effective 6-month prognostic markers, particularly for younger patients. The aim of this research was to construct a new valuable prognostic nomogram model incorporating haemoglobin levels for adult patients with ICH.

METHODS

Patients aged between 18 and 50 presenting with intracerebral haemorrhage at the Tongji Hospital, Tongji Medical College of Huazhong University of Science and Technology between January 1st 2012 and December 31st 2018 were included in this retrospective study. Independent factors of prognosis were identified by univariate and multivariate logistic regression analyses, and a new nomogram model was constructed and validated. The clinical value of the nomogram model was subsequently explored utilizing decision curve analysis and clinical impact curves.

RESULTS

In total, 565 patients were enrolled in this study, 117 (20.7%) of whom developed an unfavourable prognosis. Infratentorial lesion (adjusted odds ratio [aOR] = 3.708, 95% confidence interval [CI], 1.490-9.227; P = 0.005) was the most significant unfavourable outcome. Age ([aOR] = 1.054; 95% CI, 1.014-1.096; P = 0.008), hematoma volume (aOR = 1.014, 95% CI, 1.002-1.027; P = 0.024), haemoglobin (aOR = 0.981, 95% CI, 0.969-0.993; P = 0.002), blood glucose (aOR = 1.135, 95% CI, 1.037-1.241; P = 0.005) and NIHSS (aOR = 1.105, 95% CI, 1.069-1.141; P < 0.001) were independent risk factors. Based on these 6 factors, the nomogram can be employed to predict early functional prognosis with high accuracy (AUC 0.791). Decision curve analysis and clinical impact curves showed an increased net benefit for utilizing the nomogram.

CONCLUSION

The haemoglobin level at admission may be an easily overlooked factor in clinical work. This new nomogram model could be a promising and convenient tool to predict the early functional prognosis of adults with ICH. More prospective multicentre studies are needed to validate these findings.

Factors associated with early improvement after intravenous thrombolytic treatment in acute ischemic stroke

OBJECTIVE

: The aim of this study was to determine the factors associated with early neurological improvement (ENI) in patients who experienced acute ischemic stroke and were treated with intravenous recombinant tissue plasminogen activator (IV rt-PA), and determine the relationship with the outcome at the first control.

METHOD

: This study included 377 patients who were treated with IV rt-PA in Izmir Dokuz Eylül University Hospital between January 2010 and October 2018. ENI was defined as a 4 or more improvement in the National Institutes of Health Stroke Scale (NIHSS) score in the first hour, the twenty-fourth hour and the seventh day when compared to the pretreatment phase. The modified Rankin Scale (mRS) 0-1 score was defined as 'very good outcome'.

RESULTS

: The basal NIHSS (p=0.003, p=0.003, p=0.022) was high in the first hour, twenty-fourth hour, and seventh day ENI groups. Blood urea nitrogen (BUN) level was low in the first- and twenty-fourth-hour ENI groups (p=0.007, p=0.020). Furthermore, admission glucose was low at the twenty-fourth hour and on the seventh day ENI groups (p=0.005, p=0.048). A high infarct volume was observed on magnetic resonance imaging (MRI) at the twenty-fourth hour and on the seventh day non-ENI groups (p= <0.001, p= <0.001).

CONCLUSION

: Management of factors associated with ENI and determination of treatment strategies accordingly are important for obtaining a better clinical outcome. It can help quickly select patients, who, even though they will not respond to rt-PA, may be appropriate candidates for bridging therapy.

Hemoglobin concentration does not impact 3-month outcome following acute ischemic stroke

BACKGROUND

There is uncertainty regarding the effect of anemia and red blood cell transfusion on functional outcome following acute ischemic stroke. We studied the relationship of hemoglobin parameters and red cell transfusion with post stroke functional outcome after adjustment for neurological severity and medical comorbidities.

METHODS

Retrospective cohort study of 536 patients discharged with a diagnosis of ischemic stroke from a tertiary care hospital between January 2012 and April 2015. Hemoglobin level at hospital admission, lowest recorded value during hospitalization (nadir), delta hemoglobin (admission minus nadir), red cell transfusion during hospitalization were noted. Charlson Comorbidity Index (CCI) was computed as a summary measure of medical comorbidities. A multivariable logistic regression model was used to determine risk-adjusted odds of unfavorable outcome, defined as a modified Rankin Score of > 2.

RESULTS

Anemia was present on hospital admission in 31% of patients. Forty five percent of patients had unfavorable outcome. In the univariable analysis increasing age, admission National Institutes of Health Stroke Scale (NIHSS), CCI, nadir hemoglobin, delta hemoglobin and blood transfusion were associated with unfavorable outcome. In the multivariable model, only increasing age, CCI and NIHSS remained associated with unfavorable outcome. No quadratic association was found on repeating the model to identify a possible U-shaped relationship of hemoglobin with outcome.

CONCLUSIONS

Our findings contradict prior observational studies and highlight an area of clinical equipoise regarding the optimal management of anemia in patients hospitalized for ischemic stroke. This uncertainty could be addressed with appropriately designed clinical trials.

Association between admission haematocrit and mortality among men with acute ischaemic stroke

Objective

Anaemia is associated with higher mortality among patients with non-stroke cardiovascular conditions; less is known regarding the relationship between anaemia and mortality among patients with acute ischaemic stroke.

Methods

Medical records were abstracted for n=3965 veterans from 131 Veterans Health Administration facilities who were admitted with ischaemic stroke in fiscal year 2007. Haematocrit values within 24 hours of admission were classified as ≤27%, 28%–32%, 33%–37%, 38%–42%, 43%–47% or ≥48%. Multivariate logistic regression was used to examine the relationship between anaemia and in-hospital, 30-day, 6-month and 1-year mortality, adjusting for age, medical comorbidities, modified Acute Physiology and Chronic Health Evaluation-III and stroke severity. Impact factors were calculated to standardise comparisons between haematocrit tier and other covariates.

Results

Among n=3750 patients included in the analysis, the haematocrit values were ≤27% in 2.1% (n=78), 28%–32% in 6.2% (n=234), 33%–37% in 17.9% (n=670), 38%–42% in 36.4% (n=1366), 43%–47% in 28.2% (n=1059) and ≥48% in 9.1% (n=343). Patients with haematocrit ≤27%, compared with patients in the 38%–42% range, were more likely to have died across all follow-up intervals, with statistically significant adjusted ORs (aORs) ranging from 2.5 to 3.5. Patients with polycythaemia (ie, haematocrit ≥48%) were at increased risk of in-hospital mortality (aOR=2.9; 95% CI 1.4 to 6.0), compared with patients with mid-range admission haematocrits. Pronounced differences between patients receiving and not receiving blood transfusion limited our ability to perform a propensity analysis. Impact factors in the 1-year mortality model were 0.46 (severe anaemia), 0.06 (cancer) and 0.018 (heart disease).

Conclusions

Anaemia is independently associated with an increased risk of death throughout the first year post stroke; high haematocrit is associated with early poststroke mortality. Severe anaemia is associated with 1-year mortality to a greater degree than cancer or heart disease. These data cannot address the question of whether interventions targeting anaemia might improve patient outcomes.

Moderate to Severe Anemia Is Associated with Poor Functional Outcome in Acute Stroke Patients Treated with Mechanical Thrombectomy

Background

Anemia will negatively affect cerebral collaterals and penumbra. Eventually, it may cause worse clinical outcomes and even increase mortality rates in stroke patients. Anemia has recently been suggested to be an independent risk factor for ischemic stroke. Therefore, we aimed to investigate the effects of the presence of anemia on clinical outcomes in ischemic stroke patients undergoing mechanical thrombectomy.

Methods

This was a retrospective study involving the prospectively and consecutively collected data of 90 adult patients between January 2015 and August 2016. Hemoglobin (Hb) cutoff levels were accepted as 12 g/dL for women and 13 g/dL for men. Patients having anemia were further divided into three subgroups as severe anemia (Hb <8 g/dL for both genders), moderate anemia (Hb <10 g/dL for both genders), and mild anemia (Hb <13 g/dL for men and Hb <12 g/dL for women).

Results

Forty of the subjects (44.4%) had anemia. Moderate anemia was detected in 14 out of 90 patients (15.5%) and severe anemia was found in only four of them (4.4%). Poor functional outcome (mRS 3-6) was similar in both anemic and non-anemic patients (37.5% vs. 38%, respectively, p = 0.08), but poor functional outcome was found to be statistically significant with severe anemic group (Hb <8 mg/dL) (p = 0.003). In multiple logistic regression analysis, moderate and severe anemia has been found to increase the mortality (p = 0.032).

Conclusions

Our study demonstrated a poor functional outcome only in moderate to severe anemic patients. Clinicians should keep in mind the negative effect of moderate to severe anemia in the clinical course of acute stroke patients treated with mechanical thrombectomy.

Impact of Hemoglobin Levels and Anemia on Mortality in Acute Stroke: Analysis of UK Regional Registry Data, Systematic Review, and Meta-Analysis

BACKGROUND

The impact of hemoglobin levels and anemia on stroke mortality remains controversial. We aimed to systematically assess this association and quantify the evidence.

METHODS AND RESULTS

We analyzed data from a cohort of 8013 stroke patients (mean±SD, 77.81±11.83 years) consecutively admitted over 11 years (January 2003 to May 2015) using a UK Regional Stroke Register. The impact of hemoglobin levels and anemia on mortality was assessed by sex-specific values at different time points (7 and 14 days; 1, 3, and 6 months; 1 year) using multiple regression models controlling for confounders. Anemia was present in 24.5% of the cohort on admission and was associated with increased odds of mortality at most of the time points examined up to 1 year following stroke. The association was less consistent for men with hemorrhagic stroke. Elevated hemoglobin was also associated with increased mortality, mainly within the first month. We then conducted a systematic review using the Embase and Medline databases. Twenty studies met the inclusion criteria. When combined with the cohort from the current study, the pooled population had 29 943 patients with stroke. The evidence base was quantified in a meta-analysis. Anemia on admission was found to be associated with an increased risk of mortality in both ischemic stroke (8 studies; odds ratio 1.97 [95% CI 1.57-2.47]) and hemorrhagic stroke (4 studies; odds ratio 1.46 [95% CI 1.23-1.74]).

CONCLUSIONS

Strong evidence suggests that patients with anemia have increased mortality with stroke. Targeted interventions in this patient population may improve outcomes and require further evaluation.

Anemia increases the mortality risk in patients with stroke: A meta-analysis of cohort studies

The impact of anemia on the outcome of patients with stroke remains inconsistent. We performed a meta-analysis of cohort studies to assess the mortality risk in stroke patients with and without anemia. Systematic searches were conducted in the PubMed, China National Knowledge Infrastructure, Web of Science and Wanfang databases to identify relevant studies from inception to November 2015. The estimated odds ratio with a 95% confidence interval was pooled. subgroup analyses and sensitivity analyses were also conducted. We used Begg’s funnel plot and Egger’s test to detect the potential publication bias. Thirteen cohort studies with a total of 19239 patients with stroke were included in this meta-analysis. The heterogeneity among studies was slight (I² = 59.0%, P = 0.031). The results from a random-effect model suggest that anemia is associated with an increased mortality risk in patients with stroke (adjusted odds ratio = 1.39, 95% confidence interval: 1.22–1.58, P < 0.001). The subgroup analyses are consistent with the total results. This meta-analysis of 13 cohort studies finds that anemia increases the mortality risk in patients with stroke. Future studies should perform longer follow-up to confirm this finding and explore its possible mechanism.

Hepcidin Levels Are Increased in Patients with Acute Ischemic Stroke: Preliminary Report

BACKGROUND

Our current understanding of iron balance in acute ischemic stroke (AIS) is still limited. The objective of this study was to evaluate levels of iron homeostasis proteins-hepcidin (25-amino acid form) and soluble hemojuvelin (sHJV) together with hepcidin/sHJV ratio (Hepc/sHJV) and soluble transferrin receptor (sTfR) in patients with AIS. In addition, the effect of timing of blood collection, type of stroke treatment, and scores on the National Institutes of Health Stroke Scale were investigated.

METHODS

Participants comprised 31 patients diagnosed with AIS and 20 matched healthy controls. Venous blood samples were drawn on the first day and on the seventh day after stroke onset. Individuals who had experienced a stroke were subdivided according to type of treatment (thrombolysis group, n = 12 versus nonthrombolysis group, n = 19). Plasma hepcidin, sHJV, and sTfR levels were determined by the enzyme-linked immunosorbent assay method.

RESULTS

We found that plasma hepcidin levels were significantly higher in ischemic stroke patients compared with the control group (median, 19.82 versus 12.62 ng/mL, P = .04). Furthermore, levels of hepcidin on the seventh day (1 week after diagnosis) were significantly higher in patients treated with thrombolysis than in patients not treated with thrombolysis (median, 22.16 versus 16.21 ng/mL, P = .04).

CONCLUSIONS

The study provides evidence that AIS is associated with increased hepcidin levels. Stroke treatment may have an influence on hepcidin synthesis.

The impact of anemia on the course and short-term prognosis in patients with first ever ischemic stroke

BACKGROUND

Anemia is the risk factor for cerebrovascular events. The aim of this study was to evaluate the prevalence of anemia among patients with first-ever stroke and its impact on neurological state in the acute phase of the disease and the degree of disability in short-term follow-up.

PATIENTS AND METHODS

The prospective study included 107 patients aged 72.81 ± 11.12 with the first-ever stroke. Each patient underwent CT of the head and blood tests, including Hb concentration on the first day of hospitalization. We have analyzed the neurological state on the first day of stroke by NIHSS and the functional status on the 14th day after the onset of stroke by mRankin scale in patients with and without anemia. Patients with anemia were additionally divided according to Hb level (less or over 11g/dl).

RESULTS

Patients with Hb≤ 11g/dl significantly more often achieved a score of 4-5 points on mRankin scale on the 14th day of stroke compared to patients with anemia and Hb>11g/dl. Independent predictors of a worse functional status on the 14th day of stroke in patients with anemia include the neurological state on the 1st day and the hemispheric location of stroke; an independent predictor of death was the neurological state on the 1st day of onset.

CONCLUSION

Mild anemia did not influence significantly the neurological condition in acute phase of stroke but worsened the functional status in subacute phase of stroke. The neurological state on the first day of stroke and the hemispheric location of cerebral ischemia are independent factors of poor prognosis in patients with anemia in short-term follow-up.

Blood transfusion practices in neuroanaesthesia

Neuroanaesthesia practice is associated with risk of significant blood loss resulting in anaemia in the intraoperative and postoperative period. The transfusion triggers in a neurologically injured brain are not clearly defined. Both a low haematocrit and a high haematocrit have not shown any improvement in the outcome. Transfusion of red blood cells may improve the cerebral oxygenation on neurophysiological monitors. However, these benefits have not been translated into clinical practice. Transfusion in subarachnoid haemorrhage leads to increased incidence of vasospasm and a poor outcome. Restrictive transfusion strategy is seen to have a lower incidence of pneumonia, urinary tract infection, bacteremia and septic shock in severe head injury. Current evidence suggests that a haemoglobin (Hb) level of <7 g/dl may be deleterious to the neurosurgical population. Target Hb of 8-9 g/dl may be desirable intraoperatively. Different transfusion triggers may hold true for different neurosurgical pathologies.

Anemia on admission predicts short- and long-term outcomes in patients with acute ischemic stroke

BACKGROUND

It is still debatable whether anemia predicts stroke outcome.

AIM

To describe the characteristics of patients with acute ischemic stroke (AIS) and anemia and identify whether hemoglobin status on admission is a prognostic factor of AIS outcome.

METHODS

All 2439 patients of the Acute Stroke Registry and Analysis of Lausanne (ASTRAL) between January 2003 and June 2011 were selected. Demographics, risk factors, prestroke treatment, clinical, radiological and metabolic variables in patients with and without anemia according to the definition of the World Health Organization were compared. Functional disability and mortality were recorded up to 12 months from admission.

RESULTS

Anemic patients (17.5%) were older, had lower body mass index, higher rates of coronary artery disease (CAD), atrial fibrillation, diabetes mellitus and peripheral artery disease. Anemia was associated with more severe stroke manifestations, lower systolic and diastolic blood pressure measurements, worse estimated glomerular filtration rate and elevated C-reactive protein concentrations upon admission and with increased modified Rankin scores during the follow-up. Anemic patients had higher 7-day, 3-month and 12-month mortality, which was associated with hemoglobin status and other factors, including age, CAD, stroke severity, and baseline C-reactive levels. Hemoglobin levels were inversely associated with recurrent stroke and mortality throughout the 12-month follow-up.

CONCLUSION

Anemia is common among AIS patients and is associated with cardiovascular comorbidities. Low hemoglobin status independently predicts short and long-term mortality.

Hemoglobin is associated with retinal vascular fractals in type 1 diabetes patients

PURPOSE

Retinal vascular fractal dimension, a measure of the density of the retinal vasculature, has been suggested as a marker of systemic microvascular disorders in diabetes. As hemoglobin concentration is tightly related to vascular physiology and hypoxia, the hypothesis was that hemoglobin concentration would be associated with retinal vascular fractals in a relevant population.

METHODS

In a cross-sectional study of 204 long-term type 1 diabetes patients from a population-based cohort, retinal digital photos were captured and graded for fractal dimension (Df) by International Retinal Imaging Software - Fractal (IRIS-Fractal). Df was calculated from a disc-centered retinal photo from the right eye. Hemoglobin concentrations were measured using routine equipment.

RESULTS

Of 175 patients with gradable images, median age was 57.7 years and median duration of diabetes was 42 years. Median retinal Df was 1.4606 (inter-quartile range 0.0264). A positive correlation was found between hemoglobin concentration and retinal vascular Df (r = 0.23, p = 0.0018). In a multiple linear regression model, Df was associated with hemoglobin (coefficient 0.0054 per 1.0 mmol/L increase in hemoglobin, p = 0.01) and age (coefficient -0.0046 for each 10-year increase in age, p = 0.04).

CONCLUSION

Hemoglobin correlated independently with retinal vascular fractals indicating a relationship between hemoglobin availability and retinal vascular structure.

Anemia on admission increases the risk of mortality at 6 months and 1 year in hemorrhagic stroke patients in China

BACKGROUND

The relationship between anemia and intracerebral hemorrhage is not clear. We investigated the associations between anemia at the onset and mortality or dependency in patients with intracerebral hemorrhage (ICH) registered at the China National Stroke Registry (CNSR).

METHODS

The CNSR recruited consecutive patients with diagnoses of ICH in 2007-2008. Their vascular risk factors, clinical presentations, and outcomes were recorded. The mortality and dependency at 1, 3, and 6 months and at 1 year were compared between ICH patients with and without anemia. A favorable outcome was defined as a modified Rankin Scale (mRS) score of 2 or less and a poor outcome as an mRS score of 3 or more. Multivariable logistic regression was performed to analyze the association between anemia and the 2 outcomes after adjusting for age, gender, body mass index, history of smoking and heavy drinking, National Institutes of Health Stroke Scale score on admission, random glucose value on admission, and hematoma volume.

RESULTS

Anemia was identified in 484 (19%) ICH patients. Compared with ICH patients without anemia, patients with anemia had no difference in mortality rate at discharge and at 1 month. The rate of mortality at 3 months, 6 months, 1 year, and dependency at 1 year were significantly higher for those patients with anemia than those without (P<.05, P<.001, P<.001, and P<.05, respectively). After adjusting for potential confounders, anemia was an independent risk factor for death at 6 months and 1 year (adjusted odds ratio [OR]=1.338, 95% confidence interval 1.01-1.78, and adjusted OR=1.326, 95% confidence interval 1.00-1.75) in ICH patients.

CONCLUSIONS

Anemia independently predicted mortality at 6 months and 1 year after the initial episode of intercerebral hemorrhage.

Two cases of acute ischemic stroke associated with iron deficiency anemia due to bleeding from uterine fibroids in middle-aged women

We herein report two cases of acute ischemic stroke associated with iron deficiency anemia (IDA) due to bleeding from uterine fibroids. Anemia is not generally recognized as a risk factor for stroke. The physiological mechanisms that may factor in the development of ischemic stroke in patients with IDA include thrombocytosis, hypercoagulable state, and anemic hypoxia. In our two cases, IDA was considered to be the cause of ischemic stroke because all other known causes of stroke were ruled out. In patients with ischemic stroke due to anemia, early treatment of the anemia is important to prevent stroke recurrence.

Impact of both ends of the hemoglobin range on clinical outcomes in acute ischemic stroke

BACKGROUND AND PURPOSE

Although both ends of the hemoglobin range may negatively influence clinical outcomes in acute ischemic stroke, most studies have examined the linear relationship or focused on the lower end of the range. Furthermore, it is unclear whether hemoglobin concentrations at different time points during hospitalization correlate with clinical outcomes in the same manner.

METHODS

We identified 2681 consecutive patients with acute ischemic stroke from a prospective stroke registry database and grouped them into hemoglobin concentration quintiles using the following 5 indices: initial, nadir, time-averaged, discharge hemoglobin, and hemoglobin drop. To examine the effect of both ends of hemoglobin range, the third quintile was selected as a reference category except for hemoglobin drop, for which the first quintile was used. As outcome variables, 3-month modified Rankin Scale as an ordinal scale and 3-month mortality were used.

RESULTS

With respect to higher modified Rankin Scale scores, the adjusted odds ratios and 95% confidence intervals of the first quintiles of initial, nadir, time-averaged, and discharge hemoglobin were 1.74 (1.31-2.31), 2.64 (2.09-3.33), 1.81 (1.42-2.30), and 1.65 (1.29-2.13), respectively. The opposite ends of these hemoglobin indices were not significantly associated. The adjusted odds ratio of the fifth quintile of hemoglobin drop (greatest hemoglobin drop) was 2.09 (1.51-2.89). The mortality analysis showed similar results except for initial hemoglobin.

CONCLUSIONS

In acute ischemic stroke, poor outcome was related to the lower but not the higher end of the hemoglobin range, regardless of when and how hemoglobin concentrations were measured.

Anaemia on Admission is Associated with More Severe Intracerebral Haemorrhage and Worse Outcomes

Background

Lower haemoglobin levels may impair cerebral oxygen delivery and threaten tissue viability in the setting of acute brain injury. Few studies have examined the association between haemoglobin levels and outcomes after spontaneous intracerebral haemorrhage.

Aims

We evaluated whether anaemia on admission was associated with greater intracerebral haemorrhage severity and worse outcome.

Methods

Consecutive patients with spontaneous intracerebral haemorrhage were analyzed from the Registry of the Canadian Stroke Network. Admission haemoglobin was related to stroke severity (using the Canadian Neurological Scale), modified Rankin score at discharge, and one-year mortality. Adjustment was made for potential confounders including age, gender, medical history, warfarin use, glucose, creatinine, blood pressure, and intraventricular haemorrhage.

Results

Two thousand four hundred six patients with intracerebral haemorrhage were studied of whom 23% had anaemia (haemoglobin <120 g/l) on admission, including 4% with haemoglobin <100 g/l. Patients with anaemia were more likely to have severe neurological deficits at presentation [haemoglobin ≤100 g/l, adjusted odds ratio 4·04 (95% confidence interval 2·39, 6·84); haemoglobin 101–120 g/l, adjusted odds ratio 1·93 (95% confidence interval 1·43, 2·59), both P < 0·0001]. In nonanticoagulated patients, severe anaemia was also associated with poor outcome (modified Rankin score 4–6) at discharge [haemoglobin ≤100 g/l, adjusted odds ratio 2·42 (95% confidence interval 1·07–5·47), P= 0·034] and increased mortality at one-year [haemoglobin ≤100 g/l, adjusted hazard ratio 1·73 (95% confidence interval 1·22–2·45), P = 0·002].

Conclusions

Anaemia on admission is associated with greater intracerebral haemorrhage severity and worse outcomes. The utility of transfusion remains unclear in this setting.

Risk Factor of Visuospatial Neglect: A Study of Association Between Visuospatial Neglect and Anemia

Objective

To investigate the correlation between visuospatial neglect and anemia in patients with right cerebral infarction, as well as to identify the risk factor of neglect and furnish preliminary data on rehabilitation management.

Methods

The line bisection test and Albert test were conducted on subjects with right cerebral infarction in order to analyze neglect severity. Multiple linear regression analysis was conducted to investigate correlation between neglect severity and hemoglobin and hematocrit level. Logistic regression analysis was applied to identify the risk factor of neglect.

Results

Visuospatial neglect was observed in 33 subjects out of 124. Hemoglobin and hematocrit were not directly correlated with visuospatial neglect severity, whereas infarct size was directly correlated. Subjects with visuospatial neglect were characterized by a large infarct size, a low score in the Mini-Mental State Examination and long hospital stay.

Conclusion

In this study, visuospatial neglect was found to be uncorrelated with anemia. It implies that emphasis should be placed on the early detection of anemia and neglect in patients with left hemiplegia, the formulation of respective therapeutic plans and improvement of prognosis. The study found that the possibility of a visuospatial neglect occurrence increases with infarct size. In this regard, it is required that visuospatial neglect was detected and treated in the earliest possible stage, notwithstanding the difficulty that lies in the precise measurement of the severity.

A cohort study of patients with anemia on admission and fatality after acute ischemic stroke

Reduced blood hemoglobin levels may impair oxygen delivery to the brain and hinder neurological improvement. We prospectively registered consecutively hospitalized Chinese patients with acute ischemic stroke within 24 hours of symptom onset to investigate whether anemia on admission influences case fatality and functional outcome of acute ischemic stroke at 12 months. Anemia was defined as a blood hemoglobin level of < 120 g/L for women, and < 130 g/L for men. We also performed a meta-analysis of the current cohort and previously published studies. We included 1176 patients, of whom 351 patients (29.8%) had anemia. Age (odds ratio [OR]=1.02, 95% confidence interval [CI]: 1.01-1.03), history of hemorrhagic stroke (OR=3.34, 95% CI: 1.17-9.56), alcohol consumption (OR=0.59, 95% CI: 0.38-0.92), and estimated glomerular filtration rate < 60 mL/minute per 1.73 m(2) (OR=1.34, 95% CI: 1.00-1.80) were the independent predictors of anemia. After adjustment for potential confounders, anemia on admission was shown to be an independent predictor of death at discharge and at 12 months (OR=1.66, 95% CI, 1.08-2.56; OR=1.56, 95% CI, 1.05-2.31). A meta-analysis of six included studies involving 3810 participants confirmed that anemia on admission was an independent predictor of death at the end of follow-up (OR=1.67, 95% CI, 1.25-2.08). Further studies are required to confirm these findings.

Reduced hydration status characterized by disproportionate elevation of blood urea nitrogen to serum creatinine among the patients with cerebral infarction

The significance of fluid metabolism among the patients with cerebral infarction has barely mentioned in the literature despite the several reports suggesting the potential risk of reduced hydration status for the development of cerebral infarction. The aim of the this study is to explore the validity of the presumable relationship between hydration status and cerebral infarction. Ninety-seven patients with cerebral infarction from April 1, 2008 to March 31, 2009 were retrospectively investigated, and their hydration status were evaluated by using several clinical parameters such as a blood urea nitrogen to serum creatinine (BUN/Cr) ratio of >25 and plasma osmolality. Subjects with active infection, congestive heart failure, hepatic failure, gastrointestinal bleeding, or a malignancy were excluded since these conditions should modulate the absolute value of BUN/Cr ratio without a change in hydration status. Twenty-eight patients (29%) were considered as having reduced hydration status. The BUN/Cr ratio decreased significantly after the initiation of medical support (median 21.3; IR: 18.1-24.6), including oral or parenteral fluid supplementation, in comparison to the values at the time of patient admission (median 30.0; IR: 26.8-40.7; p<0.0001). Similar decreases were also observed in the hematocrit, hemoglobin, and plasma osmolality. The group considered to have reduced hydration status had a significantly higher prevalence of cardioembolic stroke than the other subjects. The hydration status may be a contributing factor to subtypes of cerebral infarction. Whether our findings are also the case with overall patients with cerebral infarction should be evaluated in greater detail.

Low hemoglobin is associated with poor functional outcome after non-traumatic, supratentorial intracerebral hemorrhage

Introduction

The impact of anemia on functional outcome and mortality in patients suffering from non-traumatic intracerebral hemorrhage (ICH) has not been investigated. Here, we assessed the relationship between hemoglobin (HB) levels and clinical outcome after ICH.

Methods

One hundred and ninety six patients suffering from supratentorial, non-traumatic ICH were extracted from our local stroke database (June 2004 to June 2006). Clinical and radiologic computed tomography data, HB levels on admission, mean HB values and nadir during hospital stay were recorded. Outcome was assessed at discharge and 3 months using the modified Rankin score (mRS).

Results

Forty six (23.5%) patients achieved a favorable functional outcome (mRS ≤ 3) and 150 (76.5%) had poor outcome (mRS 4 - 6) at discharge. Patients with poor functional outcome had a lower mean HB (12.3 versus 13.7 g/dl, P < 0.001) and nadir HB (11.5 versus 13.0 g/dl, P < 0.001). Ten patients (5.1%) received red blood cell (RBC) transfusions. In a multivariate logistic regression model, the mean HB was an independent predictor for poor functional outcome at three months (odds ratio (OR) 0.73, 95% confidence interval (CI) 0.58-0.92, P = 0.007), along with National Institute of Health Stroke Scale (NIHSS) at admission (OR 1.17, 95% CI 1.11 - 1.24, P < 0.001), and age (OR 1.08, 95% CI 1.04 - 1.12, P < 0.001).

Conclusions

We report an association between low HB and poor outcome in patients with non-traumatic, supratentorial ICH. While a causal relationship could not be proven, previous experimental studies and studies in brain injured patients provide evidence for detrimental effects of anemia on brain metabolism. However, the potential risk of anemia must be balanced against the risk of harm from red blood cell infusion.

Anemia status, hemoglobin concentration and outcome after acute stroke: a cohort study

BACKGROUND

In the setting of an acute stroke, anemia has the potential to worsen brain ischemia, however, the relationship between the entire range of hemoglobin to long-term outcome is not well understood.

METHODS

We examined the association between World Health Organization-defined admission anemia status (hemoglobin<13 in males, <12 g/dl in women) and hemoglobin concentration and 1-year outcome among 859 consecutive patients with acute stroke (ischemic or intracerebral hemorrhage).

RESULTS

The mean baseline hemoglobin concentration was 13.8 +/- 1.7 g/dl (range 8.1 - 18.7). WHO-defined anemia was present in 19% of patients among both women and men. After adjustment for differences in baseline characteristics, patients with admission anemia had an adjusted OR for all-cause death at 1-month of 1.90 (95% CI, 1.05 to 3.43) and at 1-year of 1.72 (95% CI, 1.00 to 2.93) and for the combined end-point of disability, nursing facility care or death of 2.09 (95% CI, 1.13 to 3.84) and 1.83 (95% CI, 1.02 to 3.27) respectively. The relationship between hemoglobin quartiles and all-cause death revealed a non-linear association with increased risk at extremes of both low and high concentrations. In logistic regression models developed to estimate the linear and quadratic relation between hemoglobin and outcomes of interest, each unit increment in hemoglobin squared was associated with increased adjusted odds of all-cause death [at 1-month 1.06 (1.01 to 1.12; p = 0.03); at 1-year 1.09 (1.04 to 1.15; p < 0.01)], confirming that extremes of both low and high levels of hemoglobin were associated with increased mortality.

CONCLUSIONS

WHO-defined anemia was common in both men and women among patients with acute stroke and predicted poor outcome. Moreover, the association between admission hemoglobin and mortality was not linear; risk for death increased at both extremes of hemoglobin.

Anemia and red blood cell transfusion in neurocritical care

INTRODUCTION

Anemia is one of the most common medical complications to be encountered in critically ill patients. Based on the results of clinical trials, transfusion practices across the world have generally become more restrictive. However, because reduced oxygen delivery contributes to 'secondary' cerebral injury, anemia may not be as well tolerated among neurocritical care patients.

METHODS

The first portion of this paper is a narrative review of the physiologic implications of anemia, hemodilution, and transfusion in the setting of brain-injury and stroke. The second portion is a systematic review to identify studies assessing the association between anemia or the use of red blood cell transfusions and relevant clinical outcomes in various neurocritical care populations.

RESULTS

There have been no randomized controlled trials that have adequately assessed optimal transfusion thresholds specifically among brain-injured patients. The importance of ischemia and the implications of anemia are not necessarily the same for all neurocritical care conditions. Nevertheless, there exists an extensive body of experimental work, as well as human observational and physiologic studies, which have advanced knowledge in this area and provide some guidance to clinicians. Lower hemoglobin concentrations are consistently associated with worse physiologic parameters and clinical outcomes; however, this relationship may not be altered by more aggressive use of red blood cell transfusions.

CONCLUSIONS

Although hemoglobin concentrations as low as 7 g/dl are well tolerated in most critical care patients, such a severe degree of anemia could be harmful in brain-injured patients. Randomized controlled trials of different transfusion thresholds, specifically in neurocritical care settings, are required. The impact of the duration of blood storage on the neurologic implications of transfusion also requires further investigation.

The influence of anemia on clinical presentation and outcome of patients with first-ever atherosclerosis-related ischemic stroke

There is considerable debate regarding whether anemia qualifies as a prognostic factor for stroke. The purpose of this study was twofold: first, to assess the influence of anemia on vascular risk factors and clinical presentations in patients with first-ever atherosclerosis-related ischemic stroke and, second, to evaluate whether anemia may be of prognostic importance. A total of 774 consecutive patients with first-ever atherosclerosis-related ischemic stroke were prospectively investigated. Vascular risk factors, clinical presentations and outcomes were recorded and compared between those patients with and without anemia. Stroke recurrence and mortality were recorded at the 3-year follow-up. Of the study population, 168 (21.7%) were anemic. Multivariate analysis revealed that patients with anemia were more likely to be older than 70 years (p<0.001) and have chronic renal insufficiency (p<0.001). After a mean follow-up period of 958 days, 21 (12.5%) and 24 (4.0%) of the patients in the anemic and control groups, respectively, died. Within 3 years of initial onset, the mortality rate was significantly higher in patients with anemia (p=0.021). The Kaplan-Meier analysis for patients with and without anemia showed different survival curves (Log-rank test p<0.001). Within 3 years of the onset of first-ever atherosclerosis-related ischemic stroke, patients who had anemia at the time of the initial admission had an associated higher mortality rate. The stroke risk factors of being older than 70 years and having chronic renal insufficiency were more frequently observed in those patients with anemia.

Plasma brain natriuretic peptide can be a biological marker to distinguish cardioembolic stroke from other stroke types in acute ischemic stroke

BACKGROUND

Plasma brain natriuretic peptide (BNP) is used as a marker of congestive heart failure. Moreover, plasma BNP levels are increased in patients with acute ischemic stroke, in particular, cardioembolic stroke. We investigated whether the plasma BNP level can also be used as a biological marker to differentiate specific stroke subtype, in particular cardioembolic stroke from the other ischemic stroke subtypes.

METHODS

Consecutive patients (total 200; 124 males, 76 females; mean age, 71.4 years) with acute ischemic stroke within 24 hours of onset were prospectively enrolled. We measured plasma BNP on admission. Patients were divided into four groups according to the TOAST classification: large-vessel disease (LVD), cardioembolism (CE), small-vessel disease (SVD), and other stroke. Correlation between plasma BNP level and stroke subtype was then examined.

RESULTS

Cardioembolism (41%) was the most frequent stroke subtype, followed by other stroke (34%), SVD (16%), and LVD (9%). Age, female, atrial fibrillation, NIHSS score > or = 7 on admission and mRS score > or = 3 at discharge were significantly higher in CE than in the other stroke subtypes. The mean plasma BNP level of the CE group was significantly higher than that of the other 3 subtypes (409.6 pg/mL for CE, 94.0 pg/mL for LVD, 37.4 pg/mL for SVD, and 156.9 pg/mL for others, p<0.001). The optimal cut-off concentration, sensitivity, and specificity of plasma BNP levels to distinguish CE from other stroke subtypes were 140.0 pg/mL, 80.5% and 80.5%, respectively.

CONCLUSION

Plasma BNP level is significantly higher in CE patients than in other stroke subtypes, and thus physicians should strongly consider CE when the plasma BNP level is over 140.0 pg/mL in patients with acute ischemic stroke.

Anemia and cerebral outcomes: many questions, fewer answers

A number of clinical studies have associated acute anemia with cerebral injury in perioperative patients. Evidence of such injury has been observed near the currently accepted transfusion threshold (hemoglobin [Hb] concentration, 7-8 g/dL), and well above the threshold for cerebral tissue hypoxia (Hb 3-4 g/dL). However, hypoxic and nonhypoxic mechanisms of anemia-induced cerebral injury have not been clearly elucidated. In addition, protective mechanisms which may minimize cerebral injury during acute anemia have not been well defined. Vasodilatory mechanisms, including nitric oxide (NO), may help to maintain cerebral oxygen delivery during anemia as all three NO synthase (NOS) isoforms (neuronal, endothelial, and inducible NOS) have been shown to be up-regulated in different experimental models of acute hemodilutional anemia. Recent experimental evidence has also demonstrated an increase in an important transcription factor, hypoxia inducible factor (HIF)-1alpha, in the cerebral cortex of anemic rodents at clinically relevant Hb concentrations (Hb 6-7 g/dL). This suggests that cerebral oxygen homeostasis may be in jeopardy during acute anemia. Under hypoxic conditions, cytoplasmic HIF-1alpha degradation is inhibited, thereby allowing it to accumulate, dimerize, and translocate into the nucleus to promote transcription of a number of hypoxic molecules. Many of these molecules, including erythropoietin, vascular endothelial growth factor, and inducible NOS have also been shown to be up-regulated in the anemic brain. In addition, HIF-1alpha transcription can be increased by nonhypoxic mediators including cytokines and vascular hormones. Furthermore, NOS-derived NO may also stabilize HIF-1alpha in the absence of tissue hypoxia. Thus, during anemia, HIF-1alpha has the potential to regulate cerebral cellular responses under both hypoxic and normoxic conditions. Experimental studies have demonstrated that HIF-1alpha may have either neuroprotective or neurotoxic capacity depending on the cell type in which it is up-regulated. In the current review, we characterize these cellular processes to promote a clearer understanding of anemia-induced cerebral injury and protection. Potential mechanisms of anemia-induced injury include cerebral emboli, tissue hypoxia, inflammation, reactive oxygen species generation, and excitotoxicity. Potential mechanisms of cerebral protection include NOS/NO-dependent optimization of cerebral oxygen delivery and cytoprotective mechanisms including HIF-1alpha, erythropoietin, and vascular endothelial growth factor. The overall balance of these activated cellular mechanisms may dictate whether or not their up-regulation leads to cytoprotection or cellular injury during anemia. A clearer understanding of these mechanisms may help us target therapies that will minimize anemia-induced cerebral injury in perioperative patients.

Change in N-terminal-pro-B-type-natriuretic-peptide and the risk of sudden death, stroke, myocardial infarction, and all-cause mortality in diabetic dialysis patients

Aims

N-terminal-pro-B-type-natriuretic-peptide (NT-pro-BNP) concentrations are altered in renal failure. This study examined the effect of baseline and change from baseline NT-pro-BNP on cardiovascular outcome and mortality in haemodialysis patients.

Methods and results

On the basis of the German Diabetes and Dialysis Study, which evaluated atorvastatin in 1255 type 2 diabetes mellitus (T2DM) haemodialysis patients (median follow-up 4 years), the impact of NT-pro-BNP on pre-specified, adjudicated endpoints was investigated: sudden death (SD; n = 160), stroke (n = 99), myocardial infarction (MI; n = 200), cardiovascular events (CVEs: cardiac death, MI, stroke; n = 465), all-cause mortality (n = 612). Patients with baseline NT-pro-BNP ≥9252 pg/mL (fourth quartile) exhibited a more than four-fold risk of stroke [hazard ratio (HR) 4.1; 95% confidence interval (CI) 2.0–8.4] and a more than two-fold risk of SD (HR 2.0; 95% CI 1.2–3.3), CVE (HR 2.0; 95% CI 1.5–2.7), and mortality (HR 2.1; 95% CI 1.6–2.7) compared with patients with baseline NT-pro-BNP ≤ 1433 pg/mL (first quartile). Change in NT-pro-BNP was strongly associated with SD, CVE, and mortality. Doubling of NT-pro-BNP increased the risk of death by 46% (95% CI 1.1–2.0). Neither baseline nor change in NT-pro-BNP was significantly associated with MI.

Conclusion

Increasing NT-pro-BNP is a risk factor for SD, CVE, and mortality in haemodialysis patients with T2DM. Whether NT-pro-BNP-guided treatment improves outcome needs to be evaluated prospectively.

The differential diagnosis of an elevated amino-terminal pro-B-type natriuretic peptide level

Although amino-terminal pro-B-type natriuretic peptides (NT-proBNP) are useful for the diagnosis or exclusion of heart failure (HF), this marker may identify a wide range of disease processes other than HF. Indeed, elevation of NT-proBNP may occur in a number of heart diseases (including heart muscle disease, valve disease, rhythm abnormalities, pulmonary hypertension, and cytotoxic injury to the heart) and in disease processes other than primary cardiac illnesses, including gram-negative sepsis. Importantly, although NT-proBNP may increase in settings other than HF, the presence and severity of such NT-proBNP release is often significantly associated with risk for adverse outcome. Accordingly, elevation of NT-proBNP in the context of non-HF situations should not be regarded as a "false-positive" finding, and elevated NT-proBNP values should not be discarded without consideration of the serious adverse outcomes associated with the elevation. Future studies will be necessary to further understand the utility of NT-proBNP testing in states other than cardiovascular disease.

Impact of Hemoglobin on Plasma Pro-B-Type Natriuretic Peptide Concentrations in the General Population

Background: Age, sex, and renal function contribute to variations in plasma concentrations of B-type natriuretic peptide (BNP) and its molecular precursor (proBNP). Recent studies indicate that anemia may also affect proBNP concentrations in patients with heart failure or stroke. However, the impact of hemoglobin status on proBNP concentrations has not been established in the general population.

Methods: In the 4th examination in the Copenhagen City Heart Study, we performed a nested case-control study of 6238 individuals from a Danish general population. Of these, 3497 randomly selected participants also underwent an echocardiographic examination. The population was stratified into groups depending on health and hemoglobin status. Correlations between hemoglobin and proBNP concentrations were examined by simple and multiple regression analyses, adjusted for variables known to influence the proBNP plasma concentration.

Results: The mean proBNP concentration was increased 1.7-fold in the group with anemia vs the nonanemic group [mean (SD) 42 (45) pmol/L vs 25 (29) pmol/L, P &lt;0.0001, n = 5892]. Multiple regression analysis confirmed an independent effect of hemoglobin on proBNP concentrations. In a selected subgroup without signs or symptoms of heart disease (n = 2855), lower hemoglobin concentrations, defined as &lt;120 g/L in women and &lt;130 g/L in men, were associated with increased circulating proBNP concentrations, but the contribution to the overall variation in proBNP concentrations was modest.

Conclusions: Because moderate anemia is associated with a 1.7-fold increase in proBNP concentrations, hemoglobin concentrations should be taken into consideration in patients with nonspecific symptoms of heart disease and increased proBNP concentrations.

Higher prevalence of anemia among pregnant immigrant women compared to pregnant ethnic Danish women

The aim of the study was to investigate whether the well-known high anemia prevalence in pregnant women from the eastern Mediterranean and Asian regions decreased when the women immigrated to a low-frequency region (Denmark). During 70 months, 1,741 pregnant immigrant women referred from primary care to an obligatory hemoglobinopathy screening were eligible for the study, as their screening was negative. To compare this group with a cohort of 205 pregnant ethnic Danish women, the groups were matched by gestational age, and a total of 406 immigrant women were included. Hemoglobin (Hb) and iron status parameters were examined in the two groups. The prevalence of anemia was higher in the immigrant group (20.0%) compared to the Danish women (4.9%) (P < 0.0001). Blood Hb concentration was 119 +/- 12 g/l (mean +/- SD) in the immigrant group compared to 122 +/- 9 g/l in the Danish group (P = 0.01). Erythrocyte mean corpuscular volume (MCV) was also lower in the immigrant group (87 +/- 7 fl vs 96 +/- 4 fl) (P < 0.0001). A total of 13.1% of the immigrant women had an MCV <80 fl (the lower reference limit) compared to 0.0% in the Danish group, and plasma iron, ferritin, and transferrin saturation values indicated iron deficiency. Conclusively, the pregnant immigrant women had significantly higher prevalence of anemia compared to pregnant women of Danish origin. It indicates the need for an alternative routine screening procedure for this population group, which should also include nutritional counselling.