Impact of anemia on acute ischemic stroke outcomes: A systematic review of the literature

A retrospective study on sex disparities and risk factors in acute ischemic stroke in the West bank of Palestine

Acute ischemic stroke (AIS) is one of the leading causes of mortality and morbidity. This study aimed to identify risk factors, subtypes, and associated outcomes of AIS in the West Bank based on sex. We retrospectively analyzed medical records from 2018 to 2022 of stroke patients from four main hospitals in the West Bank (N = 711). The Modified Rankin Scale (mRS) assessed post-stroke disability on presentation day and thirty days later based on patient history and physical examination findings. An adjusted multinomial logistic regression model was implemented to calculate the adjusted odds ratios (OR) and the 95% confidence interval (CI). The significance level was set at P < 0.05. Out of 711 records, 118 were excluded. The final analysis included 593 AIS patients, with a median age of 63 and an interquartile range of 15. The majority of the patients (60.37%) were males and most of them (62.1%) were smokers. Males were less likely to have diabetes mellitus (DM) (P = 0.037, OR = 0.691) and atrial fibrillation (P = 0.039, OR = 0.627) compared to females. Small-volume strokes accounted for the majority of cases (60.7%). AIS had a thrombotic cause in (81.9%) of patients. On presentation, (40.4%) and (37.2%) of patients had more severe symptoms with mRS scores of 4 and 3, respectively. Males were more likely than females (P = 0.018, OR = 2.03) to present with more severe symptoms (mRS 3-4-5) on day one. An increase of one year in age resulted in a 9.8% higher risk of death (mRS 6) on day one (P = 0.016, OR = 1.098). Smoking history was associated with a seven-fold increase in mortality on day one (P = 0.049, OR = 7.396). Males developed AIS at a younger age while DM and atrial fibrillation were significantly more common in females. The majority of patients reported more severe symptoms on presentation, with notable differences observed between sexes. Male patients exhibited a higher prevalence of severe symptoms compared to female patients. Additionally, key risk factors such as smoking was significantly associated with the severity of symptoms at presentation, with variations observed across sexes. Prevention of risk factors (e.g., HTN, DM, atrial fibrillation, and smoking) is crucial, and further research is required.

Impact of hemoglobin levels on acute ischemic stroke severity

Introduction

Stroke is one of the most common causes of disability and mortality worldwide. In Saudi Arabia, it is a crucial health issue. Ischemic stroke is the most common type of stroke in this area, and understanding its relationship with hemoglobin (Hgb) levels is vital. To date, no study has established an exact relationship between Hgb levels and stroke severity. This study assessed the association between Hgb levels and the severity of acute ischemic stroke (AIS) at presentation.

Methods

We conducted a retrospective study of patients admitted and diagnosed with AIS between 2013 and 2017. The exclusion criteria included other stroke types (such as hemorrhagic or venous infarction), patients with a history of internal bleeding, and pregnant and lactating women. The patients were divided into three groups based on Hgb levels: low, average, and high. Correlations were analyzed between these groups and the National Institutes of Health Stroke Scale (NIHSS) scores, stroke outcomes at discharge (cured, improved, or mortality decreased), and stroke subtype, as determined and classified by the TOAST classification criteria.

Results

The Pearson correlation coefficient showed a weak positive correlation between Hgb levels and NIHSS scores. Neither stroke outcomes nor stroke types showed significant correlations with mean Hgb level.

Conclusion

The results of this retrospective study on a small cohort of patients diagnosed with AIS indicate that higher Hgb levels at hospital admission are associated with greater stroke severity, as measured by the NIHSS score. However, no significant effect was observed on stroke outcome at discharge or the TOAST classification.

Assessing anemia in stroke patients through virtual non-contrast imaging with photon-counting detector CT: validation on supra-aortic vessel CT-Angiography

BACKGROUND AND PURPOSE

Anemia is a common comorbidity in stroke patients, traditionally detected via blood tests. This study evaluates the feasibility of using virtual non-contrast (VNC) imaging from photon counting detector-CT (PCD-CT) angiography to detect anemia and identifies the optimal anatomical site for assessment.

MATERIALS AND METHODS

In this retrospective study of 80 patients undergoing PCD-CT angiography of supra-aortic vessels, VNC series were analyzed at various anatomical sites, including the jugular veins, aorta, and cerebral sinuses. Correlations between serum hemoglobin (Hb) levels and VNC Hounsfield Unit (HU) values were assessed using Pearson's coefficients. Linear regression and ROC analysis evaluated diagnostic performance.ResultsThe jugular veins showed the strongest correlation between VNC HU values and Hb levels (R2 = 0.49, p < 0.001), with weaker correlations in arterial vessels like the aorta (R2 = 0.11, p < 0.001). ROC analysis of jugular vein VNC values yielded an AUC of 0.79 for anemia detection. Correlation strength declined with longer intervals between imaging and blood tests, suggesting temporal Hb variability.

CONCLUSIONS

VNC imaging in CT angiography is a feasible method for detecting anemia, with the jugular veins providing the most reliable site for assessment. VNC imaging could be a valuable alternative when blood tests are delayed or unavailable.

Outcomes of Blood Transfusions in Patients Undergoing Mechanical Thrombectomy for Acute Ischemic Stroke: A Population-Based Cross-Sectional Study of 47,835 Patients

Background/Objectives: Despite advances, large vessel occlusion strokes (LVO) remain associated with significant morbidity. Recent studies have suggested that blood transfusions may help manage critically ill LVO patients. We sought to evaluate the patient characteristics, complications, and clinical outcomes associated with blood transfusions in acute ischemic stroke (AIS) patients undergoing endovascular thrombectomy. Methods: A query of the 2016-2019 National Inpatient Sample was conducted to identify AIS patients who underwent endovascular thrombectomy, using International Classification of Disease 10th Revision diagnostic codes. Demographic, clinical characteristics, severity of presentation, complications, and outcomes were analyzed. Multivariate binary logistic regression was used to assess complications, length of stay (LOS), discharge disposition, and inpatient mortality. Results: A total of 47,835 AIS patients undergoing endovascular thrombectomy were identified. Of these patients, 1215 (2.5%) received blood transfusions. After controlling for age, gender, National Institutes of Health Stroke Scale scores, Elixhauser Comorbidity Index, and location of stroke, blood transfusions were significant positive predictors for higher rates of inpatient death (OR: 1.96; 95% CI: 1.681, 2.286; p < 0.001), lower rates of routine discharge (OR: 0.425; 95% CI: 0.342, 0.527; p < 0.001), and prolonged LOS (OR: 2.928; 95% CI: 2.572, 3.333; p < 0.001). Conclusions: Blood transfusions in AIS patients receiving endovascular thrombectomy are associated with elevated complication rates, extended hospital stays, and increased mortality, even after for controlling for predictors of poor outcome. Understanding the broader effects of blood transfusions in AIS patients is essential to ensure that the balance between potential benefits and risks upholds best care practice for all patients.

Association between the hemoglobin-to-red cell distribution width ratio and three-month unfavorable outcome in older acute ischemic stroke patients: a prospective study

Objective

Acute ischemic stroke (AIS) is a prevalent acute condition among older individuals. This study is the first investigation of the link between the HRR and unfavorable three-month outcome in older AIS patients.

Methods

This secondary research used data from a sample of 1,470 older AIS patients collected from a South Korean hospital between January 2010 and December 2016. Multiple imputation was applied to account for absent values. Binary logistic regression analysis was used to examine the relationship between the baseline HRR and adverse outcome at three-month. Restricted cubic spline analysis was employed to evaluate the correlation between HRR levels and adverse outcome. Interaction tests were performed to discern variations among subgroups.

Results

At 3 months, the overall incidence of adverse events was 31.43%, with a median HRR of 9.49. Compared to those with a lower HRR (Q1), the adjusted odds ratios (ORs) for the HRR in Q2, Q3, and Q4 were 0.61 (95% CI: 0.41-0.92, p = 0.017), 0.49 (95% CI: 0.31-0.78, p = 0.003), and 0.54 (95% CI: 0.31-0.92, p = 0.025), respectively. The correlation between the HRR and adverse outcome was non-linear (p < 0.05). An inflection point threshold of 10.70 was established via RCS analysis. Each 1-unit increase in HRR on the left side of the infection point was associated with a 24.0% decrease in the likelihood of adverse outcomes (OR = 0.76, 95% CI: 0.66-0.86, p < 0.001). ROC analysis revealed that HRR had the highest AUC (0.64, 95% CI: 0.61-0.67), followed by hs-CRP (0.60, 95% CI: 0.57-0.63), FPG/HbA1c (0.59, 95% CI: 0.55-0.63), and WBC (0.55, 95% CI: 0.51-0.58).

Conclusion

A lower HRR was correlated with a higher risk for adverse outcome in older AIS patients.

Association between hemoglobin level and clinical outcomes in ischemic stroke patients with high-grade carotid artery stenosis

OBJECTIVE

Abnormal hemoglobin levels may influence stroke outcome, while high-grade carotid artery stenosis (CAS) is linked to distal hemodynamic compromise. The relationship between hemoglobin and ischemic stroke (IS) outcome in patients with high-grade CAS remains unclear. We aimed to investigate this association in acute IS patients with high-grade CAS.

METHODS

To compare the characteristics and outcome in acute IS patients with high-grade CAS across different hemoglobin levels, we conducted an observational cohort study from January 2007 to April 2012 and followed for 5 years.

RESULTS

Among 372 enrolled patients, 75 had hemoglobin < 12 g/dL, 153 had 12-14 g/dL, and 144 had > 14 g/dL. Hemoglobin < 12 g/dL was associated with higher rates of congestive heart failure, gout, and chronic kidney disease, but lower rate of hyperlipidemia. Hemoglobin< 12 g/dL had lower levels of white blood cells, total cholesterol, and estimated glomerular filtration rate, but higher levels of high-sensitivity C-reactive protein and potassium. The Cox proportional hazards model revealed that hemoglobin< 12 g/dL was associated with higher risk of all-cause mortality (hazard ratio (HR) 1.99, 95 % confidence interval (CI) 1.20-3.32, P = 0.008) and lower risk of stroke recurrence over 5 years in IS patients with high-grade CAS (HR 0.50, 95 % CI 0.26-0.95; P = 0.033).

CONCLUSIONS

Hemoglobin< 12 g/dL was associated with higher mortality and lower stroke recurrence risk over 5 years in IS patients with high-grade CAS. Further studies are warranted to determine the optimal hemoglobin level for improving outcomes in these patients.

The Hematological and Social Factors Affecting Length of Stay in Acute Stroke Patients: A Quality Assessment Study From a Single Institute

INTRODUCTION

Stroke is one of the common causes of mortality. The length of stay (LOS) for a stroke is a quality indicator and affects mortality. However, there are no large studies evaluating the LOS in an acute inpatient setting for stroke patients, mainly hematological and social parameters. In this quality assessment observational study, we analyzed the LOS in acute stroke patients at our institute.

METHODS

We measured the LOS and divided the study population into two arms, arm A and arm B, to include patients with LOS≤10 and >10 days, respectively. We analyzed various factors affecting LOS and compared the two study arms and the literature.

RESULTS

There were 483 patients with acute stroke in our study. The median LOS was 7.2±6.4 days (range 0.1 to 49.7). Patient age (p<0.00001), female gender (p<0.00001), hemorrhagic stroke (p=0.03), independence with ambulation before stroke (p<0.00001), type of placement (p<0.00001), type of insurance (p=0.0002), obesity (p 0.01) and anemia (p<0.00001), affected the LOS in our study. Most patients in arm B had medical complications (66%) during hospitalization.

CONCLUSIONS

In our quality assessment study, we observed that certain factors were associated with longer lengths of stay (LOS) among patients. These included geriatric age, female gender, hemorrhagic stroke, lack of ambulation independence, specific social determinants, discharge disposition to a facility, Medicare/Medicaid insurance, non-obesity, and hematological parameters such as anemia. The majority of these patients had additional medical complications. Thrombocytosis has been linked to reduced mortality in hemorrhagic stroke in the literature. However, our study found that platelet count does not significantly impact the length of stay (LOS) in ischemic stroke patients.

Association of iron deficiency anaemia with the hospitalization and mortality rate of patients with COVID‑19

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) illness led to the coronavirus disease 2019 (COVID-19) pandemic, which has caused enormous health and financial losses, as well as challenges to global health. Iron deficiency anaemia (IDA) has been linked to adverse outcomes in patients infected with SARS-COV-2. The present study aimed to assess the association between IDA and the severity of COVID-19 in hospitalized patients. For this purpose, a retrospective data analysis of 100 patients with COVID-19 was conducted. Data of patients hospitalized with SARS-COV-2 infection confirmed by RT-PCR were collected between June, 2021 and March, 2022. The collected data included patient demographics, comorbidities, clinical signs, symptoms and IDA medical laboratory findings, including complete blood count and iron profiles. The results revealed that patients with COVID-19 admitted to the isolation unit represented 61.0% of the study sample, whereas 39.0% were admitted to the intensive care unit (ICU). No patients had stage I IDA, whereas 4 patients (4%) had stage II IDA. Furthermore, 19 patients (19.0%) had stage III IDA. A significantly higher proportion of patients with IDA (69.6%) were admitted to the ICU compared with those without IDA (29.9%, P<0.001). Additionally, patients with IDA had a higher proportion of a history of stroke compared with those without IDA (17.4 vs. 2.6%, respectively, P=0.024). The most common comorbidities identified were hypertension (29%), diabetes (23%) and heart problems (17%). On the whole, the present study demonstrates significant associations between IDA and a longer hospitalization period. A greater incidence of complications was observed in the hospitalized patients who were SARS-COV-2-positive. Although further studies with larger sample sizes are required to confirm these findings, the results presented herein may provide insight for physicians as regards the prevention and treatment of patients with IDA who are infected with coronavirus.

Anemia and Optimal Transfusion Thresholds in Brain-Injured Patients: A Narrative Review of the Literature

Anemia is a highly prevalent condition that may compromise oxygen delivery to vital organs, especially among the critically ill. Although current evidence supports the adoption of a restrictive transfusion strategy and threshold among the nonbleeding critically ill patient, it remains unclear whether this practice should apply to the brain-injured patient, given the predisposition to cerebral ischemia in this patient population, in which even nonprofound anemia may exert a detrimental effect on clinical outcomes. The purpose of this review is to provide an overview of the pathophysiological changes related to impaired cerebral oxygenation in the brain-injured patient and to present the available evidence on the effect of anemia and varying transfusion thresholds on the clinical outcomes of patients with acute brain injury.

Beyond diagnosis: Leveraging routine blood and urine biomarkers to predict severity and functional outcome in acute ischemic stroke

Background

The initial severity of acute ischemic stroke (AIS) is a crucial predictor of the disease outcome. In this study, blood and urine biomarkers from patients with AIS were measured to estimate stroke severity and predict long-term stroke outcomes.

Methods

The medical records of patients with AIS between October 2016 and May 2020 were retrospectively analyzed. The relationships of blood and urine biomarkers with stroke severity at admission were evaluated in patients with AIS. Predictive models for initial stroke severity and long-term prognosis were then developed using a panel of identified biomarkers.

Results

A total of 2229 patients were enrolled. Univariate analysis revealed 12 biomarkers associated with the National Institutes of Health Stroke Scale scores at admission. The area under the curve values for predicting initial stroke severity and long-term prognosis on the basis of these biomarkers were 0.7465, 0.7470, and 0.8061, respectively. Among multiple tested machine-learning, eXtreme gradient boosting exhibited the highest effectiveness in predicting 90-day modified Rankin Scale scores. SHapley Additive exPlanations revealed fasting glucose, albumin, hemoglobin, prothrombin time, and urine-specific gravity to be the top five most crucial biomarkers.

Conclusion

These findings demonstrate that clinically available blood and urine biomarkers can effectively estimate initial stroke severity and predict long-term prognosis in patients with AIS. Our results provide a scientific basis for developing tailored clinical treatment and management strategies for AIS, through incorporating liquid biomarkers into stroke risk assessment and patient care protocols for patients with AIS.

Association Between Anemia and Clinical Outcome in Acute Ischemic Stroke Patients Treated With Endovascular Treatment

BACKGROUND AND PURPOSE

Endovascular treatment (EVT) is the preferred treatment option in eligible acute ischemic stroke (AIS) patients with a large vessel occlusion of the anterior circulation. Several comorbidities have been identified that can affect clinical outcomes. Various studies have investigated the association between anemia and clinical outcome and found conflicting.

RESULTS

. The aim is to investigate the association between pre-EVT anemia and clinical outcomes at different time points post-EVT, primarily focusing on the National Institutes of Health Stroke Scale (NIHSS) at 24-48 hours.

METHODS

We prospectively included 560 AIS patients who received EVT in the Maastricht University Medical Center+. Hemoglobin levels (Hb; g/dL) were determined on admission. Hb levels were also categorized into two groups: anemia (male: Hb ≤12.9 g/dL; female: Hb ≤11.9 g/dL) and no anemia. Multiple imputation was used to handle missing data. Multivariable regression was used to investigate the association between anemia or Hb levels and clinical outcomes.

RESULTS

Anemia was present in 26% of the patients. Multivariable regression did not show a significant association between anemia or Hb levels and NIHSS at 24-48 hours (adjusted β [aβ]anemia: 1.44, 95% confidence interval [CI]: -0.47 to 3.36; aβHb: -0.37, 95% CI: -0.88 to 0.13). However, multivariable regression showed significant associations with modified Rankin Scale (adjusted common odds ratio [acOR]anemia: 1.66, 95% CI: 1.12 to 2.48; acORHb: 0.83, 95% CI: 0.75 to 0.93) and poor functional outcome at 90 days (adjusted OR [aOR]anemia: 2.09, 95% CI: 1.21 to 3.63; aORHb: 0.80, 95% CI: 0.69 to 0.92).

CONCLUSION

Anemia was not independently associated with early neurological deficit (NIHSS) post-AIS, suggesting it is more suitable as a general frailty marker.