Red cell distribution width is associated with future risk of incident stroke. The Tromsø Study

Is Red Cell Distribution Width a Reliable Marker for Cardiovascular Diseases? A Narrative Review

Red cell distribution width (RDW) is an easy-to-access marker which is routinely measured in complete blood count (CBC) test. Besides the classic use of RDW as a marker for discriminating different types of anemia, recent studies had indicated the relationship between high RDW and cardiovascular diseases. High RDW is not only useful in the diagnosis and prognostication of various cardiovascular conditions but also could be used as a valuable tool for predicting the incidence of cardiovascular diseases. population-based studies have indicated that higher RDW could effectively predict the incidence of heart failure (HF), atherosclerotic diseases, and atrial fibrillation (AF). It has been also demonstrated that higher RDW is associated with worse outcomes in these diseases. Recent studies have shown that high RDW is also associated with other cardiovascular conditions including cardiomyopathies, and pulmonary hypertension. The predictive role of RDW in endovascular interventions has also been demonstrated by many recent studies. Here in this review, we attempt to compile the most recent findings with older reports regarding the relation between high RDW and HF, cardiomyopathies, pulmonary hypertension, AF, atherosclerotic disorders, primary hypertension, and the outcomes of endovascular interventions. we also discussed the role of RDW in the prognostication of different cardiovascular conditions when combined with classic classification criteria.

Red cell distribution width to total serum calcium ratio and in-hospital mortality risk in patients with acute ischemic stroke: A MIMIC-IV retrospective analysis

We investigated the relationship among red cell distribution width (RDW), to total serum calcium (TSC) ratio (RCR), and in-hospital mortality in patients with acute ischemic stroke (AIS). This study was a retrospective analysis. The data of 2700 AIS patients was retrospectively analyzed from the Medical Information Mart for Intensive Care database (version IV). The main outcome of interest was in-hospital mortality. A Cox proportional hazards regression model was used to determine whether RCR was independently associated with in-hospital mortality. The Kaplan-Meier method was used to plot the survival curves for RCR. Subgroup analyses were performed to measure the mortality across various subgroups. The area under curve (AUC) of receiver operating characteristic curve (ROC) was calculated to ascertain the quality of RCR as a predictor of in-hospital mortality in patients with AIS. In the multivariate analysis, statistically significant differences were identified in age, ethnicity, length of ICU stay, mechanical ventilation, sequential organ failure assessment (SOFA) score, RDW, hemoglobin, RCR, whether taking anticoagulants, hyperlipidemia, and atrial fibrillation (P < .05). A threshold inflection point value of 1.83 was obtained through a two-piecewise regression model. There was a non-linear relationship between RCR and hospital mortality in patients with AIS. The hazard ratio (HR) and the 95% confidence intervals (CI) on the right and left of the inflection point were 0.93 (0.57-1.51; P = .7660) and 2.96 (1.37-6.42; P = .0060), respectively. The Kaplan-Meier curve indicated that survival rates were higher when RCR was ≤ 1.83 and lower when RDW was > 1.83 after adjustment for age, gender, BMI, ethnicity. The area under curve (AUC) of RCR was 0.715. A higher RCR was associated with an increased risk of in-hospital mortality in patients with AIS.

Red cell distribution width and its polygenic score in relation to mortality and cardiometabolic outcomes

Introduction

Elevated red cell distribution width (RDW) has been associated with a range of health outcomes. This study aims to examine prognostic and etiological roles of RDW levels, both phenotypic and genetic predisposition, in predicting cardiovascular outcomes, diabetes, chronic kidney disease (CKD) and mortality.

Methods

We studied 27,141 middle-aged adults from the Malmö Diet and Cancer study (MDCS) with a mean follow up of 21 years. RDW was measured with a hematology analyzer on whole blood samples. Polygenic scores for RDW (PGS-RDW) were constructed for each participant using genetic data in MDCS and published summary statistics from genome-wide association study of RDW (n = 408,112). Cox proportional hazards regression was used to assess associations between RDW, PGS-RDW and cardiovascular outcomes, diabetes, CKD and mortality, respectively.

Results

PGS-RDW was significantly associated with RDW (Pearson's correlation coefficient = 0.133, p < 0.001). RDW was significantly associated with incidence of stroke (hazard ratio (HR) per 1 standard deviation = 1.06, 95% confidence interval (CI): 1.02-1.10, p = 0.003), atrial fibrillation (HR = 1.09, 95% CI: 1.06-1.12, p < 0.001), heart failure (HR = 1.13, 95% CI: 1.08-1.19, p < 0.001), venous thromboembolism (HR = 1.21, 95% CI: 1.15-1.28, p < 0.001), diabetes (HR = 0.87, 95% CI: 0.84-0.90, p < 0.001), CKD (HR = 1.08, 95% CI: 1.03-1.13, p = 0.004) and all-cause mortality (HR = 1.18, 95% CI: 1.16-1.20, p < 0.001). However, PGS-RDW was significantly associated with incidence of diabetes (HR = 0.96, 95% CI: 0.94-0.99, p = 0.01), but not with any other tested outcomes.

Discussion

RDW is associated with mortality and incidence of cardiovascular diseases, but a significant association between genetically determined RDW and incident cardiovascular diseases were not observed. However, both RDW and PGS-RDW were inversely associated with incidence of diabetes, suggesting a putative causal relationship. The relationship with incidence of diabetes needs to be further studied.

Association between red cell distribution width-to-platelet ratio and short-term and long-term mortality risk in patients with acute ischemic stroke

BACKGROUND

The objective of this study was to evaluate the association between red cell distribution width/platelet ratio (RPR) and 30-day and 1-year mortality in acute ischemic stroke (AIS).

METHODS

Data for the retrospective cohort study were collected from the Medical Information Mart for Intensive Care (MIMIC) III database. RPR was divided into two groups: RPR ≤ 0.11 and RPR > 0.11. The study outcomes were 30-day mortality and 1-year mortality from AIS. Cox proportional hazard models were utilized to assess the association between RPR and mortality. Subgroup analyses were applied based on age, tissue-type plasminogen activator (IV-tPA), endovascular treatment, and myocardial infarction.

RESULTS

A total of 1,358 patients were included in the study. Short- and long-term mortality occurred in 375 (27.61%) and 560 (41.24%) AIS patients, respectively. A high RPR was significantly associated with increased 30-day [hazard ratio (HR): 1.45, 95% confidence interval (CI): 1.10 to 1.92, P = 0.009] and 1-year mortality (HR: 1.54, 95%CI: 1.23 to 1.93, P < 0.001) in AIS patients. Meanwhile, RPR was found to be significantly related to 30-day mortality in AIS patients aged < 65 years (HR: 2.19, 95% CI: 1.17 to 4.10, P = 0.014), without IV-tPA use (HR: 1.42, 95% CI: 1.05 to 1.90, P = 0.021), without using endovascular treatment (HR: 1.45, 95% CI: 1.08 to 1.94, P = 0.012), and without myocardial infarction (HR: 1.54, 95% CI: 1.13 to 2.10, P = 0.006). Additionally, RPR was associated with 1-year mortality in AIS patients aged < 65 years (HR: 2.54, 95% CI: 1.56 to 4.14, P < 0.001), aged ≥ 65 years (HR: 1.38, 95% CI: 1.06 to 1.19, P = 0.015), with (HR: 1.46, 95% CI: 1.15 to 1.85, P = 0.002) and without using IV-tPA (HR: 2.30, 95% CI: 1.03 to 5.11, P = 0.041), without using endovascular treatment (HR: 1.56, 95% CI: 1.23 to 1.96, P < 0.001), and without myocardial infarction (HR: 1.68, 95% CI: 1.31 to 2.15, P < 0.001).

CONCLUSION

Elevated RPR is associated with a high risk of short-term and long-term mortality in AIS.

Association between red blood cell distribution width and ischemic stroke recurrence in patients with acute ischemic stroke: a 10-years retrospective cohort analysis

Numerous studies have reported that a higher red blood cell distribution width (RDW) level was associated with adverse outcomes in patients with the first stroke. However, no studies have examined the association between RDW and recurrent ischemic stroke. We performed a population-based cohort data analysis from 2007 to 2017. Baseline RDW was measured in 6402 first ischemic stroke participants, who were followed for about five years on average. During 62 months of median follow-up, 205 participants (3.20%) reported a recurrence (self-reported). RDW showed a nonlinear relationship with the risk of ischemic stroke recurrence. When RDW was assessed as quartiles (quartile 1, RDW<12.4; quartile 2, 12.4 to 12.8; quartile 3,12.8 to 13.3, quartile4, RDW>13.3), compared with the reference group (quartile 1), the hazard ratios (HRs) of ischemic stroke recurrence were 1.372 (95% confidence interval [CI]=0.671-2.805, P=0.386) in quartile 2, 1.835 (95% CI=1.222-2.755, P=0.003) in quartile 3, and 1.732 (95% CI=1.114-2.561, P<0.001) in quartile 4. The trend test was significant (P<0.001). When quartiles 3 and 4 were combined, the adjusted HR of ischemic stroke recurrence was 1.439 (95% CI=1.330-1.556, P<0.001) compared with the combined quartiles 1 and 2 subgroups. This study demonstrated that elevated RDW levels were positively associated with an increased risk of recurrent ischemic stroke. RDW can provide a new perspective for initial risk assessment and identify high-risk patients early. Further research is required to confirm our results.

Red cell distribution width: a novel predictive biomarker for stroke risk after transient ischaemic attack

OBJECTIVE

Predicting the prognosis of transient ischaemic attack (TIA) is difficult for many frontline clinicians. The purpose of this study was to determine whether subsequent stroke in TIA patients can be predicted via red blood cell distribution width (RDW).

MATERIAL AND METHODS

A total of 360 consecutive patients with new-onset TIA in our stroke centre, were enrolled over the period studied. The patients were divided into three groups: 103 TIA patients, 206 ischaemic stroke (IS) patients and 51 patients with haemorrhagic stroke (HS) within 7 days after TIA. Complete blood count, biochemical parameters and brain imaging were performed on all patients.

RESULTS

The mean RDW values of patients with IS and HS after TIA were significantly higher than patients with TIA (13.35 ± 1.59 vs 12.84 ± 1.19, 13.32 ± 1.08 vs 12.84 ± 1.19, respectively, all p ≤ .001). In a multivariate model, RDW was independently associated with stroke after TIA (IS: odds ratio (OR) = 2.52, 95% confidence interval (CI) = 1.46-3.35, p = .002; HS: OR = 1.511, 95% CI = 1.101-2.074, p = .011). Compared to ABCD² scores, the diagnostic power of RDW in the differentiation of patients with IS after TIA was better (area under curve (AUC): 0.731 vs 0.613, p = .015). When an RDW cut-off value of 13.95% was accepted for differentiating patients with IS from TIA, the sensitivity and specificity were 73.7% and 74.3%, respectively. However, the AUC for the ability of the RDW to predict HS was 0.653 (95% CI = 0.589-0.716; p < .001).

CONCLUSIONS

The early determination of RDW is a promising, rapid, easy and inexpensive biomarker to predict the subsequent stroke in TIA patients, especially for IS. KEY MESSAGESThe most important result of our study is to show that (1) the higher RDW, the earlier the stroke onset and (2) RDW ≥13.95% has a 2.52-fold risk of ischaemic stroke in TIA patients, and RDW ≥12.85% has a 1.51-fold risk of haemorrhagic stroke.As an economic and accessible hematological marker, baseline RDW may serve as a useful biomarker for risk stratification in TIA patients.

Nomogram for Predicting Postoperative Portal Venous Systemic Thrombosis in Patients with Cirrhosis Undergoing Splenectomy and Esophagogastric Devascularization

OBJECTIVES

The aim of the study is to develop a nomogram for predicting postoperative portal venous systemic thrombosis (PVST) in patients with cirrhosis undergoing splenectomy and esophagogastric devascularization.

METHODS

In total, 195 eligible patients were included. Demographic characteristics were collected, and the results of perioperative routine laboratory investigations and ultrasound examinations were also recorded. Blood cell morphological traits, including the red cell volume distribution width (RDW), mean platelet volume, and platelet distribution width, were identified. Univariate and multivariate logistic regressions were implemented for risk factor filtration, and an integrated nomogram was generated and then validated using the bootstrap method.

RESULTS

A color Doppler abdominal ultrasound examination on a postoperative day (POD) 7 (38.97%) revealed that 76 patients had PVST. The results of the multivariate logistic regression suggested that a higher RDW on POD3 (RDW3) (odds ratio (OR): 1.188, 95% confidence interval (CI): 1.073-1.326), wider portal vein diameter (OR: 1.387, 95% CI: 1.203-1.642), history of variceal hemorrhage (OR: 3.407, 95% CI: 1.670-7.220), and longer spleen length (OR: 1.015, 95% CI: 1.001-1.029) were independent risk parameters for postoperative PVST. Moreover, the nomogram integrating these four parameters exhibited considerable capability in PVST forecasting. The nomogram's receiver operating characteristic curve reached 0.83 and achieved a sensitivity and specificity of 0.711 and 0.848, respectively, at its cutoff. The nomogram's calibration curve demonstrated that it was well calibrated.

CONCLUSION

The nomogram exhibited excellent performance in PVST prediction and might assist surgeons in identifying vulnerable patients and administering timely prophylaxis.

Red blood cell distribution width in different time-points of peripheral thrombolysis period in acute ischemic stroke is associated with prognosis

The relationship between red blood cell distribution width (RDW) in peripheral thrombolysis period and prognosis is not fully clarified in those who underwent intravenous thrombolysis (IVT) for acute ischemic stroke (AIS). Our study aimed to clarify this issue. A retrospective analysis of about 510 consecutive thrombolysis cases for AIS from January 2015 to March 2019 in a single-center database was done and followed-up for 3 months. We used univariate and multivariable models to evaluate the relationship between RDW levels at various time-points after IVT and the occurrence risk of hemorrhagic transformation (HT) and recurrent stroke, and used COX regression to assess the hazard ratios of outcomes with RDW levels. Elevated risk of HT was found in higher tertiles of RDW (OR = 10.282, 95% confidence interval (CI) 2.841–39.209, P < 0.001 in Tp tertile G3; OR = 5.650, 95% CI 1.992–16.025, P = 0.001 in T24 tertile G3; OR = 4.308, 95% CI 1.480–12.542, P = 0.007 in T48 tertile G3 and OR = 6.384, 95% CI 2.201–18.515, P = 0.001 in T72 tertile G3, respectively). Occurrence of recurrent stroke was highest in the RDW tertile G3 (HR = 4.580, 95% CI 2.123–9.883, P < 0.001 in Tp tertile G3; HR = 5.731, 95% CI 2.498–13.151, P = 0.001 in T24 tertile G3; HR = 3.019, 95% CI 1.969–4.059, P = 0.031 in T48 tertile G3; HR = 3.318, 95% CI 1.598–6.890, P = 0.001 in T72 tertile G3, respectively). Mean RDW levels ≥13.60 among AIS patients undergoing thrombolysis was associated with higher risk of HT and recurrent stroke.

Red Blood Cell Distribution Width Is Associated With Adverse Kidney Outcomes in Patients With Chronic Kidney Disease

Background

Chronic kidney disease (CKD) is a global public health issue. Red blood cell distribution width (RDW) is a recently recognized potential inflammatory marker, which mirrors the variability in erythrocyte volume. Studies indicate that elevated RDW is associated with increased risk of mortality in CKD patients, while evidence regarding the impact of RDW on kidney outcome is limited.

Methods

Altogether 523 patients with CKD stage 1-4 from a single center were enrolled. We identified the cutoff point for RDW level using maximally selected log-rank statistics. The time-averaged estimated glomerular filtration rate (eGFR) slope was determined using linear mixed effects models. Rapid CKD progression was defined by an eGFR decline >5 ml/min/1.73 m²/year. The composite endpoints were defined as doubling of serum creatinine, a 30% decline in initial eGFR or incidence of eGFR < 15 ml/min/1.73 m², whichever occurred first. Multivariable logistic regression or Cox proportional hazards regression was performed, as appropriate.

Results

During a median follow-up of 26 [interquartile range (IQR): 12, 36] months, 65 (12.43%) patients suffered a rapid CKD progression and 172 (32.89%) composite kidney events occurred at a rate of 32.3/100 patient-years in the high RDW group, compared with 14.7/100 patient-years of the remainder. The annual eGFR change was clearly steeper in high RDW group {-3.48 [95% confidence interval (CI): -4.84, -2.12] ml/min/1.73 m²/year vs. -1.86 [95% CI: -2.27, -1.45] ml/min/1.73 m²/year among those with RDW of >14.5% and ≤14.5%, respectively, P for between-group difference <0.05}. So was the risk of rapid renal function loss (odds ratio = 6.79, 95% CI: 3.08-14.97) and composite kidney outcomes (hazards ratio = 1.51, 95% CI: 1.02-2.23). The significant association remained consistent in the sensitivity analysis.

Conclusion

Increased RDW value is independently associated with accelerated CKD deterioration. Findings of this study suggest RDW be a potential indicator for risk of CKD progression.

Acute Myocardial Infarction (AMI) as the Effect Modifiers to Modify the Association Between Red Blood Cell Distribution Width (RDW) and Mortality in Critically Ill Patients With Stroke

Background and Objectives

Few studies have evaluated the impact of red blood cell distribution width (RDW) on prognosis for critically ill patients with acute stroke according to recent studies. The aim of this study was to investigate the association between RDW and mortality in these patients.

Methods

Clinical data were extracted from the eICU Collaborative Research Database (eICU-CRD) and analyzed. The exposure of interest was RDW measured at admission. The primary outcome was in-hospital mortality. Binary logistic regression models and interaction testing were performed to examine the RDW-mortality relationship and effect modification by acute myocardial infarction and hypertension (HP).

Results

Data from 10,022 patients were analyzed. In binary logistic regression analysis, after adjusting for potential confounders, RDW was found to be independently associated with in-hospital mortality {odds ratio (OR) 1.07, [95% confidence interval (CI) 1.03 to 1.11]; p = 0.001}. Higher RDW linked to an increase in mortality (OR, 1.07; 95% CI, 1.03 to 1.11; P for trend < 0.0001). Subgroup analysis showed that, in patients combined with AMI and without HP (both P-interaction <0.05), the correlation between RDW and in-hospital mortality is stronger (AMI group: OR, 1.30; 95% CI, 1.07 to 1.58, not the AMI group: OR, 1.06; 95% CI, 1.02, 1.10; the HP group: OR,.98; 95% CI,.91 to 1.07, not the HP group: OR, 1.09; 95% CI, 1.05 to 1.14).

Conclusions

A higher baseline RDW is independently correlated with prognosis in critically ill patients with acute stroke, and the correlation can be modified by AMI and HP duration.

Early neutrophil-to-lymphocyte ratio is a prognostic marker in acute minor stroke or transient ischemic attack

Intravenous injection of alteplase is recommended for patients with minor disabling and not non-disabling ischemic stroke symptoms within 4.5 h of ischemic stroke symptom onset. However, it is hard for clinicians to distinguish which type of minor ischemic stroke is disabled at an early stage. In this study, we aimed to demonstrate early neutrophil-to-lymphocyte ratio is a prognostic marker in acute minor stroke or transient ischemic attack. 196 patients diagnosed with acute minor stroke or transient ischemic attack within 24 h of symptom onset were enrolled. Patients were divided into three groups according to the neutrophil-to-lymphocyte ratio value (< 2, 2-3, > 3). Clinical, neuroradiological, laboratory and follow-up data were collected from electronic database. Functional outcome was assessed by modified Rankin Scale. Neutrophil-to-lymphocyte ratio associated with functional outcome of 90 days was evaluated by logistic regression analysis, and we used receiver operating characteristic curve analysis to detect the overall predictive accuracy of this marker. Early neutrophil-to-lymphocyte ratio was associated with an increased risk of short-term functional outcome (OR 4.502, 95% CI 1.533-13.046, P = 0.006). The optimal cutoff value of neutrophil-to-lymphocyte ratio for prediction of short-term unfavorable outcome was 2.94 with a sensitivity of 69.6% and a specificity of 77.1% (area under the curve: 0.767, 95% CI 0.691-0.843). Early neutrophil-to-lymphocyte ratio is associated with short-term unfavorable functional outcome in patients with acute minor stroke or transient ischemic attack. Early neutrophil-to-lymphocyte ratio is beneficial for clinicians to distinguish minor disabling ischemic stroke at an early stage.

Red Cell Distribution Width: Commonly Performed Test Predicts Mortality in Primary Total Joint Arthroplasty

INTRODUCTION

Mortality after total joint arthroplasty (TJA) has been thoroughly explored. Short and long-term mortality appear to be correlated with patient comorbidities. Red Cell Distribution Width (RDW) is a commonly performed test that reflects the variation in red blood cell size. This study investigated the utility of RDW, when combined with comorbidity indices, in predicting mortality after TJA.

METHODS

Using a single institutional database, 30,437 primary TJA were identified. Patient demographics (age, gender, body mass index (BMI), pre-operative hemoglobin, RDW, and Charlson Comorbidity Index(CCI)) were queried. The primary outcome was 1-year mortality after TJA. Anemia was defined as hemoglobin <12g/dL for women and <13 g/dL for men. The normal range for RDW is 11.5-14.5%. A preliminary analysis assessed the bivariate association between demographics, preoperative anemia, RDW, CCI, and all-cause mortality within 1-year after TJA. A multivariate regression model was conducted to determine independent predictors of 1-year mortality. Finally, ROC curves were used to compare AUC of RDW, CCI and the combination of both in predicting 1-year mortality.

RESULTS

The mean RDW was 13.6% ± 1.2. Eighteen percent of patients had pre-operative anemia. The mean CCI was 0.4 ± 0.9. RDW, anemia, CCI, and age were significantly associated with a higher incidence of 1-year mortality. RDW, CCI, age, and male sex were found to be independent risk factors for 1-year mortality. RDW (AUC = 0.68) was a better predictor of mortality compared to CCI (AUC = 0.66). The combination of RDW and CCI (AUC = 0.76) predicted 1-year mortality more accurately than CCI or RDW alone.

CONCLUSION

RDW appears to be a useful parameter that, when combined with CCI, can predict the risk for 1-year mortality after TJA.

High red blood cell distribution width levels could increase the risk of hemorrhagic transformation after intravenous thrombolysis in acute ischemic stroke patients

The association between the red blood cell distribution width (RDW) and hemorrhagic transformation (HT) after thrombolysis in acute ischemic stroke patients remains inconclusive. Our study aimed to assess whether high RDW levels are associated with the occurrence of HT after thrombolysis. Data were consecutively collected and retrospectively analyzed for stroke patients treated with thrombolysis between 1 January 2017 and 31 December 2019. The primary outcomes were the occurrence of HT and symptomatic HT. Among the 286 patients enrolled, 36 (12.6%) developed HT and15 (5.2%) were classified as symptomatic HT. Patients with high RDW levels were associated with a higher percentage of HT and symptomatic HT (P<0.05). The RDW levels in the HT and symptomatic HT groups were also greater compared with the no-HT group (P<0.001). Multivariable logistic regression analysis revealed that high RDW levels were independently associated with an increased risk of HT (adjusted odds ratio 2.5, 95 % CI, 1.74–3.83 P < 0.001). In conclusion, we found that high RDW levels may be an independent predictor of HT in stroke patients after thrombolysis.

Relation of red cell distribution width with HAS-BLED score in patients with non-valvular atrial fibrillation

Background

Numerous researchers have shown that there is a close correlation between red cell distribution width (RDW) and cardiovascular disease such as heart failure, coronary heart disease, and atrial fibrillation. This study was designated to investigate the correlation between RDW and the Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile international normalized ratio, Elderly, Drugs/alcohol (HAS-BLED) score.

Methods

The HAS-BLED scores of 251 hospitalized patients with non-valvular atrial fibrillation were calculated and the receiver operating characteristics were used to evaluate the predictive value of RDW on high HAS-BLED score (≥3 scores). Multiple logistic regression analysis was used to analyze the independent predictor of high HAS-BLED scores.

Results

Correlation analysis between RDW and HAS-BLED scores showed the RDW was positively correlated with HAS-BLED score, with r=0.393 (P<0.0001). The RDW of the high HAS-BLED score group was higher than that of the no-high HAS-BLED score group. The area under the receiver operating characteristic curve of RDW was 0.796 (0.740–0.844, P<0.0001) to predict a high HAS-BLED score, and multiple logistic regression analysis showed that a high RDW value could be used as an independent predictor of high HAS-BLED.

Conclusions

RDW value is associated with HAS-BLED value, and can be used as the independent predictive factor of high HAS-BLED scores.

The associations between red cell distribution width and plasma proteins in a general population

Background

High red cell distribution width (RDW) has been increasingly recognized as a risk factor for cardiovascular diseases (CVDs), but the underlying mechanisms remain unknown. Our aim was to explore the associations between RDW and plasma proteins implicated in the pathogenesis of CVD using a targeted proteomics panel.

Methods

RDW and 88 plasma proteins were measured in a population-based cohort study (n = 4726), Malmö Diet and Cancer-Cardiovascular Cohort (MDC-CC). A random 2/3 of the cohort was used as discovery sample and remaining 1/3 was used for replication. Multiple linear regression was used to assess the associations between RDW and plasma proteins, with adjustments for age, sex, and other potential confounders. Proteins with Bonferroni-corrected significant associations with RDW in the discovery sub-cohort were validated in the replication cohort.

Results

Thirteen of 88 plasma proteins had significant associations with RDW in the discovery sample, after multivariate adjustments. Eleven of them were also significant in the replication sample, including SIR2-like protein 2 (SIRT2), stem cell factor (SCF, inversely), melusin (ITGB1BP2), growth differentiation factor-15 (GDF-15), matrix metalloproteinase-7 (MMP-7), hepatocyte growth factor (HGF), chitinase-3-like protein 1 (CHI3L1), interleukin-8 (IL-8), CD40 ligand (CD40-L), urokinase plasminogen activator surface receptor (U-PAR) and matrix metalloproteinase-3 (MMP-3).

Conclusions

Several proteins from this targeted proteomics panel were associated with RDW in this cohort. These proteins could potentially be linked to the increased cardiovascular risk in individuals with high RDW.

Elevated Red Blood Cell Distribution Width May Be a Novel Independent Predictor of Poor Functional Outcome in Patients Treated with Mechanical Thrombectomy

Purpose

Red blood cell distribution width (RDW) evaluates the variation (size heterogeneity) in red blood cells. Elevated RDW has been identified as a predictor of poor functional outcomes for acute ischemic stroke. The association between elevated RDW level and poor functional outcome in stroke patients undergoing mechanical thrombectomy has not been reported before. This study aims to investigate this relationship.

Materials and Methods

This was a multicenter retrospective study involving the prospectively and consecutively collected data of 205 adult stroke patients who underwent mechanical thrombectomy for anterior circulation large vessel occlusion (middle cerebral artery M1, anterior cerebral artery A1, tandem ICA-MCA, carotid T) between July 2017 and December 2019. RDW cut off levels were accepted as >16%. The effect of elevated RDW on poor functional outcome (modified Rankin scale 3–6) was investigated using bivariate and multivariate regression analysis.

Results

Elevated RDW was significantly associated with poor functional outcome in bivariate and multivariate analysis (odds ratio [OR] for RDW >16%, 2.078; 95% confidence interval [95% CI], 1.083–3.966; P=0.027 and OR for RDW >16%, 2.873; 95% CI, 1.342–6.151; P=0.007; respectively).

Conclusion

These findings suggest that elevated RDW may be an independent predictor of poor functional outcomes in ischemic stroke patients undergoing mechanical thrombectomy.

Red Cell Distribution Width and Risk of Atrial Fibrillation and Subsequent Thromboembolism: The Tromsø Study

Introduction  Red cell distribution width (RDW) is associated with cardiovascular diseases, including atrial fibrillation (AF) and venous thromboembolism (VTE). Whether RDW is a risk marker for thromboembolic events in AF patients is scarcely known. We aimed to assess the association between RDW and the risk of AF, and AF-related VTE and ischemic stroke, in a population-based cohort.

Methods  We measured RDW in 26,111 participants from the Tromsø Study (1994–1995), and registered incident AF cases through December 31, 2013. Among participants with AF, first-ever VTEs and ischemic strokes were registered from the date of AF diagnosis through the end of follow-up. We calculated hazard ratios (HRs) with 95% confidence intervals (CIs) for AF by quartiles of RDW. Furthermore, we calculated cause-specific HRs for VTE and ischemic stroke by tertiles of RDW for participants with AF.

Results  There were 2,081 incident AF cases during a median of 18.8 years of follow-up. Subjects with RDW in the highest quartile (RDW ≥ 13.3%) had 30% higher risk of AF than those in the lowest quartile (RDW ≤ 12.3%). Among those with AF, subjects with RDW in the upper tertile had a doubled risk of ischemic stroke (HR 2.07, 95% CI 1.20–3.57). In contrast, RDW was not associated with incident VTE in subjects with AF.

Conclusion  RDW was significantly associated with incident AF in a general population. Among subjects with AF, high RDW was associated with ischemic stroke, but not VTE.

Incidence and risk factors associated with postoperative stroke in the elderly patients undergoing hip fracture surgery

OBJECTIVES

Stroke is one of the rare but devastating complications after hip fracture in the elderly. By far, there is still scarce data on postoperative stroke in elderly patients with hip fractures.

METHODS

This was a retrospective study of prospectively collected data. Between October 2014 to December 2018, patients aged above 65 years who underwent operative treatment for hip fractures were included. Inpatient medical surveillance and scheduled telephone follow-up at 1, 3, 6, and 12 months after operation was conducted to identify who developed an incident stroke. Variables of interests were extracted from patients' inpatient medical records. Univariate analysis and multivariate logistic regression analysis were used to identify the independent risk factors associated with stroke.

RESULTS

During the study period, a total of 3743 patients were included, among whom 56 were found to have a stroke after operation, representing an incidence of 1.5% (95% CI, 1.1 to 1.9%). The multivariate analyses showed that advanced age (1-year increment; OR, 1.32; 95% CI, 1.08 to 1.48), history of previous stroke (OR, 4.79; 95% CI, 1.86 to 6.56), ASA III and above (OR, 2.62; 95% CI, 1.27 to 3.68), long-term use of aspirin (OR, 3.63; 95% CI, 1.41 to 4.78), and elevated RDW level (each increment of 1%, OR, 1.21; 95% CI, 1.02 to 1.36) were independently associated with postoperative stroke.

CONCLUSIONS

Although most are not modifiable, these risk factors help in counseling patients regarding the risk of postoperative stroke, individual risk stratification, and targeted optimization of medical conditions and should be firmly kept in treating surgeon's mind.

Biomarkers for Predicting Left Atrial or Left Atrial Appendage Thrombus in Anticoagulated Patients with Nonvalvular Atrial Fibrillation

Purpose

Although atrial fibrillation (AF) is often associated with thromboembolic complications, there is no definite biomarker for detecting the presence of thrombi in the left atrial (LA) or left atrial appendage (LAA) in patients with nonvalvular atrial fibrillation (NVAF).

Methods

NVAF patients who underwent transesophageal echocardiography (TEE) to evaluate LA/LAA thrombus and spontaneous echo contrast (SEC) before AF ablation were included. Multivariate logistic regression and receiver operating characteristic curve (ROC) analyses were performed to explore the independent risk factors of LA/LAA thrombus and indicate the best cutoff point.

Results

Of the 260 consecutive subjects (mean age: 63.67 ± 9.39 years; 42% women), 45 (17.3%) patients were with LA/LAA thrombus, 131 (50.4%) were with SEC, and 84 (32.3%) were with neither thrombus nor SEC. The results of multivariate logistic regression analysis showed that N-terminal pro-B-type natriuretic peptide (NT-proBNP) (OR, 2.179; 95% CI: 1.191–3.987; p=0.012) and red cell distribution width (RDW) (OR, 2.398; 95% CI: 1.075–5.349; p=0.033) were independently correlated with the presence of LA/LAA thrombus but not D-dimer (OR, 0.999; 95% CI: 0.998–1.000; p=0.210). When all patients were divided into four groups based on the combination between RDW (cutoff value: 12.95%) and NT-proBNP levels (cutoff value: 368.9 ng/L), the rate of LA/LAA thrombus was the highest in the high RDW and NT-proBNP group.

Conclusion

In anticoagulation patients with NVAF, elevated NT-proBNP and RDW are related to LA/LAA thrombus. Therefore, these might be considered as useful prognostic markers in the management and treatment of NVAF patients.

The predictive value of red cell distribution width for stroke severity and outcome

Objectives

In the present study, we sought to investigate the association between red cell distribution width (RDW) and stroke severity and outcome in patients who underwent anti-thrombolytic therapy with tissue plasminogen activator (tPA).

Results

In this prospective study, 282 stroke patients who underwent tPA injection were included. The categorization of RDW to < 12.9% and > 13% values revealed insignificant difference in stroke severity score, accounting for the mean 36-h NIHSS of 8.19 ± 8.2 in normal RDW values and 9.94 ± 8.28in higher RDW group (p = 0.64). In seventh day, NIHSS was 6.46 ± 7.28 in normal RDW group and was 8.52 ± 8.35 in increased RDW group (p = 0.058). Neither the 36-h, nor the seventh day and 3-month mRS demonstrated significant difference between those with normal and higher RDW values.

Red Cell Distribution Width Is a Risk Factor for Hip Fracture in Elderly Men Without Anemia

Red cell distribution width (RDW), routinely assessed as a component of a complete blood count (CBC), quantifies the variation in the size of red blood cells. It increases with age, and increased RDW predicts many aging-related diseases and mortality. However, whether it also predicts hip fracture is unknown. We prospectively evaluated the association between RDW and hip fracture using data from the Osteoporotic Fracture in Men (MrOS) study. RDW was measured in 3635 men (aged 71 to 99 years) along with bone mineral density (BMD) in MrOS. RDW ranged from 11.3% to 32.9% (median 14.0%; interquartile range 13.5% to 14.8%) and was categorized into four groups (≤13.0%, 13.1% to 14.0%, 14.1% to 15.0%, ≥15.1%). Study participants with a hemoglobin level <13.0 g/dL were classified as having anemia. During an average 8.1 years, 164 men suffered hip fractures. The risks of hip fractures increased with increase of RDW category. Furthermore, there was a significant interaction between anemia and RDW: An association between RDW and hip fractures was only observed in participants without anemia. In those without anemia, the relative hazard of hip fractures increased with increases in RDW category: Men in the highest RDW category had a 2.8 times higher risk of hip fractures than men in the lowest group (95% confidence interval 1.1 to 7.1). The risks of all-clinical fractures were also increased along with higher RDW values. Additionally, RDW was significantly associated with the risk of having a fall but not with femoral neck or total hip BMD. In conclusion, RDW and anemia defined by hemoglobin are widely available routine laboratory measurements that together could indicate increased risk of hip fracture, reflecting the neuromuscular effects of aging rather than lower hip BMD. © 2020 American Society for Bone and Mineral Research.

CYP2B6 Polymorphisms Are Associated with Ischemic Stroke Risk in a Chinese Han Population

Genetic factors have been demonstrated to play an important role in the pathology of ischemic stroke (IS). This study was conducted to explore the association between CYP2B6 polymorphisms and IS risk in a Chinese Han population. Four single-nucleotide polymorphisms (SNPs) in CYP2B6 from 477 cases and 495 controls were genotyped using the Agena MassARRAY. The odds ratio (OR) and 95% confidence interval (CI) were calculated under genetic models and haplotype analysis to assess the association between SNPs and IS risk. We found that rs2099361 was associated with an increased IS risk (CC vs. AA: overall: OR = 1.85, 95% CI: 1.16-2.93, P = 0.010; age ≤ 60: OR = 1.94, 95% CI: 1.02-3.70, P = 0.045; male: OR = 2.17, 95% CI: 1.22-3.86, P = 0.009). The GT genotype of rs4803420 was associated with a reduced IS risk (OR = 0.74, 95% CI: 0.57-0.98, P = 0.036); the GG genotype was associated with an increased IS risk in women (OR = 2.31, 95% CI: 1.00-5.31, P = 0.049). The rs1038376 polymorphism was associated with reduced IS risk for age ≤ 60 years (AT vs. TT: OR = 0.63, 95% CI: 0.40-0.99, P = 0.046). Interestingly, there were significant differences in some clinical indicator levels between case and control groups, and genotypes of SNPs. Our results indicated that CYP2B6 polymorphisms (rs2099361, rs4803420, and rs1038376) were associated with the risk of IS. Further studies are still needed to validate our findings with larger sample sizes.

Alterations of lymphocyte count and platelet volume precede cerebrovascular lesions in stroke-prone spontaneously hypertensive rats

Background: Cerebral small vessel disease (CSVD) is associated with future stroke. Although pathological alteration in small vessels of patients with CSVD can be detected by neuroimaging, diagnosis of CSVD is delayed because it is an asymptomatic disease. The stroke-prone spontaneously hypertensive rat (SHRSP) show similar pathological features to human CSVD and develop stroke-related symptoms with advancing age.Objective: We investigated the time course of haematological parameters in Wistar rats and SHRSP.Material and Methods: Blood cells were analysed using an automated haematological analyser.Results: SHRSP develop stroke-related symptoms including onset of neurological symptoms, decreased body weight and blood brain barrier leakage between 12 and 14 weeks of age. Lymphocyte counts were gradually decreased at 3 weeks before development of stoke-related symptoms and then were further decreased after the development of stroke-related symptoms. The both mean platelet volume and large platelet ratio gradually increased at 3 weeks before the development of stoke-related symptoms. However, although SHRSP showed more microcytic red cells than Wistar rats, the trajectories of change in erythrocyte-related parameters were similar between Wistar rats and SHRSP.Conclusion: Our pilot study suggests that alterations of lymphocyte count and platelet volume predictive indicators for asymptomatic CSVD and symptomatic stroke in SHRSP.

Association between red cell distribution width level and risk of stroke: A systematic review and meta-analysis of prospective studies

BACKGROUND

Red cell distribution width level may have relations with the incidence and prognosis of cerebrovascular diseases. Recent researches have reported that red cell distribution width level was linked to the occurrence of stroke. However, the predicted effect of red cell distribution width in stroke is still disputed. We sought to assess the relationship between red cell distribution width and risk of stroke in this meta-analysis.

METHODS

Relevant studies were picked out from the databases of Embase, PubMed, and Cochrane Library. Hazard ratio with 95% confidence interval was chosen to analyze each trial, which was extracted from results of the highest and lowest red cell distribution width group. Funnel plots, Begg and Egger test were used to assess publication bias in the meta-analysis. Stata(12.0) was utilized to perform statistic analysis in the process.

RESULTS

A total of 6 studies with 5783 patients were included in this meta-analysis. The results showed that red cell distribution width level in patients with stroke was significantly higher than it in those without stroke (HR = 1.34, 95%CI:1.23-1.47, P < .001), in particular ischemic stroke(HR = 1.34,95% confidence interval:1.1-1.54, P < .001). There was no evidence of heterogeneity across the studies (P = .355, I = 5.53%).

CONCLUSIONS

The higher red cell distribution width level was associated with an increased risk of stroke, especially ischemic infarction.

Red Cell Distribution Width as a Novel Prognostic Marker in Multiple Clinical Studies

Red cell distribution width (RDW), which is a quantitative method applied for the measurement of anisocytosis, is the most reliable and inexpensive method for differentiation of iron deficiency anemia and thalassemia trait. An increase in its rate reflects a great heterogeneity in the size of red blood cells (RBCs). Recent studies have shown a significant relationship between RDW and the risk of morbidity and mortality in patients with multiple diseases. A strong association is established between changes in RDW and the risk of adverse outcome in patients with heart failure in multiple studies. In this review, we try to focus on the association and correlation between the increase in RDW and different outcomes of common diseases that may be related to RDW and based on the results of various studies, we are trying to introduce RDW as a diagnostic indicator for these diseases.

Baseline Red Blood Cell Distribution Width as a Predictor of Stroke Occurrence and Outcome: A Comprehensive Meta-Analysis of 31 Studies

Background: Red blood cell distribution width (RDW) may be a potential biomarker of inflammation in patients with stroke. Elevated RDW is associated with higher incidence of stroke, unfavorable functional outcome, and increased mortality, although results are inconsistent in the reported literature. This study aims to evaluate the predictive power of RDW regarding stroke occurrence and outcome. Methods: A thorough literature search was conducted utilizing the PubMed Central (PMC) and EMBASE databases to identify studies up to May 2019. Data from these studies were pooled, and combined odds ratios/risk ratios (ORs/RRs) were estimated for the risk of stroke, functional outcome, and mortality. A subgroup analysis was also performed to explore heterogeneity in terms of population status, demographic factors (age, gender distribution, and country), and vascular risk factors (hypertension, diabetes mellitus, and current smoking). Results: A total of 31 studies with 3,487,896 patients were included in the analysis. Elevated RDW was found to be a risk factor in ischemic stroke (OR/RR 1.528; 95% confidence interval [CI] = 1.372-1.703), whereas combined OR in subarachnoid hemorrhage (SAH) was not statistically significant (OR/RR 1.835; 95% CI = 0.888-3.792). Elevated RDW posed increased risk in populations with conventionally higher risk of stroke, such as atrial fibrillation (AF) (OR/RR 1.292; 95% CI = 1.107-1.508) and diabetes mellitus (OR/RR 2.101; 95% CI = 1.488-2.968), and in community cohorts (OR/RR 1.245; 95% CI = 1.216-1.275). In addition, higher RDW was associated with unfavorable functional outcome, either at discharge (OR/RR 1.220; 95% CI = 1.070-1.39) or at 90 days (OR/RR 1.277; 95% CI = 1.155-1.413). Higher mortality was found in patients with increased RDW (OR/RR 1.278; 95% CI = 1.221-1.337), independent of demographic factors (age, gender distribution, and country). Conclusions: Baseline RDW should be integrated into clinical practice as a predictor of ischemic stroke occurrence and outcome. Future studies should also explore the dynamic change of RDW in post-stroke patients to evaluate the clinical significance of RDW and its impact on the inflammatory state of ischemic stroke.

The relationship between red cell distribution width and all-cause and cause-specific mortality in a general population

Red Cell Distribution Width (RDW) could be a risk factor for developing various chronic diseases, and seems to be a prognostic marker in patients with cardiovascular disease (CVD) or cancer. Our aim was to explore the association between RDW and all-cause and cause-specific mortality in a general population. RDW was measured in 27,063 participants (aged 45–73 years) from the population-based Malmö Diet and Cancer cohort. After a follow-up of 19.8 ± 5.5 years, Cox proportional hazards regression analysis was used to study the relationship between RDW and all-cause and cause-specific mortality, with adjustment for confounding factors. A total of 9388 individuals (4715 men and 4673 women) died during the follow up. High RDW was significantly associated with all-cause mortality (HR, 4^th vs. 1^st quartile: 1.34, 95%CI: 1.24–1.45), cancer mortality (HR: 1.27, 95%CI: 1.12–1.44), CVD mortality (HR: 1.39, 95%CI: 1.21–1.59), and respiratory disease mortality (HR: 1.47, 95%CI: 1.06–2.03). The C-statistic increased significantly from 0.732 to 0.737 when adding RDW to a model adjusted for age and sex. There was a significant interaction between RDW and BMI with respect to all-cause mortality. We concluded that RDW is associated with mortality and propose that high RDW is a significant, but non-specific marker of mortality risk in the general population.

The role of red blood cell distribution width (RDW) in cardiovascular risk assessment: useful or hype?

Red blood cell distribution width (RDW) reflects erythrocyte size distribution, thus representing a reliable index of anisocytosis, widely used for the differential diagnosis of micro- and normocytic anaemias. Along with the large use in diagnostic hematology, RDW has been associated with presence and complications of a vast array of human pathologies during the last decades, including cardiovascular (CV) diseases. This article is hence aimed to provide an overview of important studies and systematic reviews with meta-analysis, in which RDW has been associated with CV events and mortality, in the attempt of establishing whether enough evidence exists for supporting its routine use in clinical practice. According to available data it seems reasonable to conclude that although the diagnostic specificity is low, and this measure is still plagued by important lack of standardization, RDW can be regarded as an index of enhanced patient fragility and higher vulnerability to adverse outcomes. Abnormal RDW values shall hence persuade physicians to broaden the diagnostic reasoning over anaemias, especially those due to malnutrition or malabsorption, encompassing a comprehensive assessment of traditional and non-traditional CV risk factors.

Correlation Between Red Cell Distribution Width and Peripheral Vascular Disease Severity and Complexity

A traditional hematological marker, red cell distribution width (RDW), is accepted as a novel marker of atherosclerotic vascular diseases. Clinical importance of the RDW as a prognostic biomarker in peripheral vascular disease (PVD) has been reported in a few studies. Herein, we aimed to show the correlation between RDW and PVD severity and its complexity in terms of angiographic evaluation. A total of 118 patients who underwent peripheral lower extremity angiography were subsequently evaluated retrospectively. Upon admission, RDW level was measured with automated complete blood count. Severity and complexity of the PVD was evaluated according to Trans-Atlantic Inter-Society Consensus (TASC II) classification. A TASC II A-B lesion was defined as simple PVD, and a TASC II C-D lesion was defined as prevalent and complex PVD. Then, both groups were compared statistically according to clinical, laboratory, and demographic features, including RDW levels. In 49.6% of the patients, TASC II C-D lesions were observed. Advanced age, male gender, and body mass index (BMI) were associated with TASC II groups. Red cell distribution width levels were correlated with presence of PVD, as well as TASC II grades (p:0.02). The fourth quartile (75th percentile) of the RDW levels was 14.1, and patients with RDW levels ≥14.1 had a more significant correlation with the presence and severity of PVD (p:0.001). In the multivariate regression analysis, elevated RDW was found to be an independent predictor of the presence of PVD and also TASC II C-D lesions (OR:2.26, with a 95% confidence interval (CI) 0.051-0.774; p:0.02). Elevated RDW levels was associated with TASC II C-D lesions, which indicated more prevalent and complex PVD.

Red cell distribution width associations with clinical outcomes: A population-based cohort study

Importance

Higher levels of red cell distribution width (RDW) are associated with adverse outcomes, especially in selected cohorts with or at risk for chronic disease. Whether higher RDW or the related parameter standard deviation of the red blood cell distribution (SD-RBC) can predict a broader range of outcomes in the general population is unknown.

Objective

To evaluate the association of RDW and SD-RBC with the risk of adverse outcomes in people from the general population.

Design

Population-based retrospective cohort study.

Setting

Health care system in a Canadian province (Alberta).

Participants

All 3,156,863 adults living in Alberta, Canada with at least one measure of RDW and SD-RBC between 2003 and 2016. Data were analyzed in September 2018.

Exposure

RDW and SD-RBC, classified into percentiles (<1, 1–5, 5–25, 25–75, 75–95, 95–99, >99).

Main outcomes

All-cause death, first myocardial infarction, first stroke or transient ischemic attack, placement into long-term care (LTC), progression to renal replacement therapy (initiation of chronic dialysis or pre-emptive kidney transplantation), incident solid malignancy, and first hospitalization during follow-up.

Results

Over median follow-up of 6.8 years, 209,991 of 3,156,863 participants (6.7%) died. The risk of death increased with increasing RDW percentile. After adjustment, and compared to RDW in the 25^th to 75^th percentiles, the risk of death was lower for participants in the <25^th percentiles but higher for participants in the 75^th-95^th percentiles (HR 1.42, 95% CI 1.40,1.43), the 95^th-99^th percentiles (HR 1.86, 95% CI 1.83,1.89) and the >99^th percentile (HR 2.18, 95% CI 2.12,2.23). Similar results were observed for MI, stroke/TIA, incident cancer, hospitalization and LTC placement, but no association was found between RDW and ESRD. Findings were generally similar for SD-RBC, except that all associations tended to be stronger than for RDW, and both lower and higher values of SD-RBC were independently associated with ESRD.

Conclusion and relevance

RDW and SD-RBC may be useful as prognostic markers for people in the general population, especially for outcomes related to chronic illness. SD-RBC may be superior to RDW.

Abnormal red blood cell indices increase the risk of arterial ischemic stroke in children

A high red cell distribution width (RDW) and low hemoglobin level increase the risk of arterial ischemic stroke (AIS), mostly in adults. The mechanisms related to AIS remain unknown. A total of 233 subjects (90 patients and 143 healthy controls [HC]) were enrolled. The mean(SD) age in patients and HC was 9.5(3.8) and 11.4(1.8) years, respectively. We found increased odds ratios (ORs) for large vessel and small vessel subtypes in patients without underlying diseases with a mean corpuscular volume (MCV) <80 fL (OR: 5.4, 95%CI 1.8-16.3 and 2.8, 95%CI 1.2-7.2), mean corpuscular hemoglobin levels <27 pg (OR: 2.9, 95%CI 1.0-6.7 and 2.6, 95%CI 1.0-6.7), and RDW >15% (OR: 5.5, 95%CI 1.3-24.5 and 2.7, 95%CI 1.0-7.3). RBC indices showed significant correlations with TM levels. Therefore, low MCV and MCH levels, and a high RDW were risk factors for AIS and associated with TM levels in this population.

Impact of Chronic Inflammation, Assessed by hs-CRP, on the Association between Red Cell Distribution Width and Arterial Cardiovascular Disease: The Tromsø Study

Red cell distribution width (RDW), a measure of variability in size of circulating erythrocytes, is associated with arterial cardiovascular disease (CVD), but the underlying mechanism remains unclear. We aimed to investigate the impact of chronic inflammation as measured by high-sensitivity C-reactive protein (hs-CRP) on this relationship, and explore whether RDW could be a mediator in the causal pathway between inflammation and arterial CVD. Baseline characteristics, including RDW and hs-CRP, were obtained from 5,765 individuals attending a population-based cohort study. We followed up participants from inclusion in the fourth survey of the Tromsø Study (1994/1995) until December 31, 2012. Multivariable Cox-regression models were used to calculate hazard ratios (HR) with 95% confidence intervals (CI) for incident myocardial infarction (MI) and ischemic stroke across quintiles of hs-CRP and RDW. Subjects with hs-CRP in the highest quintile had 44% higher risk of MI (HR: 1.44, 95% CI: 1.14-1.80), and 64% higher risk of ischemic stroke (HR: 1.64, 95% CI: 1.20-2.24) compared with subjects in the lowest quintile. RDW mediated 7.2% (95% CI: 4.0-30.8%) of the association between hs-CRP and ischemic stroke. Subjects with RDW in the highest quintile had 22% higher risk of MI (HR: 1.22, 95% CI: 0.98-1.54) and 44% higher risk of ischemic stroke (HR: 1.44, 95% CI: 1.06-1.97) compared with subjects in the lowest quintile. These risk estimates were slightly attenuated after adjustments for hs-CRP. Our findings suggest that chronic inflammation is not a primary mechanism underlying the relationship between RDW and arterial CVD.

The association between red cell distribution width and venous thromboembolism is not explained by myocardial infarction, stroke, or cancer

BACKGROUND

Red cell distribution width (RDW) is a risk marker of venous thromboembolism (VTE), myocardial infarction (MI), stroke, and cancer. Due to interrelations between these diseases, the association between RDW and VTE may be explained by MI, stroke, or cancer.

OBJECTIVE

To investigate whether the effect of RDW on VTE could be explained by intermediate development of MI, stroke, or cancer.

METHODS

RDW was measured in 24 363 participants of the Tromsø Study in 1994-1995. Incident VTE, MI, stroke, and cancer were registered until December 31, 2010. Conventional and cause-specific Cox-regression models were used to estimate hazard ratios (HR) for VTE with 95% confidence intervals (CI) across categories of RDW.

RESULTS

There were 502 first VTEs during a median follow-up of 16 years. In conventional Cox regression analysis, RDW in the highest quartile was associated with a 71% (HR 1.71, 95% CI 1.09-2.67) and 27% (HR 1.27, 95% CI 0.88-1.85) higher risk of VTE in men and women, respectively, compared to subjects in the lowest quartiles. The risk of VTE among subjects with RDW in the highest quartile was similar for men and women of postmenopausal age. In cause-specific analysis, where each individual contributed with person-time until the first occurring event only, the risk estimates were similar to those of the conventional Cox-regression analysis.

CONCLUSION

Our findings suggest that the association between RDW and future risk of VTE is not explained by intermediate development of MI, stroke, or cancer.

Elements of the complete blood count associated with cardiovascular disease incidence: Findings from the EPIC-NL cohort study

All blood cells (white blood cells [WBC], red blood cells [RBC] and platelets) can play a role in atherosclerosis. Complete blood count (CBC) is widely available in clinical practice but utility as potential risk factors for cardiovascular disease (CVD) is uncertain. Our aim was to assess the associations of pre-diagnostic CBC with incidence of CVD in 14,362 adults free of CVD and aged 47.8 (±11.7) years at baseline, followed-up for 11.4 years (992 incident cases). Cox proportional hazards regressions were used to estimate HRs and 95%CI. Comparing the top (T3) to bottom (T1) tertile, increased total WBC, lymphocyte, monocyte and neutrophil counts were associated with higher CVD risk: 1.31 (1.10; 1.55), 1.20 (1.02; 1.41), 1.21 (1.03; 1.41) and 1.24 (1.05; 1.47), as well as mean corpuscular volume (MCV: 1.23 [1.04; 1.46]) and red cell distribution width (RDW: 1.22 [1.03; 1.44]). Platelets displayed an association for count values above the clinically normal range: 1.49 (1.00; 2.22). To conclude, total and differential WBC count, MCV, RDW and platelet count likely play a role in the aetiology of CVD but only WBC provide a modest improvement for the prediction of 10-year CVD risk over traditional CVD risk factors in a general population.

Red Blood Cell Distribution Width: A Novel Predictive Indicator for Cardiovascular and Cerebrovascular Diseases

The red blood cell distribution width (RDW) obtained from a standard complete blood count (CBC) is a convenient and inexpensive biochemical parameter representing the variability in size of circulating erythrocytes. Over the past few decades, RDW with mean corpuscular volume (MCV) has been used to identify quite a few hematological system diseases including iron-deficiency anemia and bone marrow dysfunction. In recent years, many clinical studies have proved that the alterations of RDW levels may be associated with the incidence and prognosis in many cardiovascular and cerebrovascular diseases (CVDs). Therefore, early detection and intervention in time of these vascular diseases is critical for delaying their progression. RDW as a new predictive marker and an independent risk factor plays a significant role in assessing the severity and progression of CVDs. However, the mechanisms of the association between RDW and the prognosis of CVDs remain unclear. In this review, we will provide an overview of the representative literatures concerning hypothetical and potential epidemiological associations between RDW and CVDs and discuss the underlying mechanisms.

Red blood cells in thrombosis

Red blood cells (RBCs) have historically been considered passive bystanders in thrombosis. However, clinical and epidemiological studies have associated quantitative and qualitative abnormalities in RBCs, including altered hematocrit, sickle cell disease, thalassemia, hemolytic anemias, and malaria, with both arterial and venous thrombosis. A growing body of mechanistic studies suggests that RBCs can promote thrombus formation and enhance thrombus stability. These findings suggest that RBCs may contribute to thrombosis pathophysiology and reveal potential strategies for therapeutically targeting RBCs to reduce thrombosis.

Red blood cell distribution width and ischaemic stroke

The red blood cell distribution width (RDW) is a measure of red blood cell (RBC) size heterogeneity, which is easily calculated by dividing the SD of erythrocyte volumes for the mean corpuscular volume. Recent reporter suggested that, besides haematological diseases and anaemia, many human disorders may be closely associated with the elevated RDW. A literature review has revealed the RDW may be closely related to the development of ischaemic stroke, carotid artery atherosclerosis and cerebral embolism. Higher RDW could independently predict adverse outcomes in patients in these conditions.

Routine hematological parameters are associated with short- and long-term prognosis of patients with ischemic stroke

BACKGROUND

Previous studies indicated that some routine hematological parameters are associated with the prognosis of ischemic stroke (IS), but none of study has evaluated them simultaneously. The aim of this study was to investigate the prognostic value of routine hematological parameters in IS patients.

METHODS

Using medical record database, we retrospectively reviewed the patients with IS admitted in Gansu Province Hospital between June 2014 and July 2015. The prognostic value of routine hematological parameters on admission was analyzed using logistic regression model, receiver operating characteristic (ROC) curve analysis and Cox proportional hazards model.

RESULTS

Patients with hospital mortality had significantly higher white blood cell (WBC), neutrophil, neutrophil to lymphocyte ratio (NLR), red blood cell distribution width (RDW) and National Institutes of Health Stroke Scale (NIHSS), while their lymphocyte, monocyte, and eosinophil were significantly lower. The area under ROC curve (AUC) for eosinophil, neutrophil, WBC, RDW, NLR, monocyte, and lymphocyte were 0.74 (95% CI, 0.67-0.82), 0.76 (95% CI, 0.67-0.84), 0.72 (95% CI, 0.64-0.81), 0.65 (95% CI, 0.56-0.73), 0.76 (95% CI, 0.68-0.84), 0.67 (95% CI, 0.59-0.76), and 0.75 (95% CI, 0.67-0.83), respectively. In a multivariable logistical regression model, only WBC, NLR, and NIHSS were independently associated with hospital mortality. In a multivariable model, age, NIHSS, RDW, NLR, and eosinophil were independent prognostic factors for all-cause mortality.

CONCLUSION

Red blood cell distribution width, NLR and eosinophil are independent prognostic factors for IS.

Red blood cell distribution width and neutrophil to lymphocyte ratio are associated with outcomes of adult subarachnoid haemorrhage patients admitted to intensive care unit

Background

Red blood cell distribution width (RDW) and neutrophil to lymphocyte ratio (NLR) have been reported to be associated with outcomes of acute cerebral infarction. However, their prognostic value in patients with subarachnoid haemorrhage (SAH) remains largely unknown. The aim of this study was to investigate the prognostic value of RDW and NLR in SAH patients.

Methods

Medical records of adult SAH patients admitted to intensive care unit (ICU) were extracted from Multiparameter Intelligent Monitoring in Intensive Care II (MIMIC II, version 2.6), a publicly accessible ICU database. Prognostic value of RDW and NLR was analysed using logistic regression model, Kaplan-Meier curve analysis and Cox regression model.

Results

A total of 274 SAH patients were included. Patients died in hospital had significantly higher RDW and NLR. RDW and NLR were significantly associated with hospital death, with adjusted odds ratios of 1.39 (95% CI, 1.06–1.82) and 1.04 (95% CI, 1.00–1.08), respectively. Furthermore, increased RDW and NLR were associated with higher one-year mortality, with an adjusted hazard ratio of 1.20 (95% CI, 1.02–1.41) for per 1% increased RDW and 1.03 (95% CI, 1.00–1.05) for per 1 increased NLR.

Conclusion

RDW and NLR are useful indices to evaluate the outcomes of ICU admitted patients with SAH.

Toward a Blood-Borne Biomarker of Chronic Hypoxemia: Red Cell Distribution Width and Respiratory Disease

Hypoxemia (systemic oxygen desaturation) marks the presence, risk, and progression of many diseases. Episodic or nocturnal hypoxemia can be challenging to detect and quantify. A sensitive, specific, and convenient marker of recent oxygen desaturation represents an unmet medical need. Observations of acclimatization to high altitude in humans and animals reveals several proteosomic, ventilatory, and hematological responses to low oxygen tension. Of these, increased red cell distribution width (RDW) appears to have the longest persistence. Literature review and analyses of a 2M patient database across the full disease pathome revealed that increased RDW is predictive of poor outcome for certain diseases including many if not all hypoxigenic conditions. Comprehensive review of diseases impacting the respiratory axis show many are associated with increased RDW and no apparent counterexamples. The mechanism linking RDW to outcome is unknown. Conjectural roles for iron deficiency, inflammation, and oxidative stress have not been born out experimentally. Sports-doping studies show that erythropoietin (EPO) injection can induce formation of unusually large red blood cells (RBC) in sufficient numbers to increase RDW. Because endogenous EPO responds strongly to hypoxemia, this molecule could potentially mediate a long-lived RDW response to low oxygenation. RDW may be a guidepost signaling that unexploited information is embedded in subtle RBC variation. Applying modern techniques of measurement and analysis to certain RBC characteristics may yield a more specific and sensitive marker of chronic pulmonary and circulatory diseases, sleep apnea, and opioid inhibition of breathing.