Prognostic value of red cell distribution width in patients with pulmonary embolism

Construction and validation of risk prediction models for pulmonary embolism in hospitalized patients based on different machine learning methods

Objective

This study aims to apply different machine learning (ML) methods to construct risk prediction models for pulmonary embolism (PE) in hospitalized patients, and to evaluate and compare the predictive efficacy and clinical benefit of each model.

Methods

We conducted a retrospective study involving 332 participants (172 PE positive cases and 160 PE negative cases) recruited from Guangdong Medical University. Participants were randomly divided into a training group (70%) and a validation group (30%). Baseline data were analyzed using univariate analysis, and potential independent risk factors associated with PE were further identified through univariate and multivariate logistic regression analysis. Six ML models, namely Logistic Regression (LR), Decision Tree (DT), Random Forest (RF), Naive Bayes (NB), Support Vector Machine (SVM), and AdaBoost were developed. The predictive efficacy of each model was compared using the receiver operating characteristic (ROC) curve analysis and the area under the curve (AUC). Clinical benefit was assessed using decision curve analysis (DCA).

Results

Logistic regression analysis identified lower extremity deep venous thrombosis, elevated D-dimer, shortened activated partial prothrombin time, and increased red blood cell distribution width as potential independent risk factors for PE. Among the six ML models, the RF model achieved the highest AUC of 0.778. Additionally, DCA consistently indicated that the RF model offered the greatest clinical benefit.

Conclusion

This study developed six ML models, with the RF model exhibiting the highest predictive efficacy and clinical benefit in the identification and prediction of PE occurrence in hospitalized patients.

Red cell distribution in critically ill patients with chronic obstructive pulmonary disease

BACKGROUND

Red blood cell distribution width (RDW) is associated with increased mortality risk in patients with chronic obstructive pulmonary disease (COPD). However, limited data are available for critically ill patients with COPD.

METHODS

Data from the Medical Information Mart for Intensive Care III V1.4 database were analyzed in this retrospective cohort research. The International Classification of Diseases codes were used to identify critically ill patients with COPD. The first value of RDW was extracted within the first 24 h after intensive care unit admission. The endpoint was 28-day all-cause mortality. Multivariable logistic regression analysis was performed to examine the relationship between RDW and 28-day mortality. Age, sex, ethnicity, anemia status, comorbidities, clinical therapy, and disease severity score were considered for subgroup analysis.

RESULTS

A total of 2,344 patients were included with mean (standard deviation) age of 72.3 (11.3) years, in which 1,739 (53.6%) patients were men. The increase in RDW was correlated with an increased risk of 28-day mortality in the multivariate logistic regression model (odds ratio [OR] 1.15; 95% confidence interval [CI] 1.09-1.21). In comparison with the low-RDW group, the middle and high-RDW groups tended to have higher risks of 28-day all-cause mortality (OR [95% CI] 1.03 [0.78-1.34]; OR [95% CI] 1.70 [1.29-2.22]; P trend < 0.0001). Subgroup analyses show no evidence of effect modifications on the correlation of RDW and 28-day all-cause mortality.

CONCLUSION

An increase in RDW was associated with an increased risk of 28-day all-cause mortality in critically ill patients with COPD. Further studies are required to investigate this association.

Body Iron Store and its Association with Risk of First Episode of Spontaneous Lower Extremity Deep Vein Thrombosis/ Pulmonary Embolism: A Case-Control Study

Background and objectives

The association between body iron stores and risk of deep vein thrombosis/ pulmonary embolism (DVT/ PE) has not been studied among Indian subjects. This study aimed to evaluate the same and also study the association between iron stores and recanalization of affected veins at week-12.

Methods

This Case-Control with follow-up study enrolled 85 consecutive adult (≥ 18 years) cases presenting with first episode of spontaneous, proximal lower extremity DVT/ PE and 170 age (± 3 years) and sex matched adult controls without DVT/ PE. Those with haemoglobin(Hb) < 9 g/dl, malignancies, serum creatinine ≥ 2 mg/dL, heart failure and concurrent infections/ inflammatory disorders were excluded. All participants underwent iron profile, serum ferritin light-chain (FtL) and hepcidin testing.

Results

Anaemia [OR = 2.3 (95% CI = 1.3-4.0), p = 0.001] and elevated RDW (RDW-CV > 15%) [OR = 2.3 (95% CI = 1.2-4.3), p = 0.012] were significantly associated with increased risk of DVT/ PE. Iron deficiency (ID, defined as serum ferritin < 30 µg/L, along with TSAT < 20%) was not associated with DVT/ PE risk [OR = 0.8 (95% CI = 0.4-1.7), p > 0.05]. Serum FtL in the highest quartile (> 75th centile) was associated with higher risk of DVT/ PE (OR = 5, 95% CI = 2.6-9.6) and levels < 25th centile with protection against DVT/ PE (OR = 0.1, 95% CI = 0.01-0.32), compared to levels between 25th and 75th centiles (referent range). Highest DVT/ PE risk was associated with FtL > 90th centile [OR≈12 (95% CI = 3.9-37.2)]. No associations were noted between serum hepcidin and DVT/ PE risk and ID and DVT recanalization at week-12.

Conclusion

Higher iron stores, rather than ID, were associated with increased risk of DVT/ PE among those with Hb ≥ 9 g/dL. Anaemia and elevated RDW were also associated with risk of DVT/ PE. ID was not associated with poorer DVT recanalization at week-12.

Association between red blood cell distribution width and all-cause mortality in unselected critically ill patients: Analysis of the MIMIC-III database

Background

Although red cell distribution width (RDW) is widely observed in clinical practice, only a few studies have looked at all-cause mortality in unselected critically ill patients, and there are even fewer studies on long-term mortality. The goal of our study was to explore the prediction and inference of mortality in unselected critically ill patients by assessing RDW levels.

Methods

We obtained demographic information, laboratory results, prevalence data, and vital signs from the unselected critically ill patients using the publicly available MIMIC-III database. We then used this information to analyze the association between baseline RDW levels and unselected critically ill patients using Cox proportional risk analysis, smoothed curve fitting, subgroup analysis, and Kaplan–Meier survival curves for short, intermediate, and long-term all-cause mortality in unselected critically ill patients.

Results

A total of 26,818 patients were included in our study for the final data analysis after screening in accordance with acceptable conditions. Our study investigated the relationship between RDW levels and all-cause mortality in a non-selected population by a smoothed curve fit plots and COX proportional risk regression models integrating cubic spline functions reported results about a non-linear relationship. In the fully adjusted model, we found that RDW values were positively associated with 30-day, 90-day, 365-day, and 4-year all-cause mortality in 26,818 non-selected adult patients with HRs of 1.10 95%CIs (1.08, 1.12); 1.11 95%CIs (1.10, 1.13); 1.13 95%CIs (1.12, 1.14); 1.13 95%CIs (1.12, 1.14).

Conclusion

In unselected critically ill patients, RDW levels were positively associated with all-cause mortality, with elevated RDW levels increasing all-cause mortality.

Association of cannabis use disorder with cardiovascular diseases: A two-sample Mendelian randomization study

Background

The use of cannabis has increased globally due to more regions decriminalizing marijuana use for therapeutic and recreational aims. Several observational studies have revealed that cannabis use is associated with an increased risk of adverse cardiovascular pathologies and diseases. Nevertheless, the causal associations between cannabis use and cardiovascular diseases remain unclear. Hence, we performed single-variable and multivariable Mendelian randomization (MR) to evaluate the association between cannabis use disorder and various cardiovascular diseases.

Materials and methods

Summary statistics were collected from the largest-to-date genome-wide association studies (GWAS) of cannabis use disorder. The 12 SNPs for cannabis use disorder were used as instrumental variables in this study. MR estimates were pooled using a random-effects inverse-variance weighted (IVW) method. Simple median and weighted median methods were conducted as sensitivity analyses.

Results

The genetic liability to cannabis use disorder was associated with an augmented risk of coronary artery disease, myocardial infarction, atrial fibrillation, heart failure, deep venous thrombosis, pulmonary embolism, and stroke. Except for stroke, the results were inconsistent in the sensitivity analyses. The overall patterns for the associations of cannabis use disorder with atrial fibrillation, heart failure, pulmonary embolism and stroke remained in multivariable MR analyses adjusting for potential mediators, including smoking, alcohol, body mass index, blood lipid, type 2 diabetes, hypertension, and depression. However, the association with coronary artery disease, myocardial infarction, and deep venous thrombosis did not persist in multivariable MR analyses. Mediation analysis demonstrated that smoking, body mass index, low-density lipoprotein, hypertension, and depression have more significant mediation effects, which suggests that these factors partly mediate the link from cannabis use disorder to coronary artery disease, myocardial infarction, and deep venous thrombosis.

Conclusion

The genetic liability to cannabis use disorder was associated with a higher risk of atrial fibrillation, heart failure, pulmonary embolism, and stroke. The evidence for the association between cannabis use disorder, coronary artery disease, myocardial infarction, and deep venous thrombosis was weak. Hence, future use of cannabis for therapeutic and recreational aims should consider its potential impact on cardiovascular diseases.

Diagnostic Accuracy of Multiple D-Dimer Cutoff Thresholds and Other Clinically Applicable Biomarkers for the Detection and Radiographic Evaluation of Pulmonary Embolism

Background: Diagnostic work-up of pulmonary embolism (PE) remains a challenge. Methods: We retrospectively studied all patients referred for computed tomography pulmonary angiography (CTPA) with suspicion of PE during a 12-month period (2018). The diagnostic accuracy of different D-dimer (Dd) cutoff thresholds for ruling out PE was evaluated. Furthermore, the association of Dd and red cell distribution width (RDW) with embolus location, CTPA findings, and patient outcome was recorded. Results: One thousand seventeen (n = 1017) patients were finally analyzed (mean age: 64.6 years (SD = 11.8), males: 549 (54%)). PE incidence was 18.7%. Central and bilateral embolism was present in 44.7% and 59.5%, respectively. Sensitivity and specificity for conventional and age-adjusted Dd cutoff was 98.2%, 7.9%, and 98.2%, 13.1%, respectively. A cutoff threshold (2.1 mg/L) with the best (64.4%) specificity was identified based on Receiver Operating Characteristics analysis. Moreover, a novel proposed Dd cutoff (0.74 mg/L) emerged with increased specificity (20.5%) and equal sensitivity (97%) compared to 0.5 mg/L, characterized by concurrent reduction (17.2%) in the number of performed CTPAs. Consolidation/atelectasis and unilateral pleural effusion were significantly associated with PE (p < 0.05, respectively). Patients with consolidation/atelectasis or intrapulmonary nodule(s)/mass on CTPA exhibited significantly greater median Dd values compared to patients without the aforementioned findings (2.34, (IQR 1.29−4.22) vs. 1.59, (IQR 0.81−2.96), and 2.39, (IQR 1.45−4.45) vs. 1.66, (IQR 0.84−3.12), p < 0.001, respectively). RDW was significantly greater in patients who died during hospitalization (p = 0.012). Conclusions: Age-adjusted Dd increased diagnostic accuracy of Dd testing without significantly decreasing the need for imaging. The proposed Dd value (0.74 mg/L) showed promise towards reducing considerably the need of CTPA. Multiple radiographic findings have been associated with increased Dd values in our study.

The prevalence and clinical features of pulmonary embolism in patients with AE-COPD: A meta-analysis and systematic review

BACKGROUND

The prevalence of pulmonary embolism (PE) in the acute exacerbation of chronic obstructive pulmonary disease (AE-COPD) is highly controversial. We conducted a systematic review and meta-analysis to summarize the epidemiology and characteristics of PE with AE-COPD for current studies.

METHODS

We searched the PubMed, EMBASE, Cochrane Library and Web of Science databases for studies published prior to October 21, 2020. Pooled proportions with 95% confidence intervals (95% CIs) were calculated using a random effects model. Odds ratios (ORs) and mean differences (MDs) with 95% confidence intervals were used as effect measures for dichotomous and continuous variables, respectively.

RESULTS

A total of 17 studies involving 3170 patients were included. The prevalence of PE and deep vein thrombosis (DVT) in AE-COPD patients was 17.2% (95% CI: 13.4%-21.3%) and 7.1% (95% CI: 3.7%-11.4%%), respectively. Dyspnea (OR = 6.77, 95% CI: 1.97-23.22), pleuritic chest pain (OR = 3.25, 95% CI: 2.06-5.12), lower limb asymmetry or edema (OR = 2.46, 95% CI:1.51-4.00), higher heart rates (MD = 20.51, 95% CI: 4.95-36.08), longer hospital stays (MD = 3.66, 95% CI: 3.01-4.31) were associated with the PE in the AE-COPD patients. Levels of D-dimer (MD = 1.51, 95% CI: 0.80-2.23), WBC counts (MD = 1.42, 95% CI: 0.14-2.70) were significantly higher and levels of PaO2 was lower (MD = -17.20, 95% CI: -33.94- -0.45, P<0.05) in the AE-COPD with PE group. The AE-COPD with PE group had increased risk of fatal outcome than the AE-COPD group (OR = 2.23, 95% CI: 1.43-3.50).

CONCLUSIONS

The prevalence of PE during AE-COPD varies considerably among the studies. AE-COPD patients with PE experienced an increased risk of death, especially among the ICU patients. Understanding the potential risk factors for PE may help clinicians identify AE-COPD patients at increased risk of PE.

PROSPERO REGISTRATION NUMBER

CRD42021226568.

Prognostic value of red blood cell distribution width in patients with acute pulmonary embolism: A protocol for systematic review and meta-analysis

BACKGROUND

Prior reports have suggested that the red blood cell distribution width (RDW) parameter could be measured as a prognostic indicator in pulmonary embolism (PE) patients, thereby helping to guide their care. However, no systematic analyses on this topic have been completed to date, and the exact relationship between RDW and PE remains to be fully clarified. We will therefore conduct a systematic literature review with the goal of defining the correlation between RDW and mortality in acute PE cases.

METHODS

The EMBASE, Web of Knowledge, PubMed, ClinicalTrials.gov, and Cochrane Library databases will be searched for all relevant studies published from inception through March 2021 using the following search strategy: ("red blood cell distribution width") AND ("pulmonary embolism"). Two authors will independently identify eligible studies and extract data. The Q and I2 statistics will be used to judge heterogeneity among studies.

RESULTS

This study will establish the relative efficacy of RDW as a metric for predicting PE patient mortality.

CONCLUSIONS

This study will offer a reliable, evidence-based foundation for the clinical utilization of RDW as a tool for gauging mortality risk in acute PE patients.

ETHICS AND DISSEMINATION

As this is a protocol for a systematic review of previously published data, no ethical approval is required. Electronic dissemination of study results will be done through a peer-review publication or represented at a related conference.

EVALUATION OF THE RELATIONSHIP OF MPV, RDW AND PVI PARAMETERS WITH DISEASE SEVERITY IN COVID-19 PATIENTS

Coronavirus was first detected in three severe pneumonia cases in Wuhan, China, in December 2019. Studies on red cell distribution width (RDW-CV) and mean platelet volume (MPV) laboratory parameters, which can be examined in complete blood count in COVID-19 patients, are still very limited. However, to the best of our knowledge, there are no studies examining the relationship between platelet volume index (PVI) and disease severity in COVID-19 patients, which was evaluated in this study. The aim of this study was to evaluate the relationship of disease severity in COVID-19 patients with their MPV, RDW, and PVI parameters. The study included 92 COVID-19 patients as a study group and 84 healthy individuals as control group. All laboratory data and radiological images were scanned retrospectively from patient files and hospital information system. Evaluation of the RDW-CV and MPV blood parameters, and PVI measured in COVID-19 patients yielded statistically significant differences according to the disease severity. We suggest that RDW-CV and PVI, evaluated within the scope of the study, may be the parameters that should be considered in the early diagnosis of the disease, from the initial stages of COVID-19. In addition, we think that the RDW-CV and MPV laboratory parameters, as well as PVI, which all are simple, inexpensive and widely used hematologic tests, can be used as important biomarkers in determining COVID-19 severity and mortality.

Predictive Value of Red Blood Cell Distribution Width in Chronic Obstructive Pulmonary Disease Patients with Pulmonary Embolism

Purpose

This study is aimed at investigating the relationship between red cell distribution width (RDW) and chronic obstructive pulmonary disease (COPD) patients with pulmonary embolism (PE).

Methods

We conducted a retrospective study enrolling a total of 125 patients from January 2013 to December 2019. The study group consisted of 40 COPD patients with PE, and the control group had 85 COPD patients without PE. Clinical data including demographic characteristics, comorbidities, and results of imaging examinations and laboratory tests were recorded. Blood biomarkers, including red blood cell distribution width standard deviation (RDW-SD), red blood cell distribution width coefficient of variation (RDW-CV), and D-Dimer, were included.

Results

RDW-SD and RDW-CV were higher in the COPD patients with the PE group (p < 0.001). A higher RDW-SD led to a significantly increased risk of PE than a lower RDW-SD (adjusted odds ratio (OR): 1.188; 95% confidence interval (CI): 1.048-1.348). The area under the curve (AUC) of RDW-SD used for predicting PE was 0.737. Using 44.55 as the cutoff value of RDW-SD, the sensitivity was 80% and the specificity was 64.7%. The prediction accuracy of RDW-SD combined with D-Dimer (AUC = 0.897) was higher than that of RDW-SD or D-Dimer alone. The optimal cutoff value of RDW-SD+D-Dimer for predicting PE was 0.266, which generated a sensitivity of 87.5% and specificity of 83.5%.

Conclusion

RDW is significantly increased in COPD patients with PE and may thus be useful in predicting the occurrence of PE in patients with COPD.

Patients Who Have Cannabis Use Disorder Have Higher Rates of Venous Thromboemboli, Readmission Rates, and Costs Following Primary Total Knee Arthroplasty

BACKGROUND

Studies have shown that cannabis can interfere with hematological parameters and platelet morphology. The purpose of this study is to investigate whether patients with cannabis use disorder undergoing primary total knee arthroplasty (TKA) have higher rates of (1) venous thromboemboli (VTEs); (2) readmissions; and (3) costs.

METHODS

Study group patients undergoing primary TKA were identified from a large, nationwide database. Patients who had a history of VTEs, deep vein thromboses (DVTs), pulmonary emboli (PEs), and coagulopathies before their TKA were excluded. Study group patients were matched to controls in a 1:4 ratio by age, sex, a comorbidity index, and medical comorbidities. The query yielded 18,388 patients (cannabis = 3680; controls = 14,708). Outcomes analyzed included rates of 90-day VTEs, DVTs, and PEs, in addition to 90-day readmissions and costs. A P value less than .01 was considered statistically significant.

RESULTS

Patients who have cannabis use disorder were found to have significantly higher incidence and odds (2.79% vs 1.78%; odds ratio [OR], 1.58; P < .0001) of VTEs, DVTs (2.41% vs 1.44%; OR, 1.68; P < .0001), and PEs (0.97% vs 0.62%; P = .01). Readmissions were significantly higher (27.03% vs 23.18%; OR, 1.22; P < .0001) in patients who have cannabis use disorder. Patients with cannabis use disorder have significantly higher day of surgery ($14,024.88 vs $12,127.49; P < .0001) and 90-day costs ($19,155.45 vs $16,315.00; P < .0001).

CONCLUSION

This study found that patients who have a cannabis use disorder have higher rates of thromboembolic complications, readmission rates, and costs following primary TKA compared to a matched cohort.

A narrative review of red blood cell distribution width as a marker for pulmonary embolism

Red blood cell distribution width (RDW) is a marker of variability in red blood cell size, and is routinely reported as part of a patient's complete blood count. RDW has been shown to be associated with the prediction, severity and prognosis of pulmonary embolism (PE) in recent studies. The underlying biomolecular mechanism of the relationship of RDW to PE is largely unknown, but is thought to be due to the relationship of RDW with acute inflammatory markers and variations in blood viscosity. This review substantiates that a high RDW level, defined using either an arbitrary number or according to receiver operator curve statistics, is associated with a higher risk of acute PE, increased severity (massive vs. submassive) of PE and increased mortality in patients with PE. Nevertheless, the comparison of current studies is limited due to the definition of high RDW (each study uses a different RDW cutoff level), the broad range of exclusion criteria and the inclusion of differing modalities used to diagnose a PE (computed tomography angiogram, ventilation-perfusion study, or clinical diagnosis). Despite the above limitations, these studies provide a promising future clinical use for RDW as a marker of PE.

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.

The role of increased red cell distribution width as a negative prognostic marker in patients with COPD

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) remains a major burden with no clinically applicable biomarkers.

AIM

To investigate the association of Red cell Distribution Width (RDW) values on admission with previous hospitalizations, need of non-invasive mechanical ventilation (NIMV) and long term oxygen therapy (LTOT) in patients with COPD.

METHODS

Patients with AECOPD admitted to our department during 2018 were included in the study.

RESULTS

One hundred sixty patients were enrolled (M/F 95/65, median age 71.00 years, mean FEV₁± SD = 46.6 ± 28.9). Median RDW was significantly higher for patients in need of NIMV (14.8, 95% CI: 14.2 to 15.6) than patients not in need of NIMV (13.5, 95% CI: 13.2 to 13.8) (p < 0.001). Median RDW was significantly higher for patients in need of LTOT (14.2, 95% CI: 13.7 to 14.6) compared to patients not receiving LTOT (13.2, 95% CI: 12.5 to 13.6) (p = 0.001). Patients with hospitalization during the last 12 months had increased RDW values compared to patients with no hospitalizations [median RDW 14.3, (95% CI: 13.5 to 14.9) versus median RDW 13.5, (95% CI: 13.1 to 13.9)](p = 0.001).

CONCLUSION

Patients with COPD in need of LTOT, NIMV or patients with previous hospitalizations presented with increased RDW values. Increased RDW values could serve as a negative prognostic marker in patients with COPD.

Value of the Delta Neutrophil Index for Predicting 28-Day Mortality in Patients With Acute Pulmonary Embolism in the Emergency Department

PURPOSE

Acute pulmonary embolism (PE), frequently seen in the emergency department (ED), is a leading cause of cardiovascular morbidity and mortality. The delta neutrophil index (DNI) reflects the fraction of circulating immature granulocytes as a component of the systemic inflammatory response syndrome criteria. The pathogenesis of acute PE is significantly associated with inflammation. The aim of the study was to investigate the clinical usefulness of the DNI as a marker of severity in patients with acute PE admitted to the ED.

METHODS

We retrospectively analyzed the data of patients who were diagnosed with acute PE at a single ED, admitted from January 1, 2011 to June 30, 2017. The diagnosis of acute pulmonary embolism was confirmed using clinical, laboratory, and radiological findings. The DNI was determined at presentation. The clinical outcome was all-cause mortality within 28 days of emergency department admission.

RESULTS

We included 447 patients in this study. The multivariate Cox regression model demonstrated that higher DNI values on ED admission were significantly associated with short-term mortality (hazard ratio, 1.107; 95% confidence interval, 1.042-1.177). The optimal cut-off DNI value, measured on ED admission, was 3.0%; this value was associated with an increased hazard of 28-day mortality following PE (HR, 7.447; 95% CI, 4.183-13.366; P < 0.001) CONCLUSION:: The DNI value, obtained as part of the complete blood count analysis, can be easily determined without additional burdens of cost or time. A high DNI is useful as a marker to predict 28-day mortality in patients with acute PE.

Red cell distribution width predicts out of hospital outcomes in critically ill emergency general surgery patients

Introduction

Red cell distribution width (RDW) is associated with mortality and bloodstream infection risk in critically ill patients. We hypothesized that an increase in RDW at hospital discharge in critically ill patients who received emergency general surgery (EGS) would be associated with increased mortality after hospital discharge.

Methods

We performed a two-center observational study of patients treated in medical and surgical intensive care units. We studied 1567 patients, who received critical care between 1998 and 2012 who underwent EGS and survived hospitalization. The exposure of interest was RDW within 24 hours of hospital discharge and categorized a priori in quintiles as ≤13.3%, 13.3% to 14.0%, 14.0% to 14.7%, 14.7% to 15.8%, 15.8% to 17.0% and >17.0%. The primary outcome was 90-day all-cause mortality. Adjusted ORs were estimated by multivariable logistic regression models with inclusion of covariate terms for age, race, gender, Deyo-Charlson Index, sepsis and number of organs with acute failure.

Results

The cohort patients were 51.4% male and 23.2% non-white. 23.9% had sepsis and the mean age was 58 years. 90-day postdischarge mortality was 6.8%. Patients with a discharge RDW 15.8% to 17.0% or RDW >17.0% have an adjusted OR of 90-day postdischarge mortality of 3.64 (95% CI 1.04 to 12.68; p=0.043) or 4.58 (95% CI 1.32 to 15.93; p=0.02), respectively, relative to patients with a discharge RDW ≤13.3%. Further, patients with a discharge RDW ≥15.8 have an adjusted OR of 30-day hospital readmission of 2.12 (95% CI 1.17 to 3.83; p=0.013) relative to patients with a discharge RDW ≤13.3%.

Conclusions

In EGS patients requiring critical care who survive hospitalization, an elevated RDW at the time of discharge is a robust predictor of all-cause patient mortality and hospital readmission after discharge.

Level of evidence

Level II, prognostic retrospective study.

Red blood cell distribution width is a survival predictor beyond anemia and Nt-ProBNP in stable optimally medicated heart failure with reduced ejection fraction outpatients

BACKGROUND

RDW is an automatic value obtained with the blood count, and represents the erythrocytes dimension variation.

OBJECTIVE

To evaluate in optimally medicated outpatients with heart failure with reduced ejection fraction (HFrEF) the RDW prognostic value regarding survival in a multivariable model including anemia and Nt-ProBNP.

METHODS

233 consecutive outpatients, LVEF <40%, clinically stable were followed-up for 3-years in an HF Unit. End-point was all-cause death. The RDW categorized according to the tertiles (T1 = <13.9; T2 14-15.2; T3> = 15.3). Anemia classified according to the WHO criteria. Cox survival model adjusted for clinical profile, optimal therapeutic, renal function, Nt-ProBNP, etiology, atrial fibrillation, and anemia.

RESULTS

(1) The 3-years death rate was 33.5%, and increased with the RDW tertiles (17.3%; 25%; 61.1%; p < 0.001). (2) The ROC curve for death associated with RDW (AUC 0.73; p < 0.001); (3) The adjusted death risk increased with the tertiles (Hazard-ratio '[HR] = 1.61; IC 95% 1.09-2.39; p = 0.017). RDW> = 15.3 had greater adjusted death risk than T1 (HR = 2.18; 95% CI 0.99-4.8; p = 0.05) and T1+T2 (HR = 1.54; 95% CI 1.13-2.09; p = 0.006).

CONCLUSION

RDW determined in optimally medicated outpatients with HFrEF, during dry-state, is a strong, cheap, and independent predictor of long-term survival.

Relation between dynamic change of red cell distribution width and 30-day mortality in patients with acute pulmonary embolism

INTRODUCTION AND OBJECTIVES

Recent studies suggest that an increase in red cell distribution width (RDW) levels have a better prognostic value than a single measurement. In the current study, we investigated the predictive value of increasing RDW levels for mortality in acute pulmonary emboli (APE) patients.

MATERIALS AND METHODS

For the study, 199 APE patients who were hospitalized were enrolled. Patients were divided into three groups according to their admission and 24th hour RDW values. Patients for whom both RDW values normal were put in group 1 (normal); patients with admission RDW > 14.5% and decreased 24th hour RDW values were in group 2 (decreased); patients whose 24th hour RDW levels were >14.5% and increased compared to their baseline RDW measurement were in group 3 (increased). Clinical and laboratory findings and 30-day mortality of these groups were compared.

RESULTS

Mean patient age was 68 ± 16, and 48% of the patients were male. There were 98 patients (49%) in group 1, 59 patients (30%) in group 2, and 42 patients (21%) in group 3. Patients in group 3 were older, had lower eGFR and hemoglobin values, and had higher brain type natriuretic peptide values. Mortality rate was higher in group 3 (0%, 3.4%, 19%, respectively, P < .0001). Increase in RDW was independently related to mortality [HR: 4.9, (95%CI: 1.2-18, P = .02)].

CONCLUSION

APE patients with increasing RDW levels have higher mortality rates. Serial measurements of RDW may help us determine patients with high risk for mortality.

Usefulness of admission red blood cell distribution width as a predictor of severity of acute pulmonary embolism

BACKGROUND

Previous researches have represented a considerable relation between acute pulmonary embolism (PE) and red blood cell distribution width (RDW). To the authors' knowledge no research has been informed in subjects with PE severity. Pulmonary arterial obstruction index (PAOI) is associated with the severity of acute PE.

OBJECTIVES

In our investigation, we purposed to assess the relation between PAOI and RDW and the benefit of these factors in the detection of PE severity.

METHODS

We retrospectively investigated the demographic information, probability of clinical scores, laboratory parameters, serum D-dimer levels, and echocardiographic findings of systolic pulmonary artery pressure (PAP) in Acute PE individuals who were diagnosed by computed tomography of pulmonary arterial angiography. Right ventricular dysfunction (RVD) on CT was assessed by calculating the right ventricular/left ventricular (RV/LV) diameter ratios on transverse (RV/LVtrans).

RESULTS

The information of 131 patients with acute PE and 51 (64.6%) female and 28 (35.4%) male healthy control were evaluated. Acute PE group's RDW values were higher than control subjects (P < .0001). RDW (%) level was remarkable higher in patients with massive PE than in patients with nonmassive PE. There were statistically considerable differences in terms of PAOI and systolic pulmonary arterial pressure (sPAP) between nonmassive and massive PE patients (P < .0001 for all).

CONCLUSIONS

PAOI was correlated with PE severity, D-dimer level, sPAP and clinical probability scores. PAOI was correlated with RDW levels. RDW levels, an inexpensive and easily measurable laboratory factor, were considerable associated with the severity and presence of PE.

Red Cell Distribution Width Has a Predictable Value for Differentiation of Provoked and Unprovoked Venous Thromboembolism

Venous thromboembolism (VTE) is generally classified as provoked or unprovoked. This dichotomy is important for following patients, mortality rate, prognosis and whether more efficient therapy is needed. In VTE patients, during initial diagnosis, it is not known exactly whether red cell distribution width (RDW) have a predictable value for this differentiation and pathogenesis. In this study, 298 patients with VTE and 197 control subjects were included. Patients with VTE were defined as provoked or unprovoked with respect to physical examination findings and laboratory values. Changes in RDW were tested between VTE patients and control subjects, provoked and unprovoked VTE patients, and separately with control subjects. RDW was found to be high in provoked and unprovoked groups compared with control group (p < 0.001, p = 0.003 respectively). RDW was significantly high in provoked VTE patients group compared with unprovoked patients (p < 0.001) and a cut-off value was found to be 13.6 %. In ROC analysis, sensitivity was 90.19 % and specificity was 82 % (95 % CI 85.4-93. 8 % and 95 % CI 72.3-89. 6 % respectively). RDW could be used as a simple, costeffective and a reliable test independent of age in differentiation of provoked and unprovoked VTE. In order to better understand its role, prospective large homogenized population studies in different regions are necessary.

Red Blood Cell Distribution Width, Hematology, and Serum Biochemistry in Dogs with Echocardiographically Estimated Precapillary and Postcapillary Pulmonary Arterial Hypertension

Background

Red blood cell distribution width (RDW) is a quantitative measurement of anisocytosis. RDW has prognostic value in humans with different cardiovascular and systemic disorders, but few studies have investigated this biomarker in dogs.

Objectives

To compare the RDW in dogs with precapillary and postcapillary pulmonary hypertension (PH) and a control population of dogs and to correlate RDW with demographic, echocardiographic, and laboratory variables.

Animals

One hundred and twenty‐seven client‐owned dogs including 19 healthy dogs, 82 dogs with myxomatous mitral valve disease (50 dogs without PH and 32 dogs with postcapillary PH), and 26 dogs with precapillary PH.

Methods

Prospective study. Dogs were allocated to groups according to clinical and echocardiographic evaluation. RDW and selected laboratory and echocardiographic variables were compared among dog groups. Associations between RDW and demographic, laboratory, and echocardiographic variables were analyzed using correlation and multiple regression analysis.

Results

Median RDW in dogs with precapillary PH (13.8%, interquartile range 13.2–14.9%) and postcapillary PH (13.7, 13.2–14.7%) was significantly increased compared to healthy dogs (13.3, 12.3–13.7%; P < .05 for both comparisons), but only dogs with severe PH had significantly increased RDW compared to dogs without PH (P < .05). Peak tricuspid regurgitation pressure gradient was significantly associated with increased RDW (rho = 0.263, P = .007). Serum urea concentration, hematocrit, age, and white blood cell number were significantly associated with RDW in the multivariate analysis.

Conclusions and Clinical Importance

Underlying pathophysiologic processes associated with PH instead of severity of PH are likely responsible for increased RDW in dogs with PH.

Diagnostic validity of hematologic parameters in evaluation of massive pulmonary embolism

BACKGROUND

The aim of this study was to determine the hematologic parameter with the highest diagnostic differentiation in the identification of massive acute pulmonary embolism (APE).

METHODS

A retrospective study was performed on patients diagnosing with APE between June 2014 and June 2016. All radiological and laboratory parameters of patients were scanned through the electronic information management system of the hospital. PLR was obtained from the ratio of platelet count to lymphocyte count, NLR was obtained from the ratio of neutrophil count to lymphocyte count, WMR was obtained from white blood cell in mean platelet volume ratio, MPR was obtained from the ratio of mean platelet volume to platelet count, and RPR was obtained from the ratio of red distribution width to platelet count.

RESULTS

Six hundred and thirty-nine patients consisting of 292 males (45.7%) and 347 females (54.3%) were included in the research. Independent predictors of massive risk as compared to sub-massive group were; pulmonary arterial systolic pressure (PASP) (OR=1.40; P=.001), PLR (OR=1.59; P<.001), NLR (OR=2.22; P<.001), WMR (OR=1.22; P<.001), MPR (OR=0.33; P<.001), and RPR (OR=0.68; P<.001). Upon evaluation of the diagnostic differentiation of these risk factors for massive APE by employing receiver operating characteristic curve analysis, it was determined that PLR (AUC±SE=0.877±0.015; P<.001), and NLR (AUC±SE=0.893±0.013; P<.001) have similar diagnostic differentiation in diagnosing massive APE and these two parameters are superior over PASP, MPR, WMR, and RPR.

CONCLUSION

We determined that the levels of NLR and PLR are superior to other parameters in the determination of clinical severity in APE cases.

Red cell distribution width in predicting 30-day mortality in patients with pulmonary embolism

PURPOSE

The aim of the study was to investigate red cell distribution width (RDW) in predicting 30-day mortality in patients with pulmonary embolism (PE).

METHODS

A single-center, retrospective study design was used between January 1, 2014, and February 1, 2016. The primary end point was 30-day mortality after admission. The RDW predicting value was assessed by receiver operating characteristic curves and area under the curve.

RESULTS

A total of 309 patients with PE were included. The 30-day mortality was 14.9% (46/309). The mean RDW level was 13.9%±0.6% (range, 10.7%-21.9%) at admission. The 30-day mortality was higher in the high-RDW-level group compared with the normal-RDW-level group (12.5% vs 23.5%, χ²=5.140, P=.023), with an odds ratio of 2.164 (95% confidence interval [CI], 1.019-4.450). Logistic regression showed that presence of shock, RDW level, and simplified pulmonary embolism severity index (sPESI) were independent risk factors for 30-day mortality in patients with PE. After adjustment by these risk factors, the adjusted odds ratio was 1.439 (95% CI, 1.024-2.116). The area under the curve for RDW predicting the 30-day mortality was 0.6646 (95% CI, 0.5585-0.7518). The cutoff was 16%. The Youden index for RDW and sPESI was 0.400 and 0.453, respectively. When adding RDW into sPESI, the modified sPESI showed highest prediction accuracy, with Youden index 0.499.

CONCLUSIONS

Our results suggested that the RDW is a simple and useful indicator in predicting 30-day mortality in patients with PE. However, this conclusion showed be confirmed by prospective study with large sample.

The accuracy of combined use of troponin and red cell distribution width in predicting mortality of patients with acute pulmonary embolism

BACKGROUND

Cardiac troponins and red cell distribution width (RDW) are associated with increased mortality in acute pulmonary embolism (PE). In this study, we aimed to investigate the accuracy of the combined use of troponin and RDW in predicting short-term mortality in acute PE patients.

METHODS

The data of 201 patients with the diagnosis of acute PE were retrospectively analyzed. We obtained troponin-RDW scores (TR scores) using a combination of troponin and RDW values, and then evaluated this score's accuracy in predicting mortality in patients with acute PE.

RESULTS

The mean participant age was 68 ± 16 years, and 52 % of patients were female. Fifteen (7.4 %) patients died during the first month. Patients classified as high-risk according to TR scores were older (72 ± 15 vs. 66 ± 15 years, p = 0.005), and they had higher heart rates (101 ± 20 vs. 90 ± 15 beat/min, p < 0.001) and respiratory rates (23 ± 4 vs. 21 ± 3 breath/min, p = 0.001). In multivariate analysis, TR (odds ratio [OR] 4.93, 95 % confidence interval [CI] 1.13-21.38, p = 0.033) and simplified pulmonary embolism severity index (sPESI) scores (OR 3.78, 95 % CI 1.71-8.37, p = 0.002) were independent predictors of 30-day mortality. For 30-day mortality, the TR score had a slightly lower sensitivity (87 % vs. 93 %), but a higher specificity (69 % vs. 52 %) compared to the sPESI score.

CONCLUSION

The TR score is easy to calculate, and it may be used to predict early mortality in patients with acute PE.

Mean platelet volume and mean platelet volume/platelet count ratio in risk stratification of pulmonary embolism

BACKGROUND AND OBJECTIVE

Recently, some of the hemogram parameters were reported to predict early death in acute pulmonary embolism (PE). The aim of this study was to investigate the role of mean platelet volume (MPV) and MPV/platelet count ratio (MPV/P), WBC and red cell distribution width (RDW) in risk stratification of patients with acute PE.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of patients with acute PE admitted to the Emergency Department. In addition to the clinical evaluation, the hemogram parameters were measured on admission.

RESULTS

A total of 152 patients were included. Patients with RV dysfunction had significantly higher MPV levels and MPV/P than patients without RV dysfunction. Receiver operating characteristic curve analysis revealed that a MPV cut-off of 7.85fL provided a sensitivity of 53.3% and a specificity of 68.5%, and a MPV/P cut-off of 0.0339fL/(10(9)/L) provided a sensitivity of 69.6% and a specificity of 65% for the prediction of RV dysfunction. There was a positive correlation between MPV and systolic pulmonary artery pressure (SPAP) and between MPV and RV diameter. There was a positive correlation between MPV/P and SPAP and between MPV/P and RV diameter. The low-risk PE group had lower MPV and MPV/P than the massive PE and submassive PE groups.

CONCLUSIONS

MPV and MPV/P were found to be associated with RV dysfunction and clinical severity in acute PE. Low MPV and MPV/P levels may be an indicator of low risk and, high WBC levels may be an indicator of high risk in patients with acute PE. RDW levels may not reflect severity of acute PE.

Red cell distribution width and early mortality in elderly patients with severe sepsis and septic shock

Objective

To investigate the association of red cell distribution width (RDW) with 30-day mortality in elderly patients with severe sepsis and septic shock.

Methods

Patients were recruited from a single tertiary emergency department. Patients with age over 65 years were selected. The main outcome was 30-day mortality. Potential confounders as Acute Physiologic and Chronic Health Evaluation (APACHE) II score and Sequential Organ Failure Assessment (SOFA) score along with initial vital signs were collected. Multivariate Cox proportional hazards analysis was performed to identify independent predictors of 30-day mortality. The discriminative ability of RDW for 30-day mortality was evaluated using receiver operating characteristic curve analysis.

Results

Overall, 458 patients were included. Univariate analysis showed that patients’ survival was significantly associated with sites of infection, comorbidities, and severity scores. In the multivariate Cox proportional hazard model, the RDW was an independent predictor of 30-day mortality (hazards ratio, 1.10; 95% confidence interval, 1.04 to 1.17; P<0.001).

Conclusion

In this study, initial RDW values were significantly associated with 30-day mortality in older patients hospitalized with severe sepsis and septic shock.

Assessments of the associations of thrombus localization with accompanying disorders, risk factors, D-dimer levels, and the red cell distribution width in pulmonary embolism

OBJECTIVE

Pulmonary embolisms occur as a wide spectrum ranging from clinically asymptomatic thrombi to massive thrombi that lead to cardiogenic shock. The purpose of this study was to determine the associations of thrombus localization with risk factors, accompanying disorders, D-dimer levels and the red blood cell distribution width in patients with pulmonary embolism.

MATERIAL AND METHODS

In 148 patients diagnosed with pulmonary embolism, the presence and anatomical localization of the thrombus were assessed via computed tomographic pulmonary angiography. The accompanying disorders, risk factors, serum D-dimer levels, and red blood cell distribution width of the patients were retrospectively evaluated. ClinicalTrials.gov: NCT02388841.

RESULTS

The mean age of the patients was 54±16.0 years, and 48 patients were ≥65 years of age. The most frequent accompanying disorders were chronic obstructive pulmonary disease (22%) and malignancy (10.1%), and the most frequent risk factors were recent operation (14.1%) and immobilization (18.2%). Thrombi were most frequently observed in the right pulmonary artery (37.8%). In 31% of the patients, the thrombus was localized to the main pulmonary arteries. Immobile patients exhibited a higher proportion of thrombi in the main pulmonary arteries than mobile patients. The mean D-dimer level and the mean red blood cell distribution width in the patients with thrombi in the main pulmonary arteries were higher than those in the patients with thrombi in more distal pulmonary arterial branches.

CONCLUSION

Significant associations of proximally localized thrombi with immobilization, the D-dimer levels, and the red blood cell distribution width were observed.

Neutrophil-to-lymphocyte ratio in chronic obstructive pulmonary disease: a retrospective study

Chronic obstructive pulmonary disease (COPD) is a common chronic inflammatory disease of the lung with a high mortality and morbidity rate. Some of the inflammatory markers such as C-reactive protein (CRP), leukocyte count are associated with COPD. In this study, we aimed to evaluate the role of neutrophil-to-lymphocyte ratio (NLR) in COPD patients comparing with the other well-known inflammatory markers. We retrospectively enrolled the laboratory results of 269 COPD patients of which 178 patients at stable period and 91 patients during acute exacerbation and 50 sex- and age- matched healthy controls. We found that NLR values of the stable COPD patients were significantly higher than those of the controls (P < 0.001). During acute exacerbation of the disease there was a further increase compared to stable period (P < 0.001). NLR values were also positively correlated with serum CRP levels and red cell distribution width (RDW) and negatively correlated with mean platelet volume (MPV) in both COPD groups. In conclusion, NLR could be considered as a new inflammatory marker for assessment of inflammation in COPD patients with its quick, cheap, easily measurable property with routine complete blood count analysis.

Red blood cell distribution width in patients with cryptogenic stroke

BACKGROUND

There is no information about a possible association of red blood cell distribution width (RDW) with cryptogenic stroke (CS). We aimed to analyze the association of RDW with CS.

PATIENTS AND METHODS

One hundred and sixty-three patients with CS were included along with 186 healthy controls. Fibrinogen, leukocytes, hemoglobin, and erythrocyte indices were evaluated.

RESULTS

Patients showed higher RDW, leukocyte count, and body mass index (BMI) than controls (P < .05). No differences were observed in the erythrocyte indices or in glucose, cholesterol, and triglycerides levels (P > .05). When patients with anemia were excluded from the study (6 controls and 5 cases), the differences between cases and controls persisted (P = .005). Multivariate logistic regression revealed that, after adjusting for potential confounders (anemia, age > 40 years, gender, and fibrinogen >382 mg/dL, total cholesterol >240 mg/dL, and BMI > 28.7 kg/m(2)), RDW >14% was the only parameter that independently increased the risk of CS.

CONCLUSION

The RDW >14% increased the risk of CS by 2.5-fold, irrespectively of anemia, inflammation, and lipidic profile.

Prognostic value of red blood cell distribution width for patients with heart failure: a systematic review and meta-analysis of cohort studies

Aims

Multiple studies have investigated the prognostic role of red blood cell distribution width (RDW) for patients with heart failure (HF), but the results have been inconsistent. The aim of the present study was to estimate the impact of RDW on the prognosis of HF by performing a systematic review and meta-analysis.

Methods and Results

The Embase, PubMed, and Web of Science databases were searched up to November 16, 2013 to identify eligible cohort studies. The quality of each study was assessed using the Newcastle-Ottawa Scale (NOS). The association between RDW, either on admission or at discharge, and HF outcomes (all-cause mortality [ACM], heart transplantation, cardiovascular mortality, and rehospitalization, etc.) were reviewed. The overall hazard ratio (HR) for the effect of RDW on ACM was pooled using a random-effects model, and the publication bias was evaluated using funnel plots and Eggers' tests. Seventeen studies, with a total of 18288 HF patients, were included for systematic review. All eligible studies indicated that RDW on admission and RDW at discharge, as well as its change during treatment, were of prognostic significance for HF patients. The HR for the effect of a 1% increase in baseline RDW on ACM was 1.10 (95% confidence interval: 1.07–1.13), based on pooling of nine studies that provided related data. However, publication bias was observed among these studies.

Conclusions

HF patients with higher RDW may have poorer prognosis than those with lower RDW. Further studies are needed to explore the potential mechanisms underlying this association.

Red cell distribution width is increased in chronic thromboembolic pulmonary hypertension

INTRODUCTION

Chronic thromboembolic pulmonary hypertension (CTEPH) is a life-threatening condition characterized by single or recurrent pulmonary embolisms, which promotes pulmonary vascular remodeling. There is significant relationship between red cell distribution width (RDW) and pulmonary hypertension; however, the usefulness of RDW as biomarker for the diagnosis of CTEPH remains poorly defined.

OBJECTIVE

This study sought to assess the change and the diagnostic value of RDW in CTEPH.

METHODS

This retrospective study included 56 CTEPH patients and 56 sex- and age-matched healthy controls treated at Beijing Chao-Yang Hospital. Correlations between RDW and hematological and hemodynamic parameters were assessed. A logistic regression model was applied to test independent parameters in relation to the diagnosis of CTEPH, and receiver operating characteristic curve was plotted to determine the diagnostic value of RDW in CTEPH.

RESULTS

RDW values were significantly higher in CTEPH patients (13.82% ± 1.14%) compared with healthy controls (12.75% ± 0.49%) and in World Health Organization (WHO), functional class III-IV cases (14.39% ± 1.24%) compared with class I-II cases (13.32% ± 0.78%) (both P = 0.000). RDW levels in CTEPH patients showed negative correlations with hemoglobin (r = -0.357, P = 0.007) and cardiac index (r = -0.288, P = 0.031), and positive correlations with pulmonary vascular resistance (r = 0.292, P = 0.029) and WHO functional class (r = 0.450, P = 0.001). Moreover, RDW was an independent parameter in the diagnosis of CTEPH (95% confidence interval: 2.866-13.698, P = 0.000); in particular, an RDW level ≥ 13.05% was the most useful cut-off value, with a sensitivity of 82.1% and a specificity of 71.4%.

CONCLUSION

Increased RDW level may be an acceptable diagnostic parameter for CTEPH.

Prognostic value of red cell distribution width in patients with sarcoidosis

BACKGROUND

Sarcoidosis is a multisystem granulomatous disorder of unknown etiology. There are no data on the indications for specific tests or optimal frequency for monitoring of the disease activity in sarcoidosis.

METHODS

Complete blood counts, demographics and pulmonary function data from sarcoidosis patients evaluated between 2006 and 2012 were collated retrospectively. During follow-up, the latest red cell distribution width (RDW) values of the patients were recorded. The prognosis and diagnosis of sarcoidosis was based on according to the guideline. Sarcoidosis progression was classified as follows: remission, stable disease and progreesive disease.

RESULTS

The diagnosis was based on histopathological findings in 93 out of 138 (67.4%) patients. In our cohort, the baseline mean RDW levels were 14.1% ± 1.2. The RDW distribution by stage was as follows: stage I: 14.0% (± 1.6), II: 14.2% (± 1.5), III: 13.8% (± 0.9) and IV: 15.8% (± 2.0). In patients with stage IV, baseline and follow-up values of RDW were found to be significantly higher than the other stages. While the mean baseline RDW was 14.8 (± 1.4) in the progressive disease, upon follow-up, the mean RDW had increased to 16.5% (± 1.4) (P = 0.021), No difference was found between the baseline and follow-up levels of RDW in the regressive and stable groups.

CONCLUSIONS

Serial RDW levels may be beneficial marker to predict progression of sarcoidosis.

Red cell distribution width is associated with long-term prognosis in patients with stable coronary artery disease

Background

Data regarding the association between red cell distribution width (RDW) values and mortality in patients with stable coronary artery disease are scarce. We aimed to investigate the link between mortality and RDW in patients with stable coronary artery disease undergoing percutaneous coronary intervention (PCI).

Methods

We analyzed 2550 consecutive patients with stable coronary artery disease who underwent PCI between 2007 and 2011 at our institution. The patients were divided into four groups according to RDW quartiles. The association between the RDW values and the outcomes was assessed using Cox proportional regression analysis after adjusting for clinical, echocardiographic, hemodynamic and laboratory data in the whole population and in subgroups stratified by gender, presence of diabetes, anemia or heart failure.

Results

In the entire population, there was a stepwise relationship between RDW intervals and comorbidities. Patients with the highest RDW values were older and more often burdened with diabetes, heart failure and chronic kidney disease. There was an almost 4-fold increase in mortality during an average of 2.5 years of follow-up between the group of patients with RDW values lower than 13.1% (25^th percentile) and the group with RDW values higher than 14.1% (75^th percentile), (4.3% vs. 17.1%, p < 0.0001). After adjusting for the covariates, RDW remained significantly associated with mortality in the whole cohort (HR-1.23 [95% CI (1.13-1.35), p < 0.0001]) and in the subgroups stratified by gender, age (over and under 75 years), presence of anemia, diabetes, heart failure and chronic kidney disease.

Conclusion

Higher RDW values correspond to higher comorbidity burdens and higher mortality. RDW is an independent predictor of mortality in patients with stable coronary artery disease.

Quantitative trait locus linkage analysis in a large Amish pedigree identifies novel candidate loci for erythrocyte traits

We characterized a large Amish pedigree and, in 384 pedigree members, analyzed the genetic variance components with covariate screen as well as genome-wide quantitative trait locus (QTL) linkage analysis of red blood cell count (RBC), hemoglobin (HB), hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), red cell distribution width (RDW), platelet count (PLT), and white blood cell count (WBC) using SOLAR. Age and gender were found to be significant covariates in many CBC traits. We obtained significant heritability estimates for RBC, MCV, MCH, MCHC, RDW, PLT, and WBC. We report four candidate loci with Logarithm of the odds (LOD) scores above 2.0: 6q25 (MCH), 9q33 (WBC), 10p12 (RDW), and 20q13 (MCV). We also report eleven candidate loci with LOD scores between 1.5 and <2.0. Bivariate linkage analysis of MCV and MCH on chromosome 20 resulted in a higher maximum LOD score of 3.14. Linkage signals on chromosomes 4q28, 6p22, 6q25, and 20q13 are concomitant with previously reported QTL. All other linkage signals reported herein represent novel evidence of candidate QTL. Interestingly rs1800562, the most common causal variant of hereditary hemochromatosis in HFE (6p22) was associated with MCH and MCHC in this family. Linkage studies like the one presented here will allow investigators to focus the search for rare variants amidst the noise encountered in the large amounts of data generated by whole-genome sequencing.