Persistent increase in red cell size distribution width after acute diseases: A biomarker of hypoxemia?

Red Blood Cell Distribution Width is a Biomarker of Red Cell Dysfunction Associated with High Systemic Inflammation and a Prognostic Marker in Heart Failure and Cardiovascular Disease: A Potential Predictor of Atrial Fibrillation Recurrence

At the beginning of the 21st century, approximately 2.3 million US adults had atrial fibrillation (AF), and there has been a 60% increase in hospital admissions for AF. Given that the expectancy is a continuous increase in incidence, it portends a severe healthcare problem. Considerable evidence supports the immune system and inflammatory response in cardiac tissue, and circulatory processes are involved in the physiopathology of AF. In this regard, finding novel inflammatory biomarkers that predict AF recurrence after catheter ablation (CA) is a prime importance global healthcare problem. Many inflammatory biomarkers and natriuretic peptides came out and were shown to have predictive capabilities for AF recurrence in patients undergoing CA. In this regard, some studies have shown that red blood cell distribution width (RDW) is associated with the risk of incident AF. This review aimed to provide an update on the evidence of the RDW as a biomarker of red cell dysfunction and its association with high systemic inflammation, and with the risk of incident AF. Through the literature review, we will highlight the most relevant studies of the RDW related to AF recurrence after CA. Many studies demonstrated that RDW is associated with all cause-mortality, heart failure, cardiovascular disease, and AF, probably because RDW is a biomarker of red blood cell dysfunction associated with high systemic inflammation, reflecting an advanced heart disease with prognostic implications in heart failure and cardiovascular disease. Thus, suggesting that could be a potential predictor for AF recurrence after CA. Moreover, the RDW is a parameter included in routine full blood count, which is low-cost, quick, and easy to obtain. We provided an update on the evidence of the most relevant studies of the RDW related to AF recurrence after CA, as well as the mechanism of the high RDW and its association with high systemic inflammation and prognostic marker in cardiovascular disease and heart failure.

Application of neutrophil-lymphocyte ratio and red blood cell distribution width in diabetes mellitus complicated with heart failure

BACKGROUND

Accumulating clinical evidence has shown that diabetes mellitus (DM) is a serious risk factor for cardiovascular disorders and an important factor for adverse cardiovascular events.

AIM

To explore the value of the combined determination of the neutrophil-lymphocyte ratio (NLR) and red blood cell distribution width (RDW) in the early diagnosis and prognosis evaluation of DM complicated with heart failure (HF).

METHODS

We retrospectively analyzed clinical data on 65 patients with type 2 DM (T2DM) complicated with HF (research group, Res) and 60 concurrent patients with uncomplicated T2DM (control group, Con) diagnosed at Zhejiang Provincial People's Hospital between January 2019 and December 2021. The NLR and RDW values were determined and comparatively analyzed, and their levels in T2DM + HF patients with different cardiac function grades were recorded. The receiver operating characteristic (ROC) curves were plotted to determine the NLR and RDW values (alone and in combination) for the early diagnosis of HF. The correlation between NLR and RDW with the presence or absence of cardiac events was also investigated.

RESULTS

Higher NLR and RDW levels were identified in the Res vs the Con groups (P < 0.05). The NLR and RDW increased gradually and synchronously with the deterioration of cardiac function in the Res group, with marked differences in their levels among patients with grade II, III, and IV HF (P < 0.05). ROC curve analysis revealed that NLR combined with RDW detection had an area under the curve of 0.915, a sensitivity of 76.9%, and a specificity of 100% for the early diagnosis of HF. Furthermore, HF patients with cardiac events showed higher NLR and RDW values compared with HF patients without cardiac events.

CONCLUSION

NLR and RDW were useful laboratory indicators for the early diagnosis of DM complicated with HF, and their joint detection was beneficial for improving diagnostic efficiency. Additionally, NLR and RDW values were directly proportional to patient outcomes.

Evaluation of CSF 8-iso-prostaglandin F2α and erythrocyte anisocytosis as prognostic biomarkers for delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage

Delayed cerebral ischemia (DCI) is a serious, life-threatening, complication affecting patients who have survived the initial bleeding from a ruptured intracranial aneurysm. Due to the challenging diagnosis, potential DCI prognostic markers should be of value in clinical practice. According to recent reports isoprostanes and red blood cell distribution (RDW) showed to be promising in this respect. We conducted a prospective study of 27 aSAH patients and control group (n = 8). All patients from the study group were treated within the first day of the initial bleeding. We collected data regarding clinical status and results of biochemical, and radiological examinations. We measured cerebrospinal fluid (CSF) concentration of 8-iso-prostaglandin F2α (F2-IsoP) and RDW on days 1, 3, and 5. Both CSF F2-IsoP level and RDW-SD measured on day 1 were significant predictors of DCI. The receiver operating characteristics curve for DCI prediction based on the multivariate model yielded an area under the curve of 0.924 (95% CI 0.824-1.000, p < 0.001). In our study, the model based on the combination of RDW and the level of isoprostanes in CSF on the first day after the initial bleeding showed a prognostic value for DCI prediction. Further studies are required to validate this observation.

Association between red blood cell distribution width and all-cause mortality of patients after intra-aortic balloon pump in the intensive care unit

Objectives

This study aimed to explore the relationship between red blood cell distribution width (RDW) and all-cause mortality in critically ill patients undergoing intra-aortic balloon pumping (IABP) in the intensive care unit (ICU).

Methods

This study retrospectively analyzed data from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. The primary endpoint was the 30-day mortality rate, while the secondary endpoint was the in-hospital mortality rate. Restricted cubic splines were used to assess the dose-response relationship. The receiver operating characteristic (ROC) curve and Kaplan-Meier curve analysis were carried out to evaluate the predictive performance of RDW. Moreover, multiple logistic regression analyses and subgroup analyses were conducted to investigate the relationship between RDW and 30-day mortality. Finally, propensity score matching (PSM) was performed to adjust for the imbalance of covariates.

Results

In total, 732 patients were finally identified from the MIMIC-IV database in this study. The RDW of patients in the non-survivor group was significantly higher compared with those in the survivor group (P < 0.01). Multiple logistic regression analyses corroborated RDW was an independent predictor of all-cause 30-day mortality in critically ill patients post-IABP. Meanwhile, ROC analysis identified an RDW cutoff of 14.2%. High RDW patients exhibited a 131% (OR = 2.31, 95% CI: 1.49-3.61) elevated risk of 30-day mortality after adjusting for confounders in multivariable logistic regression. After PSM, 412 patients were included in the matched cohort. In the original and matched cohorts, the high RDW group had higher 30-day and in-hospital mortality rates, as well as longer ICU stays. Lastly, the area under the ROC curve for 30-day mortality was 0.686, with an optimal cutoff point of 14.2 for RDW (sensitivity: 69.09 % and specificity: 63.32%).

Conclusion

RDW could be a simple and valuable prognostic tool to predict mortality in critically ill patients after IABP.

Association of Red Cell Distribution Width and Mean Platelet Volume With Disease Activity in Rheumatoid Arthritis Patients

BACKGROUND

The inner layer of the synovial joints is the primary target of rheumatoid arthritis, or RA, a chronic systemic inflammatory disorder that is linked to increasing disability, early mortality, and economic hardships. The objective is to determine the association of red cell distribution width (RDW) and mean platelet volume (MPV) with disease activity in RA.

MATERIAL AND METHODS

A retrospective study was conducted between July 2021 and January 2022 in the outpatient rheumatology clinics at Gulab Devi Teaching Hospital. In this study, 100 consecutive participants with a diagnosis of RA fulfilling the ACR/EULAR 2010 classification criteria were enrolled. Patient's records were reviewed for age, gender, length of illness, smoking status, treatment history, current treatment regimen, concomitant medications, rheumatoid factor (RF), anti-cyclic citrulline peptide (anti-CCP) antibodies, and extra-articular manifestations. Laboratory investigations were reviewed for complete blood count including RDW and MPV, ESR, CRP, liver, and renal functions. Disease activity score DAS 28-ESR was used to quantify disease activity. To determine the relationship between different parameters and the RDW and MPV, linear regression research was conducted.

RESULTS

According to the DAS28 score, 12% of patients were in remission, 9% had low, 34% had moderate, and 45% had high disease activity. DAS28 score was 5.01±1.72 (2.45-9.32) and RDW was 16.18±4.42. There was a strong positive correlation (r = 0.653) of RDW with the DAS28 score and it was statistically significant (p<0.001). MPV was 11.30±2.09 fL. There was a moderately positive correlation (r = 0.366) of MPV with the DAS28 score and it was statistically significant (p<0.001).

CONCLUSION

Conclusively, both RDW and MPV are positively related to disease activity in patients with RA. These can be used as a simple tool for assessing disease activity and guiding the treatment.

Association of red cell distribution width and its changes with the 30-day mortality in patients with acute respiratory failure: An analysis of MIMIC-IV database

BACKGROUND

Acute respiratory failure (ARF) is a common disease in the intensive care units (ICUs) with high risk of mortality. The red cell distribution width (RDW) is one of baseline ICU indicators which can be easily available, and has been used in the long-term prognostic analyses of diseases. However, no studies have explored the role of baseline RDW and its change during hospitalization in in-hospital mortality in ARF. Herein, this study aims to explore the association between RDW and its changes and the 30-day mortality in ARF patients.

METHODS

Demographic and clinical data of 7,497 patients with ARF were extracted from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database in 2012-2019 in this retrospective cohort study. Univariable and multivariable Cox regression analyses were used to explore the association between RDW and its changes and 30-day mortality with hazard ratios (HRs) and 95% confidence intervals (CIs). Subgroup analyses of different baseline RDW levels were also performed. We then assessed the predictive performance of RDW changes combined with the Sequential Organ Failure Assessment (SOFA) score on 30-day mortality using receiver operator characteristic curves (ROCs) with areas under curve (AUCs).

RESULTS

Totally, 2,254 (30.07%) patients died in 30 days. After adjusting for covariates, we found that high baseline RDW [HR = 1.25, 95%CI: (1.15-1.37)] and RDW changes ≥0.3% [HR = 1.12, 95%CI: (1.01-1.24)] were both related to an increased risk of 30-day mortality. In patients whose baseline RDW level ≥14.9%, RDW changes ≥0.3% was also associated with an increased risk of 30-day mortality [HR = 1.19, 95%CI: (1.05-1.35)]. Moreover, the predictive value of RDW changes combined with SOFA on 30-day mortality was a little better than that of single SOFA score, with AUCs of 0.624 vs. 0.620.

CONCLUSION

High baseline RDW level and its changes during hospitalization was relate to the increased risk of 30-day mortality in ARF, and the predictive value of RDW changes for ARF short-term mortality is still needed exploration.

Predictive nomogram for in-hospital mortality among older patients with intra-abdominal sepsis incorporating skeletal muscle mass

BACKGROUND

Studies on prognostic factors for older patients with intra-abdominal sepsis are scarce, and the association between skeletal muscle mass and prognosis among such patients remains unclear.

AIMS

To develop a nomogram to predict in-hospital mortality among older patients with intra-abdominal sepsis.

METHODS

Older patients with intra-abdominal sepsis were prospectively recruited. Their demographics, clinical features, laboratory results, abdominal computed tomography-derived muscle mass, and in-hospital mortality were recorded. The predictors of mortality were selected via least absolute shrinkage and selection operator and multivariable logistic regression analyses, and a nomogram was developed. The nomogram was assessed and compared with Sequential Organ Failure Assessment score, Acute Physiology and Chronic Health Evaluation II score, and Simplified Acute Physiology Score II.

RESULTS

In total, 464 patients were included, of whom 104 (22.4%) died. Six independent risk factors (skeletal muscle index, cognitive impairment, frailty, heart rate, red blood cell distribution width, and blood urea nitrogen) were incorporated into the nomogram. The Hosmer-Lemeshow goodness-of-fit test and calibration plot revealed a good consistency between the predicted and observed probabilities. The area under the receiver operating characteristic curve was 0.875 (95% confidence interval = 0.838-0.912), which was significantly higher than those of commonly used scoring systems. The decision curve analysis indicated the nomogram had good predictive performance.

DISCUSSION

Our nomogram, which is predictive of in-hospital mortality among older patients with intra-abdominal sepsis, incorporates muscle mass, a factor that warrants consideration by clinicians. The model has a high prognostic ability and might be applied in clinical practice after external validation.

Red blood cell distribution width for the prediction of outcomes after cardiac arrest

The red blood cell distribution width (RDW) is a routinely available blood marker that measures the variation of the size/volume of red blood cells. The aim of our study was to investigate the prognostic value of RDW in cardiac arrest patients and to assess whether RDW improves the prognostic value of three cardiac arrest-specific risk scores. Consecutive adult cardiac arrest patients admitted to the ICU of a Swiss university hospital were included. The primary outcome was poor neurological outcome at hospital discharge assessed by Cerebral Performance Category. Of 702 patients admitted to the ICU after cardiac arrest, 400 patients (57.0%) survived, of which 323 (80.8%) had a good neurological outcome. Higher mean RDW values showed an independent association with poor neurological outcomes at hospital discharge (adjusted OR 1.27, 95% CI 1.14 to 1.41; p < 0.001). Adding the maximum RDW value to the OHCA- CAHP- and PROLOGUE cardiac arrest scores improved prognostic performance. Within this cohort of cardiac arrest patients, RDW was an independent outcome predictor and slightly improved three cardiac arrest-specific risk scores. RDW may therefore support clinical decision-making.

Red Cell Distribution Width/Albumin Ratio: A Predictor of In-Hospital All-Cause Mortality in Patients with Acute Myocardial Infarction in the ICU

Purpose

Red cell distribution width (RDW) and albumin level are linked to adverse outcomes in patients with acute myocardial infarction (AMI). Nonetheless, it remains unknown whether the RDW/albumin ratio (RAR) is associated with the short-term prognosis of AMI. Using a large cohort, we aimed to explore the association between RAR and in-hospital all-cause mortality in intensive care unit (ICU) patients with AMI.

Patients and Methods

The patients' data analyzed in this retrospective cohort investigation were obtained from the eICU Collaborative Research Data Resource. RAR was calculated based on the serum albumin level and RDW. The primary outcome was in-hospital all-cause mortality. Receiver operating characteristic curve, multiple logistic regression model, and Kaplan-Meier survival analysis were performed to explore the prognostic value of RAR.

Results

We enrolled 2594 patients in this study. After correcting for confounding factors, the RAR was an independent predictor for in-hospital mortality in our model (odds ratio [OR] 1.27, 95% confidence interval [CI] 1.12, 1.43). A similar relationship was observed with mechanical ventilation use. RAR showed a better predictive value with an area under the curve (AUC) of 0.738 (cutoff, 4.776) for in-hospital all-cause mortality compared to RDW or albumin alone. Kaplan-Meier estimator curve analyses for RAR demonstrated that the group with RAR ≥4.776%/g/dL had poorer survival than the group with RAR <4.776%/g/dL (p< 0.0001). The subgroup analysis revealed no significant interaction between RAR and in-hospital all-cause mortality in all strata.

Conclusion

RAR was an independent risk factor for in-hospital all-cause mortality in ICU patients with AMI. Higher RAR values corresponded to higher mortality rates. RAR is a more accurate predictor of in-hospital all-cause mortality in patients with AMI in the ICU than albumin or RDW. Thus, RAR may be a potential biomarker of AMI.

Parameters and Morphological Changes of Erythrocytes and Platelets of COVID-19 Subjects: A Longitudinal Cohort Study

Purpose

Information about dynamic changes occurring in the parameters and morphology of erythrocytes and platelets during the coronavirus disease 2019 (COVID-19) infection and convalescence is scarce. To explore potential associations between dynamic erythrocyte and platelet parameters, morphological changes, and the course or severity of the disease is essential.

Patients and Methods

From January 17th, 2020, to February 20th, 2022, we followed up on 35 patients with non-severe and 11 patients with severe COVID-19 following their discharge. We collected clinical features, dynamic complete blood count (CBC), and peripheral blood smears (PBS) and analyzed parameter and morphological changes of erythrocytes and platelets depending on the course or severity of the disease. The course of the disease included four periods, namely onset (T1), discharge (T2), 1-year follow-up (T3), and 2-year follow-up (T4).

Results

Red blood cell (RBC) counts and hemoglobin were the lowest in T2, followed by T1, and lower in T1 and T2 than in T3 and T4. Inversely, the red blood cell distribution width (RDW) was the highest in T2, followed by T1, and higher than in T3 and T4. Compared to non-severe patients, the platelet of severe patients was lower in T1 and T2. In contrast, the mean platelet volume (MPV) and platelet distribution width (PDW) tended to be higher in severe patients. Similarly, anisocytosis was more common in peripheral blood smears at early stages and in severe patients. Finally, large platelets were more common in severe patients.

Conclusion

Anisocytosis of erythrocytes and large platelets are found in patients with severe COVID-19, these changes may help primary hospitals to identify patients with a high risk of severe COVID-19 at an early stage.

Relationship between red blood cell distribution width-to-albumin ratio and outcome of septic patients with atrial fibrillation: a retrospective cohort study

BACKGROUND

This retrospective cohort study aimed to investigate the association between red blood cell distribution width-to-albumin ratio (RAR) and in-hospital mortality in patients with sepsis and atrial fibrillation (AF).

METHODS

Data were obtained from the Medical Information Mart for the Intensive Care Database IV database version 1.0. Multivariate Cox regression models, curve-fitting, and Kaplan-Meier analyses were performed to determine the correlation between RAR and in-hospital mortality in patients with sepsis and AF.

RESULTS

This study included 3042 patients with sepsis and AF. Confounding variables were adjusted for in the Multivariable Cox regression analysis models. RAR was independently associated with in-hospital mortality (hazard ratio 1.06; 95% confidence interval 1.03-1.08; p < 0.001). A linear relationship was found between the RAR and in-hospital mortality in patients with sepsis and AF.

CONCLUSION

Elevated RAR levels are associated with increased in-hospital mortality in patients with sepsis and AF. Further research is required to confirm this association.

Red cell distribution width as a prognosticator in patients with heart failure

AIMS

Increased red cell distribution width (RDW) is a poor prognostic factor in patients with heart failure (HF). However, only a few large-scale studies have identified the clinical utility of RDW after adjusting for covariates affecting RDW.

METHODS AND RESULTS

From January 2010 to April 2021, we retrospectively enrolled patients diagnosed with HF from three referral hospitals with available RDW data (taken within 3 months of HF diagnosis) using an integrated clinical data system. Patients with an ejection fraction (EF) < 50% or HFA-PEFF (Heart Failure Association Pre-test assessment, Echocardiography and natriuretic peptide, Functional testing, Final aetiology) score ≥ 2 without severe valvular heart disease or coronary revascularization were enrolled. The primary endpoint was all-cause mortality, and cardiovascular mortality was also collected. Multivariable Cox regression analysis and stabilized inverse probability of treatment weighting (IPTW) were used to identify any association between RDW and all-cause death by balancing covariates or compounding factors. The global χ² score was calculated and discrimination analysis was performed to evaluate the incremental value of RDW in predicting prognosis. Among the 6599 participants enrolled in this study, 1256 (19.0%) cases of all-cause death occurred, and the median duration of follow-up was 887 (interquartile range 351-1589) days. Elevated RDW at the initial diagnosis was associated with poor prognosis [cumulative incidence: 819 (30.2%) vs. 437 (11.2%), relative risk 1.58, 95% confidence interval (CI) 1.51-1.67, log-rank P < 0.001]. Multivariable Cox analysis showed that elevated RDW was a poor prognostic factor for the primary endpoint [hazard ratio (HR) 1.11, 95% CI 1.06-1.16, P < 0.001], independent of clinical risk factors, N-terminal pro-brain natriuretic peptide (NT-proBNP), and EF, which was concordant with the stabilized IPTW (HR 1.29, 95% CI 1.10-1.49, P < 0.001). Adding RDW to model composed of traditional risk factors, NT-proBNP, and echocardiographic parameters showed incremental prognostic value for predicting poor prognosis (area under the receiver operating characteristic curve, 0.799-0.826; P < 0.001).

CONCLUSIONS

Increased RDW at the time of diagnosis is associated with poor prognosis in patients with HF, independent of clinical risk factors, such as NT-proBNP, and echocardiographic parameters. Therefore, RDW may aid in the management of these patients beyond traditional risk factors.

CORRELATION BETWEEN RED BLOOD CELL DISTRIBUTION WIDTH-TO-PLATELET RATIO AND MORTALITY IN PATIENTS WITH ACUTE RESPIRATORY DISTRESS SYNDROME: A RETROSPECTIVE COHORT STUDY

ABSTRACT

Background: This study aims to assess the prognostic value of red blood cell distribution width-to-platelet ratio (RPR) in acute respiratory distress syndrome (ARDS) patients. Methods: The data collected from 540 ARDS patients from 2001 to 2012 were obtained from the Medical Information Mart for Intensive Care III Database. The 28-day all-cause mortality risk was considered as the primary outcome parameter, and the secondary outcomes were 60- and 90-day all-cause mortality. The association between RPR (≥0.19 vs. <0.19) and mortality was assessed by Cox proportional hazards models, and potential nonlinear associations were assessed by restricted cubic spline regression analysis. Results: The 28-day all-cause mortality was 22.4%. Among the 121 deaths, 92 (20.0%) presented with an RPR <0.19, and 29 patients had RPR ≥0.19 ( P < 0.001). The 60- and 90-day all-cause mortality was 27% and 28.7%, respectively. After adjusting for the relevant factors in the multivariate model, RPR ≥0.19 was independently correlated with the 28-day all-cause mortality (hazard ratio, 2.74; 95% confidence interval, 1.46-5.15; P = 0.002). There was no nonlinear relationship between RPR and the risk of 28-day all-cause mortality ( P for overall association <0.001, P for nonlinear = 0.635). Similar results were observed for both the pneumonia and nonpneumonia subgroups and sensitivity analyses. Conclusions: The data promote the use of RPR as a valuable prognostic indicator for ARDS patients.

Association of Red Blood Cell Distribution Width with Stroke Prognosis Among Patients with Small Artery Occlusion: A Hospital-Based Prospective Follow-Up Study

Objective

Stroke is the leading cause of mortality and disability worldwide. However, there is no study on the relationship between red blood cell distribution width and the prognosis of small artery occlusion, which is a stroke subtype. This study aimed to assess the association of red blood cell distribution width at admission with outcomes among patients with small artery occlusion.

Methods

In this hospital-based follow-up study, all included patients were diagnosed with small artery occlusion. Outcomes included death, recurrence, and dependency at 3, 12, and 36 months after stroke onset. Multivariate analysis was performed to explore the association of red blood cell distribution width with stroke outcomes.

Results

This study included 1576 patients with small artery occlusion who were followed up at 3, 12, and 36 months. For every unit increase in red blood cell distribution width, the risk of stroke recurrence and dependency increased by 5.1% (95% CI 1.002–1.102, P=0.039) at 3 months after stroke onset. At the 12-month follow-up, for every unit increase in red blood cell distribution width, the risk of stroke recurrence increased by 3.4% (95% CI 1.000–1.069, P=0.047). However, the relationship between red blood cell distribution width and mortality rate was not significant at 36 months after stroke onset after adjustment of covariates.

Conclusion

Red blood cell distribution width is an important hematological index of small artery occlusion. It may be used to predict the recurrence of acute ischemic stroke in small artery occlusion. Therefore, patients with higher baseline values of red blood cell distribution width may need more risk factor control to reduce recurrence and dependency.

Association Between Red Blood Cell Distribution Width-Albumin Ratio and Hospital Mortality in Chronic Obstructive Pulmonary Disease Patients Admitted to the Intensive Care Unit: A Retrospective Study

Purpose

High levels of red blood cell distribution width (RDW) and hypoalbuminemia are markers of poor prognosis in chronic obstructive pulmonary disease (COPD) patients. However, few studies have shown that the red blood cell distribution width–albumin ratio (RAR) is related to the mortality of COPD. This study aimed to explore the relationship between RAR and hospital mortality in COPD patients admitted to the intensive care unit (ICU).

Patients and Methods

Patients were retrospectively incorporated from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database and divided into two groups by a cutoff value of RAR. Propensity score matching (PSM) was performed to adjust for the imbalance of covariates. Logistic regression models and subgroup analyses were carried out to investigate the relationship between RAR and hospital mortality. The receiver operating characteristic (ROC) curve was used to evaluate the predictive performance of RAR and decision curve analysis (DCA) to assess the clinical utility.

Results

In total, 1174 patients were finally identified from the MIMIC-IV database. The cutoff value for RAR was 5.315%/g/dL. After PSM at a 1:1 ratio, 638 patients were included in the matched cohort. In the original and matched cohorts, the high RAR group had higher hospital mortality and longer hospital stays. Logistic regression analysis suggested that RAR was an independent risk factor for hospital mortality. The areas under the ROC curve in the original and matched cohorts were 0.706 and 0.611, respectively, which were larger than applying RDW alone (the original cohort: 0.600, the matched cohort: 0.514). The DCA indicated that RAR had a clinical utility.

Conclusion

A higher RAR (>5.315%/g/dL) was associated with hospital mortality in COPD patients admitted to ICU. As an easily available peripheral blood marker, RAR can predict hospital mortality in critically ill patients with COPD independently.

Red cell distribution width and mean platelet volume in rheumatoid arthritis patients: Its association with disease activity

INTRODUCTION

Hemogram parameters have been recently proposed as markers of inflammation in various studies from different parts of the world. Two of these hemogram parameters are red cell distribution width (RDW) and mean platelet volume (MPV).

AIM

To evaluate the relation between RDW and MPV with disease activity of rheumatoid arthritis. To assess whether RDW and MPV can be used to follow disease activity in RA patients.

METHODS

This is an observational cross-sectional study that was carried out on 60 rheumatoid arthritis patients who fulfilled the ACR/EULAR2010 classification criteria of RA attending to Rheumatology and Rehabilitation inpatient and outpatient clinics at Zagazig University Hospitals. All cases were subjected to full history taking, clinical examination, and laboratory investigations; differential complete blood picture (CBC), acute phase reactants (CRP and ESR), rheumatoid factor (RF) and anti-cyclic-citrullinated peptide (anti-CCP) antibodies. Disease activity was measured by disease activity score 28 (DAS28).

RESULTS

The cut-off levels of RDW and MPV were 14.85 and 11.25. Patients with RDW>14.85 had higher Disease Activity Score 28 (DAS28; p=0.0003), ESR (p=0.0001) and CRP (p=0.0001). RDW was positively correlated with disease activity markers (ESR, CRP and DAS28) in rheumatoid arthritis patients. But, DAS28 was not different between patients with MPV>11.25 and <11.25.

CONCLUSION

RDW was strongly correlated with disease activity. Also, RDW was better than ESR and CRP in detecting RA disease activity. According to these findings we suggest that RDW can be used in clinics to follow disease activity. In addition, RDW is widely available; as it's usually included in routine complete blood picture and there will be no need for further cost.

Succinate dehydrogenase inversely regulates red cell distribution width and healthy lifespan in chronically hypoxic mice

Increased red cell distribution width (RDW), which measures erythrocyte volume (MCV) variability (anisocytosis), has been linked to early mortality in many diseases and in older adults through unknown mechanisms. Hypoxic stress has been proposed as a potential mechanism. However, experimental models to investigate the link between increased RDW and reduced survival are lacking. Here, we show that lifelong hypobaric hypoxia (~10% O2) increases erythrocyte numbers, hemoglobin and RDW, while reducing longevity in male mice. Compound heterozygous knockout (chKO) mutations in succinate dehydrogenase (Sdh; mitochondrial complex II) genes Sdhb, Sdhc and Sdhd reduce Sdh subunit protein levels, RDW, and increase healthy lifespan compared to wild-type (WT) mice in chronic hypoxia. RDW-SD, a direct measure of MCV variability, and the standard deviation of MCV (1SD-RDW) show the most statistically significant reductions in Sdh hKO mice. Tissue metabolomic profiling of 147 common metabolites shows the largest increase in succinate with elevated succinate to fumarate and succinate to oxoglutarate (2-ketoglutarate) ratios in Sdh hKO mice. These results demonstrate that mitochondrial complex II level is an underlying determinant of both RDW and healthy lifespan in hypoxia, and suggest that therapeutic targeting of Sdh might reduce high RDW-associated clinical mortality in hypoxic diseases.

Higher red cell distribution width and poorer hospitalization-related outcomes in elderly patients

BACKGROUND

Red cell distribution width (RDW), an index for variation of red blood cell (RBC) size, has been proposed as a potential marker for poorer outcomes in several aging-related diseases and conditions. We tested whether greater variability of RBC size, presented as a higher RDW value, predicts poor prognoses among hospitalized patients over 60 years old.

METHODS

We retrospectively collected data from older hospitalized patients aged ≥60 years between January 2013 to December 2017 at Sutter Health, a large integrated health system in Northern California. The RDW was measured during hospital admission and categorized with 1% intervals (≤13.9, 14.0-14.9, 15.0-15.9, 16.0-16.9, 17.0-17.9 and ≥18.0%). The primary outcome was the rate of in-hospital mortality and secondary outcomes included 30-day re-admission rate and length of hospital stay (in days).

RESULTS

A total of 167,292 admissions from 94,617 patients were included. The overall in-hospital mortality rate was 6.3%. As the RDW value increased, the rate of in-hospital mortality gradually increased from 2.7% for the lowest RDW category to 12.2% in the highest category (p-trend <0.001). The overall 30-day re-admission rate after discharge was 12.5% and the rate of 30-day re-admission also increased with increasing RDW categories (7.4% in the lowest group vs. 15.8% in the highest group, p-trend <0.001). Patients with the highest RDW values at admission stayed 1.5-2.0 times longer in the hospital than patients with lower RDW values who were admitted for the same causes.

CONCLUSIONS

Greater variability of RBC size is significantly associated with worse prognosis in hospitalized elderly patients, indicating higher mortality, greater risk of early re-admission, and longer hospital stay days. Risk stratification strategies for hospitalized elderly should include RDW value.

Exploring red cell distribution width as a biomarker for treatment efficacy in home mechanical ventilation

BACKGROUND

With the growing practice of home mechanical ventilation, there is a need to identify biological markers for adequate follow-up. Red cell distribution width (RDW) is a promising candidate because it is convenient, objective and may reflect treatment effect over a long period of time. The aim of this study was to explore the possible role of RDW as a marker for home mechanical ventilation in real-life, unselected chronic respiratory patient populations.

METHODS

First, we identified characteristic RDW values for mixed case, unselected chronic respiratory failure and home mechanical ventilated patients through retrospective review within our institutional database. Next, we conducted a prospective observational study to identify RDW changes during the first six months of optimized home mechanical ventilation treatment. Adult patients starting home mechanical ventilation were included. Factors affecting RDW change during the first 6 months of treatment were analysed.

RESULTS

RDW was elevated in both chronic respiratory failure and home mechanical ventilation patients compared to healthy individuals in the retrospective review. In the prospective study of 70 patients, we found that 55.4% of patients starting home mechanical ventilation have abnormal RDW values which are reduced from 14.7 (IQR = 13.2-16.2)% to 13.5 (IQR = 13.1-14.6)% during the first 6 months of HMV treatment (p < 0.001). RDW improvement correlates with improvement in self-reported health-related quality of life and sleepiness scale scores, as well as physical functional status during the same time frame. RDW proved to be a comparable marker to other parameters traditionally used to evaluate treatment efficacy.

CONCLUSIONS

RDW is elevated in chronic respiratory failure patients and is significantly reduced in the first six months of optimized home mechanical ventilation. Although further research is needed to verify if RDW change reflects outcome and how comorbidities influence RDW values, our results suggest that RDW is a promising marker of home mechanical ventilation efficacy. Trial registration This study was approved by and registered at the ethics committee of Semmelweis University (TUKEB 250/2017 and TUKEB 250-1/2017, 20th of December 2017 and 1st of October 2019).

Factors associated with in-hospital mortality in adult sepsis with Escherichia coli infection

Background

Escherichia coli (E. coli) is an important pathogen in sepsis. This study aimed to explore the factors which were associated with in-hospital mortality in adult sepsis with E. coli infection based on a public database.

Methods

All sepsis patients with E. coli infection in MIMIC-III were included in this study. Clinical characteristics between the survivor and non-survivor groups were analyzed. Factors associated with in-hospital mortality were identified by multivariate logistic regression.

Results

A total of 199 patients were eventually included and divided into two groups: a survivor group (n = 167) and a non-survivor group (n = 32). RDW and HCT were identified as the factors with clinical outcomes. The area under the ROC curve (AUC) were 0.633 and 0.579, respectively. When combined RDW and HCT for predicting in-hospital mortality, the AUC was 0.772, which was significantly superior to SOFA and APACHEII scores.

Conclusion

RDW and HCT were identified as factors associated with in-hospital mortality in adult sepsis patients with E. coli infection. Our findings will be of help in early and effective evaluation of clinical outcomes in those patients.

Monthly Continuous Erythropoietin Receptor Activator Versus Weekly Epoetin-Beta, Similar Hemoglobinization but Different Anisocytosis Degree in Hemodialysis Patients: A Randomized Controlled Trial

Background

The monthly continuous erythropoietin receptor activator (CERA) utilization maintains stable hemoglobin (Hb) after conversion from weekly epoetin-β (EB); however, how the different pharmacologic properties affect the red blood cell (RBC) size determined by RBC distribution width (RDW) has not been evaluated yet. We assess the potential differences in iron metabolism, plasma erythropoietin (EPO), hepcidin, and soluble α-Klotho (α-Klotho) levels as an emergent hematopoiesis factor.

Methods

Thirty-seven chronic hemodialysis patients were included from January 2010 to November 2011 and randomized (1:1) to continue with EB or to convert to monthly CERA. Primary outcome was the mean change in Hb between groups at months 0, 3 and 6, and the percentage of patients who maintained stable Hb (Hb ± 1 g/dL from baseline level to month 6). Secondary outcomes were the influence on the erythropoietic process and iron metabolism markers. Thirty-one patients completed the study (CERA: n = 15, EB: n = 16).

Results

The mean (95% confidence interval (CI)) Hb difference between groups was 0.28 g/dL (-0.36 to 0.93). There was no difference between the percentages of patients with stable Hb levels. In the CERA group RDW values increased progressively (interaction erythropoietin-stimulating agent (ESA) type and time on RDW values, F (1.57, 45.60) = 17.17, P < 0.01, partial η² = 0.37) and the mean corpuscular volume changed at the different time points, (F (2, 28) = 29.12, P = 0.03, partial η² = 0.23). During the evaluation period, in the CERA group, EPO was higher, and hepcidin and ferritin decreased significantly. α-Klotho decreased in both groups and correlated negatively with the changes on the RDW and positively with transferrin and serum iron. The number of serious adverse events was higher at the CERA group.

Conclusions

Monthly CERA maintained Hb concentrations; however, it showed a significant effect on RDW, probably due to its impact on the EPO and hepcidin levels. α-Klotho decreased significantly in both groups, and its changes correlated with the changes in iron metabolism. Whether the RDW evolution was associated with the serious adverse events (SAEs) is a feasible hypothesis that needs to be confirmed in large studies.

Can red cell distribution width in very low birth weight infants predict bronchopulmonary dysplasia?

Red cell distribution width (RDW) is a useful marker for assessing the severity and prognosis of various diseases in adults. However, whether it is applicable to children, especially in newborns, has not been determined.This study aimed to investigate the RDW values of preterm infants and evaluate whether RDW values in the early days of life can predict bronchopulmonary dysplasia (BPD) development.One hundred and eight infants born at <30 weeks of gestation with a birth weight of <1500 g participated in this retrospective study. RDW values measured at birth, 7 days (D7), and 28 days (D28) after birth were reviewed. The changes in RDW values in the first month of life were analyzed, and we evaluated the relationship between RDW and BPD.The mean RDW values at birth, D7, D28 and the change from birth to D7 were 16.2 ± 0.1%, 17.5 ± 0.2%, 17.6 ± 0.2% and 1.3 ± 1.8%, respectively. RDW at birth was lower in the infants born at <28 weeks' gestational age than in those born at ≥28 weeks' gestational age (15.7 ± 0.3 vs 16.4 ± 0.2, P = .024). RDW values of both groups increased during the first week after birth and did not differ significantly at D7. The levels remained similar at 1 month of age. RDW at birth, D7, and D28 and the changes in RDW from birth to D7 were not correlated with the development of BPD independent of its severity.The usefulness of RDW as a predictor of BPD development remains questionable and requires further study.

Association of Red Blood Cell Distribution Width-Albumin Ratio for Acute Myocardial Infarction Patients with Mortality: A Retrospective Cohort Study

BACKGROUND

Red blood cell distribution width (RDW) was a risk factor for poor prognosis in acute myocardial infarction (AMI). Recent reports suggested that combining RDW with other laboratory metrics could provide a better prediction. This retrospective study aimed to investigate whether the RDW-albumin ratio (RAR) may be associated with mortality after an AMI.

METHODS

This cohort study was conducted among adults (over 16 years old) with AMI in the Medical Information Mart for Intensive Care Database III V1.4 (MIMIC-III). The primary outcome was 30-day mortality, and the secondary outcome was 1-year and 3-year mortality. Cox hazard regression model and Kaplan-Meier survival curves were constructed to estimate the effect of biomarkers on mortality. We used three models to adjust for potential bias. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were analyzed for the excellent performance of RAR on prognosis.

RESULTS

A total of 826 patients were eventually enrolled in our study. In multivariate analysis, RAR was found to be associated with 30-day mortality (Model 3: HR = 1.23, 95% CI = 1.09-1.39, P < .001). In addition, Subgroup analysis showed that the effect of RAR was higher in female patients than in male patients (P for interaction = .026). Kaplan-Meier survival curves showed that patients in the lower RAR quartile tended to have higher survival rates in the short and long term. AMI patients with RAR ≥ 4 had a 122% increase in 3-year mortality. Results of ROC and AUC showed that the prognostic performance of RAR for mortality was the best (30-day mortality: 0.703; 1-year mortality: 0.729; 3-year mortality: 0.737).

CONCLUSIONS

RAR is a simple and stable predictor of prognosis in AMI patients. Our results support RAR = 4.0 as a criterion for prognostic risk stratification of AMI patients.

EpoR stimulates rapid cycling and larger red cells during mouse and human erythropoiesis

The erythroid terminal differentiation program couples sequential cell divisions with progressive reductions in cell size. The erythropoietin receptor (EpoR) is essential for erythroblast survival, but its other functions are not well characterized. Here we use Epor-/- mouse erythroblasts endowed with survival signaling to identify novel non-redundant EpoR functions. We find that, paradoxically, EpoR signaling increases red cell size while also increasing the number and speed of erythroblast cell cycles. EpoR-regulation of cell size is independent of established red cell size regulation by iron. High erythropoietin (Epo) increases red cell size in wild-type mice and in human volunteers. The increase in mean corpuscular volume (MCV) outlasts the duration of Epo treatment and is not the result of increased reticulocyte number. Our work shows that EpoR signaling alters the relationship between cycling and cell size. Further, diagnostic interpretations of increased MCV should now include high Epo levels and hypoxic stress.

Preferential Metabolic Improvement by Intermittent Fasting in People with Elevated Baseline Red Cell Distribution Width: A Secondary Analysis of the WONDERFUL Randomized Controlled Trial

Red cell distribution width (RDW) predicts cardiovascular outcomes, but it is unstudied with regard to intermittent fasting. In WONDERFUL trial subjects, the effect of the interaction between baseline RDW and intermittent fasting on changes in insulin and other cardiometabolic endpoints and the effect of fasting on changes in RDW were evaluated. The subjects enrolled were aged 21-70 years and were free of statins, anti-diabetes medications, and chronic diseases, and had ≥1 metabolic syndrome feature, as well as elevated low-density lipoprotein cholesterol. Subjects were randomized to 24-h, water-only fasting (twice per week for 4 weeks, once per week for 22 weeks) or 26 weeks of ad libitum eating. Subjects (N = 71; n = 38 intermittent fasting, n = 33 controls) had more substantial changes in insulin in intermittent fasting vs. controls (-3.45 ± 2.27 vs. 0.48 ± 3.55 mIU/L) when baseline RDW size distribution (RDW-SD) was ≥median (42.6 fL) than Collapse

Key Words

• RDW
• RDW-CV
• RDW-SD
• intermittent fasting
• therapeutic fasting

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MESH Headings

• Adult
• Aged
• Biomarkers/blood
• Cardiovascular Diseases/diagnosis
• Cardiovascular Diseases/etiology
• Cardiovascular Diseases/metabolism
• Cardiovascular Diseases/prevention & control
• Cholesterol, LDL/metabolism
• Erythrocyte Indices
• Fasting/physiology
• Female
• Heart Disease Risk Factors
• Humans
• Insulin/metabolism
• Male
• Middle Aged
• Randomized Controlled Trials as Topic
• Young Adult

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Grants

• 759 Intermountain Research and Medical Foundation
• Dell Loy Hansen Heart Foundation Intermountain Research and Medical Foundation

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Affiliation(s)

Benjamin D. Horne Intermountain Medical Center Heart Institute, Salt Lake City, UT 84107, USA; (J.B.M.); (H.T.M.); (V.T.L.); (T.L.B.); (K.U.K.); (J.L.A.) Division of Cardiovascular Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA
Joseph B. Muhlestein Intermountain Medical Center Heart Institute, Salt Lake City, UT 84107, USA; (J.B.M.); (H.T.M.); (V.T.L.); (T.L.B.); (K.U.K.); (J.L.A.) Cardiology Division, Department of Internal Medicine, University of Utah, Salt Lake City, UT 84132, USA
Heidi T. May Intermountain Medical Center Heart Institute, Salt Lake City, UT 84107, USA; (J.B.M.); (H.T.M.); (V.T.L.); (T.L.B.); (K.U.K.); (J.L.A.)
Viet T. Le Intermountain Medical Center Heart Institute, Salt Lake City, UT 84107, USA; (J.B.M.); (H.T.M.); (V.T.L.); (T.L.B.); (K.U.K.); (J.L.A.) Department of Physician Assistant Studies, College of Medical and Health Professional Science, Rocky Mountain University of Health Professions, Provo, UT 84606, USA
Tami L. Bair Intermountain Medical Center Heart Institute, Salt Lake City, UT 84107, USA; (J.B.M.); (H.T.M.); (V.T.L.); (T.L.B.); (K.U.K.); (J.L.A.)
Sterling T. Bennett Intermountain Central Laboratory, Intermountain Medical Center, Salt Lake City, UT 84107, USA; Department of Pathology, University of Utah, Salt Lake City, UT 84132, USA
Kirk U. Knowlton Intermountain Medical Center Heart Institute, Salt Lake City, UT 84107, USA; (J.B.M.); (H.T.M.); (V.T.L.); (T.L.B.); (K.U.K.); (J.L.A.) Division of Cardiovascular Medicine, Department of Medicine, University of California San Diego, San Diego, CA 92093, USA
Jeffrey L. Anderson Intermountain Medical Center Heart Institute, Salt Lake City, UT 84107, USA; (J.B.M.); (H.T.M.); (V.T.L.); (T.L.B.); (K.U.K.); (J.L.A.) Cardiology Division, Department of Internal Medicine, University of Utah, Salt Lake City, UT 84132, USA

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A Meta-analysis of the Utility of Red Cell Distribution Width as a Biomarker to Predict Outcomes in Pediatric Illness (PROSPERO CRD42020208777)

Red cell distribution width (RDW) is an average of the variation in red blood cell (RBC) sizes reported on a complete blood count. An elevated RDW indicates a pathological process that is affecting erythropoiesis. Studies showed that as the severity of disease process increases, the RDW often increases as well. Particularly in resource-limited countries, RDW has been studied as an outcome predictor for conditions in a variety of disciplines and is offered as an adjunct monitoring tool that is cost effective, readily available, and indicative of pathological processes amenable to intervention. Particularly in pediatric critical care settings, RDW has been shown to be a reliable tool for surveillance of disease states such as sepsis. Despite the increased attention of RDW as a marker for disease outcome, collective evaluation on the utility of RDW as a marker for outcome in pediatric critical care settings is lacking. We offer a systematic review and meta-analysis of published studies to assess the ability of RDW to predict illness severity and mortality among pediatric critical care patients. Among eight studies of over 4,800 patients, we found over a two-fold increase in odds for mortality in critically ill children whose RDW was above 15.7%. This is the first systematic review of RDW being used to predict mortality in critically ill children and findings of this study may prompt early intervention in the pediatric critical care setting.

Impact of red blood cell distribution width and mean platelet volume in patients with ST-segment elevation myocardial infarction

The complete blood cell count is one of the most frequently ordered laboratory tests, and many parameters, including red blood cell distribution width (RDW) and mean platelet volume (MPV), are available. The purpose of this study was to investigate the usefulness of the combination of RDW and MPV in patients with ST-segment elevation myocardial infarction (STEMI). Patients with STEMI who underwent primary percutaneous coronary intervention were retrospectively enrolled (n = 229). The association between RDW as well as MPV and cardiovascular events was investigated. The median age was 67 years, and males made up 85% of the sample. Median RDW was 13.6%, and median MPV was 8.2 fL. During a median follow-up period of 528 days (IQR 331.5-920.5), 41 patients died or experienced major adverse cardiac and cerebrovascular events (MACCEs). Patients with RDW ≧ 13.7% had more deaths or MACCEs with marginal significance (p = 0.0799). Patients with MPV ≧ 8.3 fL had significantly more deaths or MACCEs (p = 0.0283). Patients with RDW ≧ 13.7% and MPV ≧ 8.3 fL had significantly more deaths or MACCEs (p = 0.0185). MPV was significantly associated with death or adverse events in patients with STEMI who were treated with primary PCI. RDW had only a weak association with death or adverse events. The results of the combination of MPV and RDW were similar to those of MPV.

Magnetophoretic and spectral characterization of oxyhemoglobin and deoxyhemoglobin: Chemical versus enzymatic processes

A new method for hemoglobin (Hb) deoxygenation, in suspension or within red blood cells (RBCs) is described using the commercial enzyme product, EC-Oxyrase®. The enzymatic deoxygenation method has several advantages over established deoxygenation methodologies, such as avoiding side reactions that produce methemoglobin (metHb), thus eliminating the need for an inert deoxygenation gas and airtight vessel, and facilitates easy re-oxygenation of Hb/RBCs by washing with a buffer that contains dissolved oxygen (DO). The UV-visible spectra of deoxyHb and metHb purified from human RBCs using three different preparation methods (sodium dithionite [to produce deoxyHb], sodium nitrite [to produce metHb], and EC-Oxyrase® [to produce deoxyHb]) show the high purity of deoxyHb prepared using EC-Oxyrase® (with little to no metHb or hemichrome production from side reactions). The oxyHb deoxygenation time course of EC-Oxyrase® follows first order reaction kinetics. The paramagnetic characteristics of intracellular Hb in RBCs were compared using Cell Tracking Velocimetry (CTV) for healthy and sickle cell disease (SCD) donors and oxygen equilibrium curves show that the function of healthy RBCs is unchanged after EC-Oxyrase® treatment. The results confirm that this enzymatic approach to deoxygenation produces pure deoxyHb, can be re-oxygenated easily, prepared aerobically and has similar paramagnetic mobility to existing methods of producing deoxyHb and metHb.

RDW-based clinical score to predict long-term survival in community-acquired pneumonia: a European derivation and validation study

An excess long-term mortality has been observed in patients who were discharged after a community-acquired pneumonia (CAP), even after adjusting for age and comorbidities. We aimed to derive and validate a clinical score to predict long-term mortality in patients with CAP discharged from a general ward. In this retrospective observational study, we derived a clinical risk score from 315 CAP patients discharged from the Internal Medicine ward of Cuneo Hospital, Italy, in 2015-2016 (derivation cohort), which was validated in a cohort of 276 patients discharged from the pneumology service of the Barakaldo Hospital, Spain, from 2015 to 2017, and from two internal medicine wards at the Turin University and Cuneo Hospital, Italy, in 2017. The main outcome was the 18-month follow-up all-cause death. Cox multivariate analysis was used to identify the predictive variables and develop the clinical risk score in the derivation cohort, which we applied in the validation cohort. In the derivation cohort (median age: 79 years, 54% males, median CURB-65 = 2), 18-month mortality was 32%, and 18% in the validation cohort (median age 76 years, 55% males, median CURB-65 = 2). Cox multivariate analysis identified the red blood cell distribution width (RDW), temperature, altered mental status, and Charlson Comorbidity Index as independent predictors. The derived score showed good discrimination (c-index 0.76, 95% CI 0.70-0.81; and 0.83, 95% CI 0.78-0.87, in the derivation and validation cohort, respectively), and calibration. We derived and validated a simple clinical score including RDW, to predict long-term mortality in patients discharged for CAP from a general ward.

Red cell distribution width: A new parameter for predicting the risk of exacerbation in COPD patients

BACKGROUND

Red cell distribution width (RDW) is a numerical measurement of the size variability of erythrocytes and is routinely reported as a component of complete blood count in the differential diagnosis of anemia. In recent years, researchers have reported high mortality and poor prognosis associated with higher RDW in populations with cardiovascular disease, cancer, pneumonia, and chronic obstructive pulmonary disease (COPD). The aim of the study is to evaluate the role of RDW in predicting the risk of COPD exacerbations and the impact of symptoms.

METHODS

We designed an observational retrospective study based on patients hospitalized for acute exacerbation of COPD, between January 2015 and December 2018.

RESULTS

We included 169 patients, 120 at GOLD four stage. RDW was significantly higher in COPD patients vs controls (P = .014). We found a positive correlation with c-reactive protein (r  = 0.375, P < .01), COPD assessment test (CAT) Score (R2 = 0.658, sy.x = 2.226; P < .01), number of exacerbations (R2=0.289; sy.x = 0.86; P = .002), and GOLD score (r = 0.30; P = .05). In ROC curve analysis, the area under the curve of RDW for the identification of frequent exacerbator was 1.0 (95% confidence interval, 1.0-1.0; P < .0001).

CONCLUSION

Our data show that elevated RDW may be a useful tool in predicting the risk of exacerbation in COPD patients and may be a good indicator of the impact of symptoms.

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.

Red Cell Distribution Width and Mean Platelet Volume in Rheumatoid Arthritis Patients: Its Association With Disease Activity

INTRODUCTION

Hemogram parameters have been recently proposed as markers of inflammation in various studies from different parts of the world. Two of these hemogram parameters are red cell distribution width (RDW) and mean platelet volume (MPV).

AIM

To evaluate the relation between RDW and MPV with disease activity of rheumatoid arthritis. To assess whether RDW and MPV can be used to follow disease activity in RA patients.

METHODS

This is an observational cross-sectional study that was carried out on 60 rheumatoid arthritis patients who fulfilled the ACR/EULAR2010 classification criteria of RA attending to Rheumatology and Rehabilitation inpatient and outpatient clinics at Zagazig University Hospitals. All cases were subjected to full history taking, clinical examination, and laboratory investigations; differential complete blood picture (CBC), acute phase reactants (CRP and ESR), rheumatoid factor (RF) and anti-cyclic-citrullinated peptide (anti-CCP) antibodies. Disease activity was measured by disease activity score 28 (DAS28).

RESULTS

The cut-off levels of RDW and MPV were 14.85 and 11.25. Patients with RDW>14.85 had higher Disease Activity Score 28 (DAS28; p=0.0003), ESR (p=0.0001) and CRP (p=0.0001). RDW was positively correlated with disease activity markers (ESR, CRP and DAS28) in rheumatoid arthritis patients. But, DAS28 was not different between patients with MPV>11.25 and <11.25.

CONCLUSION

RDW was strongly correlated with disease activity. Also, RDW was better than ESR and CRP in detecting RA disease activity. According to these findings we suggest that RDW can be used in clinics to follow disease activity. In addition, RDW is widely available; as it's usually included in routine complete blood picture and there will be no need for further cost.

Low Hemoglobin-to-Red Cell Distribution Width Ratio Is Associated with Disease Progression and Poor Prognosis in Upper Tract Urothelial Carcinoma

The importance of blood cell markers in patients with malignant tumors has been studied, but there are few studies on the prognostic value of hemoglobin-to-red cell distribution width ratio (HRR) in cancer. This is the first study to investigate the effect of preoperative HRR on patients with upper tract urothelial carcinoma (UTUC). Our retrospective cohort study included 730 UTUC patients who underwent nephroureterectomy from 2000 to 2019. Clinicopathological parameters were compared according to HRR levels, and the relationship between blood cell markers (HRR, white blood cell [WBC] count, platelet count) and prognosis was evaluated using Kaplan-Meier method and Cox regression model. We found that patients with HRR ≤ 1.05 tended to have worse renal function, higher pathological stages, and more high-grade tumors. In univariate analysis, HRR ≤ 1.05, WBC > 8.65 × 10³ cells/μL and platelets >309 × 10³ cells/μL were associated with poor progression-free survival (PFS), cancer-specific survival (CSS), and overall survival (OS). Multivariate analysis demonstrated that HRR ≤ 1.05 and WBC > 8.65 × 10³ cells/μL were independent prognostic factors for predicting deterioration of PFS, CSS, and OS. In conclusion, HRR and WBC are easy to obtain in clinical practice and are useful indicators to provide prognostic information before surgery for UTUC.

Red cell distribution width as a predictor for bronchopulmonary dysplasia in premature infants

Bronchopulmonary dysplasia (BPD) is the most common morbidity complicating preterm birth. Red blood cell distribution width (RDW), a measure of the variation of red blood cell size, could reflect oxidative stress and chronic inflammation in many diseases such as cardiovascular, pulmonary, and other diseases. The objectives of the present study were to evaluate perinatal factors affecting RDW and to validate whether RDW could be a potential biomarker for BPD. A total of 176 preterm infants born at < 30 weeks were included in this study. They were categorized into BPD (n = 85) and non-BPD (n = 91) infants. RDW at birth and 14 days and 28 days of life (DOL 14, DOL 28) were measured. Clinical data were obtained from all subjects at Fukushima Medical University (Fukushima, Japan). The mean RDW at birth, DOL 14 and DOL 28 were 16.1%, 18.6%, 20.1%, respectively. Small for gestational age (SGA), chorioamnionitis (CAM), hypertensive disorders of pregnancy (HDP), gestational age and birth weight were significantly associated with RDW at birth. SGA, BPD and red blood cell (RBC) transfusion before DOL 14 were associated with RDW at DOL 14. BPD and RBC transfusion before DOL 14 were associated with RDW at DOL 28. Compared with non-BPD infants, mean RDW at DOL 14 (21.1% vs. 17.6%, P < 0.001) and DOL 28 (22.2% vs. 18.2%, P < 0.001) were significantly higher in BPD infants. Multivariate analysis revealed that RDW at DOL 28 was significantly higher in BPD infants (P = 0.001, odds ratio 1.63; 95% CI 1.22–2.19). Receiver operating characteristic analysis for RDW at DOL 28 in infants with and without BPD yielded an area under the curve of 0.87 (95% CI 0.78–0.91, P < 0.001). RDW at DOL 28 with mild BPD (18.1% vs. 21.3%, P < 0.001), moderate BPD (18.1% vs. 21.2%, P < 0.001), and severe BPD (18.1% vs. 24.0%, P < 0.001) were significantly higher than those with non-BPD, respectively. Furthermore, there are significant differences of RDW at DOL 28 among mild, moderate, and severe BPD. In summary, we conclude that RDW at DOL 28 could serve as a biomarker for predicting BPD and its severity. The mechanism by which RDW at DOL 28 is associated with the pathogenesis of BPD needs further elucidation.

Donor Age and Red Cell Age Contribute to the Variance in Lorrca Indices in Healthy Donors for Next Generation Ektacytometry: A Pilot Study

The ability of red blood cells (RBCs) to transport gases, their lifespan as well as their rheological properties invariably depend on the deformability, hydration, and membrane stability of these cells, which can be measured by Laser optical rotational red cell analyser (Lorrca® Maxsis, RR Mechatronics). The osmoscan mode of Lorrca is currently used in diagnosis of rare anemias in clinical laboratories. However, a broad range of normal values for healthy subjects reduces the sensitivity of this method for diagnosis of mild disease phenotype. In this pilot study, we explored the impact of age and gender of 45 healthy donors, as well as RBC age on the Lorrca indices. Whereas gender did not affect the Lorrca indices in our study, the age donors had a profound effect on the O_hyper parameter. To study the impact of RBC age on the osmoscan parameters, we have isolated low (L)-, medium (M)-, or high (H)- density fractions enriched with young, mature, and senescent RBCs, respectively, and evaluated the influence of RBC age-related properties, such as density, morphology, and redox state, on the osmoscan indices. As before, O_hyper was the most sensitive parameter, dropping markedly with an increase in RBC density and age. Senescence was associated with a decrease in deformability (EI_max) and tolerability to low and high osmolatites (Area). L-fraction was enriched with reticulocytes and cells with high projected area and EMA staining, but also contained a small number of cells small in projected area and most likely, terminally senescent. L-fraction was on average slightly less deformable than mature cells. The cells from the L-fraction produced more oxidants and NO than all other fractions. However, RBCs from the L-fraction contained maximal levels of reduced thiols compared to other fractions. Our study suggests that reference values for O_hyper should be age-stratified, and, most probably, corrected for the average RBC age. Further multi-center study is required to validate these suggestions before implementing them into clinical practice.

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.

Dynamic Increase of Red Cell Distribution Width Predicts Increased Risk of 30-Day Readmission in Patients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Purpose

Studies have demonstrated that red blood cell distribution width (RDW) is closely associated with the prognosis of patients with chronic obstructive pulmonary disease (COPD). In addition, the dynamic changes in RDW appear to play an important role. Thus, we aimed to investigate the relationship between dynamic changes in RDW and 30-day all-cause readmission of patients with acute exacerbation of COPD (AECOPD).

Methods

In this retrospective cohort study, we enrolled patients with AECOPD hospitalized in the Department of Respiratory Medicine in Liyuan Hospital (Wuhan China), a tertiary, university-affiliated, public hospital. Patients with AECOPD were divided into three groups based on their RDW values after the first and fourth days of admission. The normal range for RDW is 10-15%. Patients with normal RDW values were included in the normal group. Patients with an RDW value >15% on the first day, which subsequently decreased by >2% on the fourth day was included in the decreased group. The increased group was comprised of patients with an RDW value >15% on the first day which continued to increase, or those with a normal RDW value on the first day which increased >15% on the fourth day.

Results

A total of 239 patients (age: 72 years [range: 64-81 years]; male: n=199 [83.3%]) were included. There were 108, 72, and 59 patients in the RDW normal, decreased, and increased groups, respectively; the 30-day all-cause readmission rate was 9.3%, 9.7%, 27.1%, respectively; (p=0.003), being noticeably higher in the RDW increased group. Dynamic increase of RDW (OR:3.45, 95% CI: 1.39-8.58, p= 0.008) was independently correlated with 30-day all-cause readmission of patients with AECOPD.

Conclusion

The dynamic increase of RDW is an independent prognostic factor of 30-day all-cause readmission of patients with AECOPD.

Prognostic Significance of Red Cell Distribution Width in Idiopathic Pulmonary Fibrosis and Combined Pulmonary Fibrosis Emphysema

OBJECTIVE

The red cell distribution width (RDW) is an inexpensive, readily available prognostic indicator of several diseases. RDW has been assessed as a prognostic biomarker in patients with idiopathic pulmonary fibrosis (IPF) in only one study; furthermore, the relationship between the RDW and combined pulmonary fibrosis emphysema (CPFE) has yet to be reported.

SUBJECTS AND METHODS

This single-center study was conducted between January 2015 and December 2018 in the Atatürk Chest Diseases and Chest Surgery Education and Research Hospital. Baseline characteristics, laboratory results, and survival status of patients were recorded.

RESULTS

The RDW value was significantly higher in the CPFE group than in the IPF group (median [IQR 25-75]; 16.8 [15.5-19] vs. 15.3 [13.7-16.8], p = 0.028). High RDW values were correlated with carbon monoxide diffusion capacity (DLCO) (r: -0.653 p = 0.001), 6-minute walking test (6MWT) distance (r: -0.361 p = 0.017), arterial partial oxygen pressure (PaO2) (r: -0.692 p < 0.001), and systolic pulmonary arterial pressure (SPAP) (r: 0.349 p = 0.022) in patients with fibrotic lung disease. The RDW value was significantly higher in the exitus group than in the survivors (median [IQR 25-75]; 18.4 [15.4-19] vs. 15.2 [13.5-17.2], p = 0.016). A univariate Cox regression analysis identified DLCO, SPAP, PaO2, and RDW as potential covariates of mortality. In a multivariate analysis, the DLCO (HR 1.21, 95% CI 1.11-1.47, p = 0.012) and RDW level (HR 1.65, 95% CI 1.09-2.47, p = 0.023) remained independent predictors of mortality.

CONCLUSION

High RDW values appear to be a simple prognostic factor in patients with IPF or CPFE.

Association between red blood cell distribution width and long-term mortality in acute respiratory failure patients

The red cell distribution width (RDW) has been reported to be positively correlated with short-term mortality of pulmonary disease in adults. However, it is not clear whether RDW was associated with the long-term prognosis for acute respiratory failure (ARF). Thus, an analysis was conducted to evaluate the association between RDW and 3-year mortality of patients by the Cox regression analysis, generalized additives models, subgroup analysis and Kaplan–Meier analysis. A total of 2999 patients who were first admitted to hospital with ARF were extracted from the Medical Information Mart for Intensive Care III database (MIMIC-III). The Cox regression analysis showed that the high RDW was associated with 3-year mortality (HR 1.10, 95% CI 1.07, 1.12, P < 0.0001) after adjusting for age, gender, ethnicity and even co-morbid conditions. The ROC curve illustrated the AUC of RDW was 0.651 (95% CI 0.631, 0.670) for prediction of 3-year mortality. Therefore, there is an association between the RDW and survival time of 3 years follow-up, particularly a high RDW on admission was associated with an increased risk of long-term mortality in patients with ARF. RDW may provide an alternative indicator to predict the prognosis and disease progression and more it is easy to get.

Red cell distribution width: a new tool for the severity prediction of sleep apnoea syndrome in children

Introduction

Red cell distribution width (RDW) is a parameter included in the complete blood count which informs about the size of the circulating red blood cell population and its distribution. In adults, an increase in RDW was shown to be associated both with obstructive sleep apnoea (OSA) and with an increase in cardiovascular mortality. The aim of this study was to determine whether RDW is a potential biomarker for screening children with moderate–severe OSA.

Methods

An observational study in snoring patients was performed. All patients underwent a sleep study and were classified either as simple snorers (apnoea–hypopnoea index (AHI) <1 event·h⁻¹) or as patients with OSA (mild AHI ≥1 to <5 events·h⁻¹; moderate–severe AHI ≥5 events·h⁻¹). Blood analyses (complete blood count and C-reactive protein) were performed for every individual.

Results

A total of 175 individuals were recruited. The mean age was 8.3±3.6 years. Correlation studies between RDW and several sleep-related parameters showed negative significant associations with minimum oxygen saturation, and positive significant associations with oxygen desaturation index (≥3% and ≥4%), AHI and the arousal index. A predictive model for paediatric severe OSA (AHI ≥5 events·h⁻¹) was found based on mean corpuscular haemoglobin concentration (MCHC) <34.9 g·dL⁻¹ and RDW >13.1% values, adjusting for body mass index z-score and age (area under the curve 0.657; p=0.004). In addition, differences were found in eosinophil count and C-reactive protein concentrations among the three subgroups.

Conclusions

In children, RDW stands out as a biomarker associated with the severity of OSA. The use of RDW and MCHC could be a simple but useful tool for the severity prediction of paediatric OSA in snoring patients.

Red cell distribution width and mean corpuscular haemoglobin concentration are blood markers associated with the severity of paediatric OSAhttps://bit.ly/2Asw1xa

CHANGES IN THE MORPHOLOGIC STATE OF RED BLOOD CELLS IN PATIENTS WITH POLYTRAUMA

The measurement of RBC indices is of particular importance as an indirect intermediate component of the recovery process after exposure to hypoxia, ischemia, hypothermia in patients with traumatic disease due to polytrauma. The aim of this study was to evaluate the parameters of the morphologic state of red blood cells as a reaction of patients with traumatic disease. Materials and methods.A prospective study was carried out evaluation of 120 patients suffering from polytrauma. The patients were divided into 3 groups according to the principle of using additional substances as a part of IC. The parameters of morphologic state of red blood cells were studied. Results and discussion. The course of acute and early periods of traumatic disease has accompanied variability morphological forms of red blood cells, as evidenced by a decrease in MCV and RDW increased levels of the 3rd to 5th day. The optimized therapy used in the treatment of patients, has a positive effect on the parameters of red blood cells, contributes to a better recovery of red blood cells after hypoxia resulting multiple trauma. Conclusion. The study has demonstrated variations in the morphologic properties of red blood cells in the acute and early period of traumatic disease, as confirmed by pathological changes of the erythrocyte indices. The administration of the proposed therapy with the use of D-fructose-1.6-diphosphate sodium salt of hydrate has a positive effect on the parameters of red blood cells, contributes to a better recovery after hypoxia resulting multiple trauma. Given this, the calculations of the red blood cell indices may carry additional diagnostic information, which allows identify trends for not obvious pathological changes and quality of treatment.

Association between red blood cell distribution width and mortality in diabetic ketoacidosis

Background

No epidemiological studies have assessed the impact of red blood cell distribution width (RDW) on the prognosis of diabetic ketoacidosis (DKA) patients in the intensive care unit (ICU). Thus, we investigated whether RDW was associated with mortality in DKA patients.

Material and method

We analyzed data from MIMIC-III. RDW was measured at ICU admission. The relationship between RDW and mortality of DKA was determined using a multivariate Cox regression analysis. The primary outcome of the study was 365-day mortality from the date of ICU admission. We also conducted a subgroup analysis to further confirm the consistency of associations.

Results

In total, 495 critically ill DKA patients were eligible for analysis. In the univariable Cox regression model for 365-day all-cause mortality, RDW was a predictor of all-cause mortality in DKA patients (hazard ratio [HR]: 1.30, 95% confidence interval [CI]: 1.19–1.43). After adjusting for confounders, RDW was still a particularly strong predictor (HR: 1.23, 95% CI: 1.05–1.45). The same relationship was also observed for 90-day all-cause mortality (HR: 1.29, 95% CI: 1.02–1.65).

Conclusions

High RDW was associated with risk of all-cause mortality in DKA patients in the ICU. RDW was an independent prognostic factor for these patients.

Altered Hemorheology in Fontan Patients in Normoxia and After Acute Hypoxic Exercise

Background

The Fontan circulation is a unique palliation procedure for several congenital heart defects. Impaired exercise capacity has previously been demonstrated in these patients and also a higher risk for cardiopulmonary mortality. Hemorheology was shown to affect cardiopulmonary capacity and in turn to be affected by regular exercise and hypoxia but none of these have been investigated in Fontan patients so far. The aim of this study was to detect general differences in hemorheology in normoxia as well as possible altered hemorheological responses to hypoxia exposure and hypoxic exercise between Fontan patients and healthy controls.

Methods and Findings

26 Fontan patients and 20 healthy controls performed an acute exercise test (AET) on a bicycle ergometer under hypoxia with ambient 15.2% oxygen saturation (sO₂). Blood samples were taken at rest in normoxia (T0), at rest in hypoxia (T1), after maximum exhaustion in hypoxia (T2), and after 50 min recovery in normoxia (T3). Hemorheological and blood parameters were investigated. Additionally, arterial stiffness was tested at T0. Red blood cell (RBC) deformability, NOx, erythropoietin (EPO) concentration, RBC count, hemoglobin (Hb) concentration and hematocrit (hct) were significantly increased in Fontan patients compared to controls. Same was observed for arterial stiffness. No changes were observed for RBC aggregation, fibrinogen concentration, free radical levels and vascular endothelial growth factor (VEGF). Hypoxia exposure did not change parameters, whereas exercise in hypoxia increased aggregation and hct significantly in both groups. Fontan patients showed significantly increased aggregation-disaggregation balance compared to controls.

Conclusion

Acute hypoxia exposure and exercise under hypoxia might have similar impact on hemorheology in Fontan patients and controls and was clinically well tolerated. Nevertheless, exercise alters aggregation and possibly hemodynamics which requires special attention in Fontan patients.

Red cell distribution width, platelet-to-lymphocyte ratio, and mean platelet volume in ankylosing spondylitis and their correlations with inflammation: A meta-analysis

Objectives: To evaluate the relationship between red cell distribution width (RDW), platelet-to-lymphocyte ratio (PLR), and mean platelet volume (MPV) and ankylosing spondylitis (AS) and establish a correlation between these haematological indices and AS inflammation.Methods: We searched the Medline, Embase, and Cochrane databases, performed a meta-analysis comparing RDW, PLR, and MPV in patients with AS to controls, and examined correlation coefficients between RDW, PLR, and MPV and C-reactive protein (CRP).Results: Eleven studies were included in this meta-analysis, which revealed that RDW was significantly higher in the AS group than in the control group (standardized mean difference (SMD) = 0.687, 95% confidence interval (CI) = 0.110-1.265, p = .020). However, PLR was not significantly higher in the AS group than in the control group (SMD = 0.197, 95% CI = -0.045-0.439, p = .111). No evidence of elevated MPV in the AS group was found (SMD = -0.005, 95% CI = -0.411-0.400, p = .979). Meta-analysis of correlation coefficients revealed that RDW was positively associated with CRP (correlation coefficient = 0.327, 95% CI = 0.214-0.431, p < .001). PLR was positively associated with CRP (correlation coefficient = 0.444, 95% CI = 0.283-0.581, p < .001). In addition, the meta-analysis showed a correlation between MPV and CRP (correlation coefficient = 0.217, 95% CI = 0.080-0.346, p = .002).Conclusion: This meta-analysis demonstrated that RDW is higher in patients with AS, and a significant positive correlation exists between RDW, PLR, and MPV and CRP.

Unbiased Phenome-Wide Association Studies of Red Cell Distribution Width Identifies Key Associations with Pulmonary Hypertension

Rationale: Red cell distribution width (RDW) is a prognostic factor in many diseases; however, its clinical utility remains limited because the relative value of RDW as a biomarker across disease states has not been established. Objectives: To establish an unbiased RDW disease hierarchy to guide the clinical use of RDW and to assess its relationship to cardiovascular hemodynamic and structural parameters. Methods: We performed phenome-wide association studies for RDW in discovery and replication cohorts derived from a deidentified electronic health record in nonanemic individuals. RDW values obtained within 30 days of echocardiogram or right heart catheterization were tested for association with structural and hemodynamic variables. Results: RDW was associated with 263 phenotypes in both men and women in the discovery cohort (n = 121,530), 48 of which replicated in an independent cohort (n = 2,039). The strongest associations were observed with pulmonary arterial hypertension (odds ratio [OR], 2.1; 95% confidence interval [CI], 1.9-2.3), chronic pulmonary heart disease (OR, 2.0; 95% CI, 1.9-2.2), and congestive heart failure (OR, 1.9; 95% CI, 1.8-2.0); P < 1 × 10-74 for all. By echocardiography, RDW was higher in the setting of right ventricular dysfunction than left ventricular dysfunction (P < 0.001). Measured invasively, mean pulmonary arterial pressure was associated with RDW (21 vs. 33 mm Hg at 25th vs. 75th percentile RDW; P < 1 × 10-7) and remained strongly significant even when controlling for mean pulmonary capillary wedge pressure (21 vs. 29 mm Hg at 25th vs. 75th percentile RDW; P < 1 × 10-7). Conclusions: Among 1,364 coded medical conditions, increased RDW was strongly associated with pulmonary hypertension and heart failure. Hemodynamic and echocardiographic phenotyping confirmed these associations and underscored that the most clinically relevant phenotype associated with RDW was pulmonary hypertension. These hypothesis-generating findings highlight the potential shared pathophysiology of pulmonary hypertension and elevated RDW. Elevated RDW in the absence of anemia should alert clinicians to the potential for underlying cardiopulmonary disease.