Incremental predictive value of red cell distribution width for 12-month clinical outcome after acute myocardial infarction

Red Blood Cell Distribution Width to Albumin Ratio for Predicting Type I Cardiorenal Syndrome in Patients with Acute Myocardial Infarction: A Retrospective Cohort Study

Purpose

Red blood cell distribution width to albumin ratio (RAR) is a novel inflammatory biomarker that independently predicts adverse cardiovascular events and acute kidney injury. This study aimed to assess the predictive value of RAR for cardio-renal syndrome type I (CRS-I) risk in acute myocardial infarction (AMI) patients.

Patients and methods

This study retrospectively enrolled 551 patients who were definitively diagnosed as AMI between October 2021 and October 2022 at the Affiliated Zhongda Hospital of Southeast University. Participants were divided into two and four groups based on the occurrence of CRS-I and the quartiles of RAR, respectively. Demographic data, laboratory findings, coronary angiography data, and drug utilization were compared among the groups. Logistic regression and receiver operating characteristic curve (ROC) analysis were performed to identify independent risk factors for CRS-I and evaluated the predictive value of RAR for CRS-I.

Results

Among the cohort of 551 patients, 103 (18.7%) developed CRS-I. Patients with CRS-I exhibited significantly elevated RAR levels compared to those without the condition, and the incidence of CRS-I correlated with escalating RAR. Univariate and multivariate logistic regression analyses identified RAR as an independent risk factor for CRS-I. ROC curves analysis demonstrated that RAR alone predicted CRS-I with an area under the curve (AUC) of 0.683 (95% CI=0.642-0.741), which was superior to the traditional inflammatory marker C-reactive protein (CRP). Adding the variable RAR to the model for predicting the risk of CRS-I further improved the predictive value of the model from 0.808 (95% CI=0.781-0.834) to 0.825 (95% CI=0.799-0.850).

Conclusion

RAR is an independent risk factor for CRS-I, and high levels of RAR are associated with an increased incidence of CRS-I in patients with AMI. RAR emerges as a valuable and readily accessible inflammatory biomarker that may play a pivotal role in risk stratification in clinical practice.

Red blood cell distribution width (RDW) - A new nutritional biomarker to assess nutritional risk and response to nutritional therapy?

BACKGROUND & AIMS

Red cell distribution width (RDW) has been proposed as a surrogate marker for acute and chronic diseases and may be influenced by nutritional deficits. We assessed the prognostic value of RDW regarding clinical outcomes and nutritional treatment response among medical inpatients at nutritional risk.

METHODS

This is a secondary analysis of EFFORT, a randomized, controlled, prospective, multicenter trial investigating the effects of nutritional support in patients at nutritional risk in eight Swiss hospitals. We examined the association between RDW and mortality in regression analysis.

RESULTS

Among 1,244 included patients (median age 75 years, 46.6 % female), high RDW (≥15 %) levels were found in 38 % of patients (n = 473) with a significant association of higher malnutrition risk [OR 1.48 (95%CI 1.1 to 1.98); p = 0.009]. Patients with high RDW had a more than doubling in short-term (30 days) mortality risk [adjusted HR 2.12 (95%CI 1.44 to 3.12); p < 0.001] and a signficant increase in long-term (5 years) mortality risk [adjusted HR 1.73 (95%CI 1.49 to 2.01); p < 0.001]. Among patients with high RDW, nutritional support reduced morality within 30 days [adjusted OR 0.56 (95%CI 0.33 to 0.96); p = 0.035], while the effect of the nutritional intervention in patients with low RDW was markedly smaller.

CONCLUSIONS

Among medical patients at nutritional risk, RDW correlated with several nutritional parameters and was a strong prognostic marker for adverse clinical outcomes at short- and long-term, respectively. Patients with high baseline RDW levels also showed a strong benefit from the nutritional intervention. Further research is needed to understand whether monitoring of RDW over time severs as a nutritional biomarker to assess effectiveness of nutritional treatment in the long run.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02517476.

Higher Preoperative Red Blood Cell Distribution Width Increases the Risk of Myocardial Injury After Noncardiac Surgery in Advanced-Age Patients: A Retrospective Cohort Study

Background

Myocardial injury after noncardiac surgery (MINS) has been associated with worse outcomes. The aim of our study was to investigate the relationship between higher red blood cell distribution width (RDW) and postoperative 30-day MINS among advanced-age patients.

Methods

This was a retrospective observational study including advanced-age patients (≥65 years old) who underwent noncardiac surgery between January 2017 and August 2019 at the First Medical Center of the Chinese People's Liberation Army General Hospital. Patients were divided into two groups according to the cutoff value identified the lowest risk using Restricted Cubic Splines (RCS) model. The primary outcome was the incidence of MINS within 30 days after surgery. The relationship between RDW and MINS was investigated by univariable and multi-variable logistic regression analysis. Propensity score (PS) analysis, including propensity score matching (PSM) and inverse probability treatment weighting (IPTW), as well as subgroup analysis were also conducted to identify the effect of RDW.

Results

The result of the RCS analysis showed that the risk of MINS in advanced-age patients increases when the baseline RDW is >12.8%. In the univariate analysis, baseline RDW >12.8% was a risk factor for postoperative MINS [odds ratio (OR)=2.11; 95% confidence interval (CI): 1.83-2.44; p<0.001]. After adjustment for all possible components, there was also a high risk of MINS for patients with elevated RDW [Adjusted OR (aOR)=1.43; 95% CI: 1.27-1.61; p<0.001). The relationship remained after PS analysis (aOR=1.24; 95% CI: 1.04-1.47; p=0.016 in PSM; aOR=1.23; 95% CI: 1.05-1.44; p=0.012 in IPTW, respectively). Significant differences between two groups were established in the incidence rate of postoperative cardiac complications and mortality.

Conclusion

Elevated preoperative RDW is significantly associated with an increased risk of MINS within postoperative 30 days.

Risk Factors for Acute Coronary Syndrome in Upper Gastrointestinal Bleeding Patients

Background

Upper gastrointestinal bleeding (UGIB) is a common critical disease with a certain fatality rate. Acute coronary syndrome (ACS), another critical ill condition, is a regular occurrence in the UGIB. We identified risk factors for ACS in UGIB.

Methods

676 patients diagnosed with UGIB were enrolled retrospectively. We assessed the occurrence of ACS in UGIB patients and identified the risk factors for ACS by logistic regression analysis and random forest analysis.

Results

After propensity score matching (PSM), the ACS group (n = 69) and non-ACS group (n = 276) were analyzed. Logistic regression analysis showed that syncope (P = 0.001), coronary heart disease history (P = 0.001), Glasgow Blatchford score (P ≤ 0.001), Rockall risk score (P = 0.004), red blood cell distribution width (RDW) (P ≤ 0.001), total bilirubin (TBil) (P = 0.046), fibrinogen (P ≤ 0.001), and hemoglobin (P = 0.001) had important roles in ACS patients. With Mean Decrease Gini (MDG) sequencing, fibrinogen, RDW, and hemoglobin were ranked the top three risk factors associated with ACS. In ROC analysis, fibrinogen (AUC = 0.841, 95% CI: 0.779-0.903) and RDW (AUC = 0.826, 95% CI: 0.769-0.883) obtained good discrimination performance. According to sensitivity > 80%, the pAUC of fibrinogen and RDW were 0.077 and 0.101, respectively, and there was no significant difference (P = 0.326). However, according to specificity > 80%, the pAUC of fibrinogen was higher than that of RDW (0.126 vs. 0.088, P = 0.018).

Conclusion

Fibrinogen and RDW were important risk factors for ACS in UGIB. Additionally, combination with coronary heart disease, syncope, hemoglobin, and TBil played important roles in the occurrence of ACS. Meanwhile, it was also noted that Rockall score and Glasgow Blatchford score should be performed to predict the risk.

Increased red cell distribution width predicts severity of drug-induced liver injury: a retrospective study

We used a retrospective study design to evaluated the predictive value of red cell distribution width (RDW) for drug-induced liver injury (DILI) severity in Chinese patients with liver biopsy to assist with early DILI management. We included 164 DILI patients with complete laboratory information and medical history. We compared outcomes of 36 patients with severe DILI with outcomes of a control group of 128 patients with mild-to-moderate DILI. Multivariate analyses of risk factors for severe liver injury in Chinese patients with DILI revealed an estimated adjusted odds ratio (AOR) (95% CI) of 4.938 (1.088–22.412) in patients with drinking. Risk for serious liver injury was also increased significantly in patients with dyslipidemia [AOR (95% CI) 3.926 (1.282–12.026)], higher serum total bile acid (TBA) levels [AOR (95% CI) 1.014 (1.009–1.020)] and higher RDW [AOR (95% CI) 1.582 (1.261–1.986)]. The result for area under the curve of 0.905 for TBA levels indicated this variable had high diagnostic performance for predicting DILI severity. Based on an area under the curve value of 0.855, RDW also had superior diagnostic performance in prediction of DILI severity. This performance was not significantly different compared with TBA and was superior compared with other variables, which had area under values ranging from poor to failure (0.527–0.714).The risk for severe DILI was associated with drinking, dyslipidemia, higher TBA levels and RDW values. This study found that RDW and TBA levels were predictors of DILI severity in Chinese patients.

Red Blood Cell Distribution Width-to-Platelet Ratio and Other Laboratory Indices Associated with Severity of Histological Hepatic Fibrosis in Patients with Autoimmune Hepatitis: A Retrospective Study at a Single Center

Background

This retrospective study at a single center aimed to evaluate the role of the red blood cell distribution width (RDW)-to-platelet ratio and other laboratory indices associated with the severity of histological hepatic fibrosis on liver biopsy in patients with autoimmune hepatitis (AIH).

Material/Methods

We retrospectively reviewed records from 2097 adult patients who had liver biopsies. Of these patients, data from 72 with AIH and 164 with drug-induced liver injury (DILI) with complete laboratory information and medical histories were included in the analysis.

Results

We found that compared with patients with DILI, patients with AIH had higher alkaline phosphatase, globulin, and total bile acid levels. Multivariate analyses of risk factors for AIH-associated advanced liver fibrosis in Chinese patients revealed an estimated adjusted odds ratio (AOR) (95% CI) of 1.609 (1.028–2.517) in patients with higher immunoglobulin A (IgA) levels. Patients with higher gamma-glutamyl transpeptidase (GGT)-to-platelet ratio (GPR) values had a significantly higher risk of serious liver fibrosis than patients with lower GPR values. Advanced fibrosis risk was higher in patients with higher RPR values than in patients with lower RPR values [AOR (95% CI): 25.507 (2.934–221.784)]. The result for area under the curve (0.821) analysis for lnRPR levels indicated this variable had high diagnostic performance for predicting advanced AIH-related fibrosis.

Conclusions

The degree of histological liver fibrosis in patients with AIH was significantly associated with an increased red blood cell distribution width-to-platelet ratio, GPR, and increased serum levels of IgA.

Red Cell Distribution Width as a Novel Predictor of Mortality and Complications After Primary Shoulder Arthroplasty

INTRODUCTION

Variability in red blood cell volume can occur in disease states and is quantified using a simple equation, yielding the relative distribution of width (RDW). Recent literature has correlated RDW with outcomes in many cardiac disease states, hip fractures, and even revision hip arthroplasty. The association with outcomes in total shoulder arthroplasty (TSA) is yet to be delineated. The purpose of this study was to investigate the possible relationship between preoperative RDW levels and mortality and other adverse outcomes after primary TSA.

METHODS

Patients who underwent primary TSA and had RDW values on record were identified in a national database. Patients were then grouped by RDW, and the incidence of complications was calculated for each group, including mortality within 1 year, periprosthetic infection within 1 year, acute venous thromboembolism within 30 days, and readmission to a hospital within 30 days. A threshold value of RDW for increased complications was established using receiver operator characteristic (ROC) curves.

RESULTS

Five thousand two hundred forty-five patients who underwent TSA with a recorded RDW were included in the study. An RDW cutoff of 16% was found to be significantly associated with mortality at 1 year (P < 0.0001), readmission (P < 0.0001), and infection (P = 0.013) on ROC analysis. When controlling for demographic and comorbidity values, a high RDW was markedly associated with a higher mortality rate (odds ratio 2.0, 95% confidence interval 18 to 2.2) and readmission rate (odds ratio 1.5, 95% confidence interval 1.3 to 1.8). A high RDW was not markedly associated with increased infection or venous thromboembolism rate in the multivariate analysis.

DISCUSSION

Increasing preoperative RDW is associated with increasing complication rates after TSA. This value can be used as an indirect, real-time preoperative predictor of adverse outcomes and most importantly one-year mortality and hospital readmission.

LEVEL OF EVIDENCE

III retrospective cohort study.

The Effect of Red Cell Distribution Width Admission Value on the Outcome of Patients with First-ever ST-elevation Myocardial Infarction in Basrah

Background Red cell distribution width (RDW) reflects the volumetric heterogeneity of red blood cells (RBCs) and has proven to be a prognostic predictor for cardiovascular (CV) morbidity and mortality in ST-elevation myocardial infarction (STEMI). The study aims to evaluate the effect of the RDW admission value on the outcome of patients with STEMI. Materials and methods This is a cross-sectional observational study on (207) patients with first-ever STEMI, grouped according to their baseline RDW and thrombolysis eligibility into two groups. We calculated the in-hospital Global Registry of Acute Coronary Events (GRACE) score within 48 hours of presentation. Results The study demonstrated the impact of RDW on the primary STEMI outcomes (left ventricular ejection fraction (LVEF%), ST-resolution, arrhythmias, and cardiovascular mortality risk). It was nearly a gender-matched study, with a mean RDW of 14.20±1.86%. RDW>14% and age≥65 years were the strongest statistically significant independent predictors of STEMI outcome with LVEF % < 45%, ST-resolution, and CV mortality regardless of thrombolysis. The thrombolysis offers a logical significant negative relation with CV mortality. At the same time, hypertension, diabetes mellitus (DM), and smoking may cause an additional mortality burden, especially in elderly patients with high RDW who are not eligible for thrombolysis. There was a significant association between high GRACE to high RDW, with excellent specificity and sensitivity in predicting CV outcome. Conclusion The RDW is a simple to acquire index, with a good prognostic prediction of major adverse cardiovascular events (MACEs) and CV mortality in the STEMI patients. It is excellent in predicting STEMI outcomes, especially the response to thrombolysis.

Red blood cell distribution width for predicting significant liver inflammation in patients with autoimmune hepatitis

BACKGROUND

Red blood cell distribution width (RDW) was reported to be associated with the severity of liver diseases. We aimed to investigate the association between RDW and severity of liver inflammation in autoimmune hepatitis (AIH).

PATIENTS AND METHODS

Ninety-two consecutive AIH patients who underwent liver biopsy during 2016-2017 were included. Liver histology was evaluated using the Scheuer scoring system. Logistic regression analysis was used to analyze the risk factors for significant inflammation. The diagnostic accuracy was evaluated by the area under the receiver operating characteristic curve.

RESULTS

The RDW level was higher in AIH patients with significant inflammation (14.6%, interquartile range: 13.2-16.3%) than in patients with mild inflammation (13.2%, interquartile range: 12.6-13.8%). The RDW level was correlated positively with the grades of liver inflammation (r=0.356, P < 0.001). The area under the receiver operating characteristic curve of RDW in predicting significant inflammation was 0.739 (95% confidential interval: 0.634-0.843, P < 0.001), with 67.80% sensitivity and 75.76% specificity. The diagnostic performance of RDW for significant inflammation was better than alanine aminotransferase (P = 0.003) and immunoglobulin G (P = 0.049). RDW (odds ratio = 1.702, P = 0.001) was identified as an independent predictor for significant inflammation by logistic multivariable analysis.

CONCLUSION

The RDW level was correlated positively with the severity of liver inflammation in AIH patients. RDW can be a promising indicator for predicting significant liver inflammation in AIH.

Red blood cell distribution width in pregnancy: a systematic review

Anisocytosis has been associated with the severity and prognosis of several acute and chronic diseases, as well as physiological conditions such as pregnancy. Anisocytosis is quantified by the red blood cell distribution width (RDW), expressed as the ratio, multiplied by 100, between the standard deviation (SD) of red blood cell volumes and the mean corpuscular volume, or as the SD of erythrocyte volumes (RDW-SD). The aim of the present review was to report the state of the art on the physiological values and the putative diagnostic and prognostic roles of RDW in complicated pregnancy. Literature research for articles published in the last ten years was conducted in Pubmed, Web of Science, ClinicalTrials.gov, and Scopus databases. Abstracts were independently screened by two investigators. If relevant, full articles were retrieved. References, in these articles, citing relevant reviews or original studies were also accessed to identify additional eligible studies. Any disagreement between the reviewers was resolved by a third investigator. A total of 28 studies were included in the review. These studies reported changes in RDW values during physiological pregnancy, and associations between the RDW and several pregnancy complications including anaemia, preeclampsia, gestational diabetes, and recurrent miscarriage. This review provides background information for establishing physiological and pathological RDW values in pregnancy for diagnostic and prognostic use in clinical practice.

Red Cell Distribution Width: An Unacknowledged Predictor of Mortality and Adverse Outcomes Following Revision Arthroplasty

BACKGROUND

Revision total joint arthroplasties (TJAs) have been empirically associated with significant postoperative morbidity and mortality. Red blood cell distribution width (RDW), a frequently measured hematological parameter, has been shown to predict mortality in hip fracture patients. However, its utility in risk-stratifying patients before revision TJA remains unknown. The aim of this study was to investigate the possible relationship between preoperative RDW levels and outcome of revision arthroplasty in terms of mortality, adverse outcomes, and length of hospital stay.

METHODS

A single-institution retrospective study was conducted on 4633 patients who underwent revision TJA (3289 hips and 1344 knees) between 2000 and September 2016. Of those, 656 (14.1%) surgeries were performed due to periprosthetic joint infection, and 3977 (85.9%) were aseptic revisions. The association between preoperative RDW and various outcomes, including 1-year mortality, in-hospital medical complications, length of hospital stay, and 90-day all-cause readmission, was examined.

RESULTS

The average age of patients in the cohort was 65.4 ± 12.9 years. The average Charlson comorbidity index was 0.6 (standard deviation = 1.0), with 691 patients (14.9%) having 2 or more comorbidities. Mean preoperative RDW level was 14.4% (standard deviation = 1.8). After adjusting for covariates, higher RDW levels were statistically significantly associated with mortality (adjusted odds ratio [OR], 1.25; 95% confidence interval [CI], 1.13-1.39; P < .001), any in-hospital medical complications (adjusted OR, 1.12; 95% CI, 1.07-1.18; P < .001), and readmission (adjusted OR, 1.07; 95% CI, 1.02-1.13; P < .001).

CONCLUSION

Higher levels of preoperative RDW appeared to be associated with less optimal outcomes after revision TJA. Adult reconstruction orthopedic surgeons should be aware of this predictive factor and exercise caution with TJA revision patients with high values of preoperative RDW. RDW could be included in the routine perioperative workup and used to counsel patients on their postoperative risk.

Combined value of red blood cell distribution width and global registry of acute coronary events risk score on predicting long-term major adverse cardiac events in STEMI patients undergoing primary PCI

The combined value of RDW and GRACE risk score for cardiovascular prognosis in ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) has not been fully investigated. This study was designed to explore the combined value of RDW and GRACE risk score on predicting long-term major adverse cardiac event (Mace) in STEMI patients undergoing primary PCI. This study included 390 STEMI patients. The primary endpoint at the (33.5 ± 7.1) months follow-up was composed of cardiac death and nonfatal myocardial infarction. The relationship between clinical parameters and clinical outcomes was evaluated using Cox regression model and receiver operating characteristic (ROC) analysis. Mace occurred in 126 (32.3%) patients including 54 (13.8%) cardiac deaths and 72 (18.5%) nonfatal myocardial infarctions. Patients in Mace group had significantly higher RDW and GRACE score than the patients in non-Mace group. According to the Cox model, RDW and GRACE score were the most important independent predictors of Mace and cardiac death. The best cut-off value for RDW to predict the occurrence of primary events was 13.25% (AUC = 0.694, 95% CI:0.639–0.750, P < 0.001) and that for GRACE score was 119.5 (AUC = 0.721, 95% CI:0.666–0.777, P < 0.001). The combination of RDW and GRACE score were more valuable (AUC = 0.775, 95% CI: 0.727–0.824, P < 0.001). Kaplan–Meier analysis provided significant prognostic information with the highest risk for cardiac death (Log-Rank χ² = 24.684, P < 0.001) in group with both high RDW (> 13.25%) and high GRACE score (> 119.5). The combination of RDW level and GRACE score may be valuable and simple independent predictors of Mace and cardiac death in STEMI patients undergoing primary PCI. They may be useful tools for risk stratification and may indicate long-term clinical outcomes.

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

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

[Regression analysis of red cell distribution width and mean platelet volume in patients with acute myocardial infarction]

OBJECTIVE

To investigate clinical implications of changes in red cell distribution width (RDW) and mean platelet volume (MPV) in patients with acute myocardial infarction.

METHODS

A total of 127 patients (90 men and 37 women) were enrolled in this analysis, including 66 with acute myocardial infarction (AMI) and 61 with unstable angina (UA). The patients' baseline demographic and clinical data were compared between the two groups including age, hypertension, diabetes, smoking, BMI, blood biochemical profiles, cardiac functions and platelet and red blood cell parameters. The patients were further divided into subgroups according to the RDW 50% cumulative frequency, and the MPV, P-LCR, hsCRP, NT-proBNP, RBC, Dimer and MCV were compared. The correlations between platelet and erythrocyte test results were evaluated in both the AMI and UA patients. Regression analysis was performed to identify the factors affecting the RDW in the AMI group and a regression model was established.

RESULTS

The platelet and red blood cell test results, P-LCR, MPV, and RDW differed significantly between AMI and UA groups (P<0.01 or 0.05). Correlation analysis showed a significant positive correlation between RDW and MPV in AMI group (r=0.34, P<0.01). Between the subgroups with different RDW 50% cumulative frequencies, MPV, P-LCR, hsCRP, D-Dimer, and NT-proBNP all differed significantly (P<0.05 or 0.01). In AMI group, with RDW as the dependent variable, we established a multivariate regression model of RDW=0.19MPV+10.83.

CONCLUSION

RDW and MPV are closely correlated in patients with AMI. In multiple regression analysis, MPV can explain the changes in RDW in patients with AMI.

Prognostic value of red blood cell distribution width in hepatocellular carcinoma

Red blood cell distribution width (RDW) is a simple, inexpensive, routinely measured and automatically reported blood test parameter, which reflects the degree of anisocytosis of red blood cells in peripheral blood. RDW was found to be associated with and retain clinical significance for assessing disease severity and outcomes in a number of hematological and solid malignancies. Motley of interacting clinical and biochemical factors have an impact on the red cell population biology. Malignancies per se can act as a causative factor, or anisocytosis may develop as a result of chronic inflammation. RDW has also been shown to be affected by nutritional status, which is typically deranged in malignancies. RDW is shown to be a clinically useful marker of disease severity and level of fibrosis in liver cirrhosis of various causes such as hepatitis B, hepatitis C and non-alcoholic fatty liver disease. Whether liver cirrhosis patients with higher RDW are at increased risk of hepatocellular cancer is yet to be determined, but several lines of evidence confirm that RDW has clinical significance in hepatocellular carcinoma (HCC). In this review, we specifically discuss the current literature about the association between RDW and HCC. The available evidences were summarized and the potential underlying mechanisms were analyzed.

An overall and dose-response meta-analysis of red blood cell distribution width and CVD outcomes

Red blood cell distribution width (RDW) is the coefficient of variation of red blood cell size, considered to be associated with cardiovascular disease (CVD). This study aimed to comprehensively synthesize previous studies on RDW and CVD outcomes through an overall and dose-response meta-analysis. PubMed, Embase and Web of Science were searched systematically for English and Chinese language publications up to November 30, 2015. We extracted data from publications matching our inclusion criteria for calculating pooled hazard ratio (HR), which was used to assess prognostic impact of RDW on CVD. Twenty-seven articles, consisting of 28 studies and 102,689 participants (mean age 63.9 years, 63,703 males/36,846 females, 2,140 gender-unmentioned subjects) were included in the present meta-analysis. The pooled HRs are 1.12 (95% CI = 1.09-1.15) for the association of all-cause mortality (ACM) per 1% increase of RDW, 1.12(95% CI = 1.08-1.17) for major adverse cardiac events (MACEs) per 1% increase of RDW. A dose-response curve relating RDW increase to its effect on CVD outcomes was established (p_curve < 0.001). For every 1-unit increase of RDW, there is an increased risk of occurrence of ACM (pooled HR = 1.03, 95% CI = 1.02-1.04) and MACEs (pooled HR = 1.04, 95% CI = 1.01-1.06). This study indicates RDW may be a prognostic indicator for CVD outcomes.

Association of standard clinical and laboratory variables with red blood cell distribution width

BACKGROUND

Red blood cell distribution width (RDW) strongly predicts clinical outcomes among patients with coronary disease and heart failure. The factors underpinning this association are unknown.

METHODS

In 6,447 individuals enrolled in the Measurement to Understand the Reclassification of Disease of Cabarrus/Kannapolis (MURDOCK) Study who had undergone coronary angiography between 2001 and 2007, we used Cox proportional hazards modeling to examine the adjusted association between RDW and death, and death or myocardial infarction (MI). Multiple linear regression using the R(2) model selection method was then used to identify clinical factors associated with variation in RDW.

RESULTS

Median follow-up was 4.2 (interquartile range 2.3-5.9) years, and the median RDW was 13.5% (interquartile range 12.9%-14.3%, clinical laboratory reference range 11.5%-14.5%). Red blood cell distribution width was independently associated with death (adjusted hazard ratio 1.13 per 1% increase in RDW, 95% CI 1.09-1.17), and death or MI (adjusted hazard ratio 1.12, 95% CI 1.08-1.16). Twenty-seven clinical characteristics and laboratory measures were assessed in the multivariable linear regression model; a final model containing 18 variables explained only 21% of the variation in RDW.

CONCLUSIONS

Although strongly associated with death and death or MI, only one-fifth of the variation in RDW was explained by routinely assessed clinical characteristics and laboratory measures. Understanding the latent factors that explain variation in RDW may provide insight into its strong association with risk and identify novel targets to mitigate that risk.

The Prognostic Role of Red Blood Cell Distribution Width in Coronary Artery Disease: A Review of the Pathophysiology

Red blood cell distribution width (RDW) is a measure of red blood cell volume variations (anisocytosis) and is reported as part of a standard complete blood count. In recent years, numerous studies have noted the importance of RDW as a predictor of poor clinical outcomes in the settings of various diseases, including coronary artery disease (CAD). In this paper, we discuss the prognostic value of RDW in CAD and describe the pathophysiological connection between RDW and acute coronary syndrome. In our opinion, the negative prognostic effects of elevated RDW levels may be attributed to the adverse effects of independent risk factors such as inflammation, oxidative stress, and vitamin D₃ and iron deficiency on bone marrow function (erythropoiesis). Elevated RDW values may reflect the intensity of these phenomena and their unfavorable impacts on bone marrow erythropoiesis. Furthermore, decreased red blood cell deformability among patients with higher RDW values impairs blood flow through the microcirculation, resulting in the diminution of oxygen supply at the tissue level, particularly among patients suffering from myocardial infarction treated with urgent revascularization.

Inflammatory markers in ST-elevation acute myocardial infarction

After acute myocardial infarction, ventricular remodeling is characterized by changes at the molecular, structural, geometrical and functional level that determine progression to heart failure. Inflammation plays a key role in wound healing and scar formation, affecting ventricular remodeling. Several, rather different, components of the inflammatory response were studied as biomarkers in ST-elevation acute myocardial infarction. Widely available and inexpensive tests, such as leukocyte count at admission, as well as more sophisticated immunoassays provide powerful predictors of adverse outcome in patients with ST-elevation acute myocardial infarction. We review the value of inflammatory markers in ST-elevation acute myocardial infarction and their association with ventricular remodeling, heart failure and sudden death. In conclusion, the use of these biomarkers may identify subjects at greater risk of adverse events and perhaps provide an insight into the mechanisms of disease progression.

Red blood cell distribution width: A simple parameter with multiple clinical applications

The red blood cell distribution width (RDW) is a simple and inexpensive parameter, which reflects the degree of heterogeneity of erythrocyte volume (conventionally known as anisocytosis), and is traditionally used in laboratory hematology for differential diagnosis of anemias. Nonetheless, recent evidence attests that anisocytosis is commonplace in human disorders such as cardiovascular disease, venous thromboembolism, cancer, diabetes, community-acquired pneumonia, chronic obstructive pulmonary disease, liver and kidney failure, as well as in other acute or chronic conditions. Despite some demographic and analytical issues related to the routine assessment that may impair its clinical usefulness, an increased RDW has a high negative predictive value for diagnosing a variety of disorders, but also conveys important information for short- and long-term prognosis. Even more importantly, the value of RDW is now being regarded as a strong and independent risk factor for death in the general population. Although it has not been definitely established whether an increased value of RDW is a risk factor or should only be considered an epiphenomenon of an underlying biological and metabolic imbalance, it seems reasonable to suggest that the assessment of this parameter should be broadened far beyond the differential diagnosis of anemias. An increased RDW mirrors a profound deregulation of erythrocyte homeostasis involving both impaired erythropoiesis and abnormal red blood cell survival, which may be attributed to a variety of underlying metabolic abnormalities such as shortening of telomere length, oxidative stress, inflammation, poor nutritional status, dyslipidemia, hypertension, erythrocyte fragmentation and alteration of erythropoietin function. As such, the aim of this article is to provide general information about RDW and its routine assessment, to review the most relevant implications in health and disease and give some insights about its potential clinical applications.

The role of red blood cell distribution width in mortality and cardiovascular risk among patients with coronary artery diseases: a systematic review and meta-analysis

BACKGROUND

Red cell distribution width (RDW) might be a novel biomarker that reflects multiple physiological impairments related to atherosclerosis and coronary artery diseases (CAD). We conducted this systematic review and meta-analysis to evaluate the association of RDW between all-cause mortality and fatal/non-fatal cardiovascular disease (CVD) events in CAD patients.

METHODS

Relevant studies were searched and identified in the MEDLINE and EMBASE databases. English-language prospective studies that reported risk estimates for RDW and mortality/CVD events were included. Data were extracted regarding the characteristics and clinical outcomes, and a quality assessment was conducted. Results were extracted for the highest versus lowest RDW level, and meta-analyses were carried out using random effects models.

RESULTS

We identified 22 studies enrolling 80,216 participants. The study duration ranged between 1 month and 23 years. Of the 15 studies that were included in the meta-analysis, higher RDW indicated a significant increased risk for all-cause mortality in CAD patients: pooled risk ratio (RR) 2.20 (95% CI, 1.42-3.39; P<0.0004). The results for fatal, non-fatal and fatal/non-fatal events were: pooled RR 1.80 (95% CI, 1.35-2.41; P<0.0001), RR 1.86 (95% CI, 1.50-2.31; P<0.00001) and RR 2.13 (95% CI, 1.20-3.77; P=0.01). Heterogeneity was moderately present; however, sensitivity analyses for follow-up duration, CAD subtype, or RDW as dichotomous values showed similar results.

CONCLUSIONS

The meta-analysis indicates that higher RDW levels are associated with increased risk of mortality and CVD events in patients with established CAD.

Red cell distribution width is associated with incident myocardial infarction in a general population: the Tromsø Study

Background

Red cell distribution width (RDW), a measure of the variability in size of circulating erythrocytes, is associated with mortality and adverse outcome in selected populations with cardiovascular disease. It is scarcely known whether RDW is associated with incident myocardial infarction (MI). We aimed to investigate whether RDW was associated with risk of first‐ever MI in a large cohort study with participants recruited from a general population.

Methods and Results

Baseline characteristics, including RDW, were collected for 25 612 participants in the Tromsø Study in 1994–1995. Incident MI during follow‐up was registered from inclusion through December 31, 2010. Cox regression models were used to calculate hazard ratios with 95% confidence intervals for MI, adjusted for age, sex, body mass index, smoking, hemoglobin, white blood cells, platelets, and other traditional cardiovascular risk factors. A total of 1779 participants experienced a first‐ever MI during a median follow‐up time of 15.8 years. There was a linear association between RDW and risk of MI, for which a 1% increment in RDW was associated with a 13% increased risk (hazard ratio 1.13; 95% CI, 1.07 to 1.19). Participants with RDW above the 95th percentile had 71% higher risk of MI compared with those with RDW in the lowest quintile (hazard ratio 1.71; 95% CI, 1.34 to 2.20). All effect estimates were essentially similar after exclusion of participants with anemia (n=1297) from the analyses.

Conclusion

RDW is associated with incident MI in a general population independent of anemia and cardiovascular risk factors.

Predicting readmission or death after acute ST-elevation myocardial infarction

BACKGROUND

Risk factors for emergent readmissions or death after acute myocardial infarction (AMI) are important in identifying patients at risk for major adverse events. However, there has been limited investigation conducted of prospective clinical registries to determine relevant risk factors.

HYPOTHESIS

We hypothesize 30-day readmission or death could be predicted using patient, procedural, and process factors.

METHODS

Patients presenting with ST-elevation myocardial infarction (STEMI) from 2006 to 2011 were prospectively enrolled in a STEMI registry (1271 patients). Thirty-day readmission was ascertained by administrative claims data. Death was determined by linking to the Social Security Death Master File. Univariate and stepwise multivariate logistic regression was conducted with Hosmer-Lemeshow goodness-of-fit statistics for model calibration and receiver operating characteristic (ROC) curve for model discrimination.

RESULTS

The combined end point of 30-day readmission or postdischarge death included 135 patients (10.6%), including 109 emergent readmissions and 26 deaths. Factors associated with an increase risk of 30-day readmission or postdischarge death included age ≥ 80 years, diabetes, chest pain or cardiac arrest at presentation, and 3-vessel disease found at initial angiography. Factors associated with a decreased risk of 30-day readmission or postdischarge death included transfer to the catheterization lab from another emergency department, clopidogrel given during the procedure hypercholesterolemia, and receiving aspirin, β-blockers, and angiotensin-converting enzyme or angiotensin receptor blocker inhibitors at discharge. Index admission outcomes indicative of readmission or death postdischarge only included a new diagnosis of congestive heart failure. The model discriminated well with an ROC of 0.71 (95% confidence interval: 0.66-0.76).

CONCLUSIONS

Prehospitalization factors are overlooked and are important factors to incorporate in routine risk prediction models for readmission or death within 30 days following an AMI.