Red cell distribution width for prognosis in patients with pulmonary embolism: A systematic review and meta‐analysis

Association between red blood cell distribution width and 30-day mortality in critically ill septic patients: a propensity score-matched study

BACKGROUND

Sepsis is the leading cause of death worldwide, and a number of biomarkers have been developed for early mortality risk stratification. Red blood cell distribution width (RDW) is a routinely available hematological data and has been found to be associated with mortality in a number of diseases; therefore, we aim to address the association between RDW and mortality in critically ill patients with sepsis.

METHODS

We analyzed data of critically ill adult patients with sepsis on the TriNetX platform, excluding those with hematologic malignancies, thalassemia, and iron deficiency anemia. Propensity score-matching (PSM) (1:1) was used to mitigate confounding effects, and hazard ratio (HR) with 95% confidence (CI) was calculated to determine the association between RDW and 30-day mortality. We further conducted sensitivity analyses through using distinct cut-points of RDW and severities of sepsis.

RESULTS

A total of 256,387 critically ill septic patients were included in the analysis, and 40.0% of them had RDW equal to or higher than 16%. After PSM, we found that high RDW was associated with an increased 30-day mortality rate (HR: 1.887, 95% CI 1.847-1.928). The associations were consistent using distinct cut-points of RDW, with the strength of association using cut-points of 12%, 14%, 16%, 18% and 20% were 2.098, 2.204, 1.887, 1.809 and 1.932, respectively. Furthermore, we found consistent associations among critically ill septic patients with distinct severities, with the association among those with shock, receiving mechanical ventilation, bacteremia and requirement of hemodialysis being 1.731, 1.735, 2.380 and 1.979, respectively.

CONCLUSION

We found that RDW was associated with 30-day mortality in critically ill septic patients, underscoring the potential as a prognostic marker in sepsis. More studies are needed to explore the underlying mechanisms.

Decoding Pulmonary Embolism: Pathophysiology, Diagnosis, and Treatment

Pulmonary Embolism (PE) is a life-threatening condition initiated by the presence of blood clots in the pulmonary arteries, leading to severe morbidity and mortality. Underlying mechanisms involve endothelial dysfunction, including impaired blood flow regulation, a pro-thrombotic state, inflammation, heightened oxidative stress, and altered vascular remodeling. These mechanisms contribute to vascular diseases stemming from PE, such as recurrent thromboembolism, chronic thromboembolic pulmonary hypertension, post-thrombotic syndrome, right heart failure, and cardiogenic shock. Detailing key risk factors and utilizing hemodynamic stability-based categorization, the review aims for precise risk stratification by applying established diagnostic tools and scoring systems. This article explores both conventional and emerging biomarkers as potential diagnostic tools. Additionally, by synthesizing existing knowledge, it provides a comprehensive outlook of the current enhanced PE management and preventive strategies. The conclusion underscores the need for future research to improve diagnostic accuracy and therapeutic effectiveness in PE.

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

Objective

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

Methods

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

Results

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

Conclusion

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

Red blood cell distribution width as a predictor of mortality and poor functional outcome after acute ischemic stroke: a meta-analysis and meta-regression

BACKGROUND

This study aimed to review evidence on the ability of red cell distribution width (RDW) to predict mortality and poor functional outcomes after acute ischemic stroke (AIS).

METHODS

Databases of PubMed, CENTRAL, Scopus, Embase, and Web of Science were searched online from inception to 25th Jul 2023 for all studies reporting the association between RDW and outcomes as adjusted ratios. A random-effects meta-analysis was done. Meta-regression was conducted using multiple moderators.

RESULTS

15 studies with 14,968 patients were included. Meta-analysis found that RDW, both as a categorical variable (OR: 2.10 95% CI: 1.74, 2.55 I2 = 42%) and continuous variable OR: 1.16 95% CI: 1.05, 1.28 I2 = 64%) was a significant predictor of mortality after AIS. Age and number of hypertensives were found to be significant moderators in the meta-regression. Also, high RDW, as a categorical variable (OR: 1.68 95% CI: 1.20, 2.35 I2 = 84%), was associated with significantly higher odds of poor functional outcomes after AIS, but not as a continuous variable (OR: 1.07 95% CI: 0.99, 1.16 I2 = 61%). Meta-regression showed that the association was stronger in small sample-sized studies.

CONCLUSION

RDW can be a useful, readily available, and cost-effective biomarker to rapidly stratify AIS patients at risk of poor outcomes. High RDW was consistently associated with an increased risk of mortality after AIS, however, its ability to predict poor functional outcomes needs to be verified by further studies.

Association between red blood cell distribution width and psoriasis among the US adults

Introduction

The association between red blood cell distribution width (RDW) and psoriasis among the US adults is still unknown. We aimed to assess whether RDW is associated with psoriasis in the US adults.

Method

We conducted a cross-sectional study consisting of 14,089 participants from National Health and Nutrition Examination Survey (NHANES) 2009-2014. Psoriasis status were assessed by self-reported questionnaire. We evaluated the association between RDW and risk of psoriasis using multivariate regression models. Subgroup and interaction analysis were performed.

Results

The higher RDW level was associated with an increased risk of psoriasis (OR = 1.10 [95% CI, 1.01, 1.19]; p = 0.025) after adjusting for confounders in female. However, there is no significant association between RDW and risk of psoriasis among male (OR = 0.99 [95% CI, 0.87, 1.15]; p = 0.992). Subgroup and interaction analysis found that the strongest positive association mainly exists in female participants with BMD greater than 29.9 kg/m2 (OR = 1.20 [95% CI, 1.09, 1.32], Pint = 0.004).

Discussion

In conclusion, we found that increased RDW levels were associated with an increased risk of psoriasis in females, which could provide clinicians with auxiliary data for the early diagnosis of psoriasis.

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.

Predictive Value of Red Cell Distribution Width in the Diagnosis of Peripherally Inserted Central Catheter (PICC)-Related Thrombosis Among Cancer Patients

Purpose

This study aimed to investigate the predictive value of red cell distribution width (RDW) in patients with peripherally inserted central catheter (PICC)-related thrombosis.

Patients and methods

This was a case‒control study. A total of 98 cancer patients undergoing PICC placement from January 2017 to December 2019 at the ICU Venous Access Center of Peking University Cancer Hospital were retrospectively analyzed. These included 47 cases in the thrombosis group and 51 cases in the nonthrombosis group according to the occurrence of PICC-related thrombosis within 90 days after the PICC procedure.

Results

a) RDW was significantly higher in the thrombosis group (15.98±1.93) than in the nonthrombosis group (13.98±1.09). Additionally, the number of smoking histories in the thrombosis group (18, 38.30%) was significantly higher than that in the nonthrombosis group (5, 9.80%). b) Logistic regression analysis indicated that RDW and smoking history were independent risk factors for PICC-related thrombosis (OR: 3.028, P<0.001; OR: 5.640, P=0.023). c) The area under the receiver operating characteristic (ROC) curve of the combination of RDW and smoking history was 86.8%, and the sensitivity and specificity for predicting thrombosis after PICC were 85.1% and 80%, respectively. d) Cox regression analysis revealed that RDW and smoking history were independent risk factors for PICC-related thrombosis (p<0.001). e) Results from Kaplan‒Meier analysis showed that incidence of PICC-related thrombosis in patients with RDW less than 14.75% is significantly lower than those with RDW 14.75% and above (p<0.001). e) Baseline RDW was not different between the two groups (P>0.05), ΔRDW was significantly different between the two groups (p<0.001).

Conclusion

The combined use of RDW and smoking history has early evaluation and predictive value in the diagnosis of PICC-related thrombosis.

Is red cell distribution width a prognostic factor in patients with breast cancer? A meta-analysis

Purpose

The current study aimed to investigate whether red blood cell distribution width (RDW) can predict the prognosis of patients with breast cancer (BC).

Methods

We searched four databases, including PubMed, Embase, Cochrane Library databases, and CNKI, from inception to Jun 13, 2022. The primary outcome was overall survival (OS), and the secondary outcome was disease-free survival (DFS). A subgroup analysis was conducted based on different treatments. This meta-analysis was performed with RevMan 5.3 (The Cochrane Collaboration, London, United Kingdom).

Results

A total of seven studies including 4,884 BC patients were identified. The high RDW group had a larger tumor size (OR = 2.12, 95% CI = 1.67 to 2.68, P < 0.01), higher proportions of advanced stage tumors (OR = 1.77, 95% CI = 1.38 to 2.27, P < 0.01), more lymph node metastases (OR = 2.00, 95% CI = 1.58 to 2.51, P < 0.01) and lower HER-2 expression (OR = 0.76, 95% CI = 0.61 to 0.95, P = 0.02). For prognosis, after pooling all the data, we found that the high RDW group was associated with worse OS (HR = 2.12, 95% CI = 1.47 to 3.08, P < 0.01) and DFS (HR = 1.77, 95% CI = 1.32 to 2.37, P < 0.01). The subgroup analysis found that RDW had prognostic significance but only for surgery-only patients (HR = 2.41, 95% CI = 1.67 to 3.49, P < 0.01).

Conclusion

High RDW was associated with worse OS and DFS. Therefore, RDW was a simple predictive factor for the prognosis of BC patients.

Predictors of rebleeding in patients with acute non-variceal upper gastrointestinal bleeding

BACKGROUND

There is a risk of rebleeding after acute non-variceal upper gastrointestinal bleeding (ANVUGIB), and rebleeding increases the risk of poor prognosis. At present, there is no effective predictive method for such rebleeding. The changes of red blood cell distribution width as well as hemoglobin and gastrin levels are all related to bleeding diseases, which can provide a reference for clinical improvement of relevant mechanisms and prediction of bleeding.

AIM

To investigate the relationship of the red blood cell distribution width (RDW), hemoglobin (Hb), and gastrin (GAS) with Glasgow-Blatchford score (GBS) and AIMS65 score in patients with ANVUGIB and to explore their predictive value for rebleeding.

METHODS

A prospective cohort study was conducted on 122 ANVUGIB patients admitted to our hospital from August 2018 to February 2021, and they were divided into either a rebleeding group (n = 31) or a no-rebleeding group (n = 91) according to whether rebleeding occurred 7 d after onset. Baseline data, RDW, Hb, GAS, GBS score, and AIMS65 score were compared between the two groups. Pearson correlation analysis was performed to explore the relationship of each index with GBS and AIMS65 scores, and multi-factor logistic regression analysis was performed to identify the influencing factors of rebleeding. The receiver operating characteristic (ROC) curve and the area under the curve (AUC) were used to analyze the value of each index in predicting rebleeding, and to compare the incidence of rebleeding in patients with different levels of each index.

RESULTS

The proportion of patients with gastrointestinal bleeding in the rebleeding group was higher than that of the no-rebleeding group. The RDW, GAS, and GBS and AIMS65 scores were higher and Hb was lower in the rebleeding group than in the no-rebleeding group (P < 0.05). RDW and GAS were positively correlated with GBS and AIMS65 scores, and Hb was negatively correlated with GBS and AIMS65 scores (P < 0.05). Multivariate logistic regression analysis showed that after controlling for past gastrointestinal bleeding, GBS, and AIMS65 score, RDW, Hb, and GAS were still influencing factors of rebleeding (P < 0.05). The performance of RDW and Hb combined with GAS for predicting rebleeding (AUC = 0.850) was better than that of RDW (0.721), Hb (0.721), or GAS (0.806) alone. The rebleeding rate in patients with high levels of RDW and GAS was higher than that of patients with low levels, but patients with high levels of Hb had a lower rebleeding rate than those with low levels (P < 0.05).

CONCLUSION

RDW, Hb, and GAS are related to the risk of disease and rebleeding in patients with ANVUGIB. Combined detection of them may be a reliable method to assess the risk of disease and predict rebleeding.

Evaluation of hematological parameters related to systemic inflammation in acute and subacute/chronic low back pain

Aim: To compare the hematological parameters associated with systemic inflammation between acute and subacute/chronic nonspecific low back pain and to evaluate their diagnostic roles in relation to chronicity in low back pain. Materials & methods: This retrospective case-control study included 150 participants aged 18-65 years with acute nonspecific low back pain, 150 with subacute/chronic nonspecific low back pain, 150 as the control group. Results: Red cell distribution width was significantly higher in the subacute/chronic pain group compared with the acute pain group (p = 0.003), and had a poor diagnostic value for chronicity (cutoff: 11.95, p = 0.003). There were no significant differences in terms of other parameters (p > 0.05). Conclusion: Red cell distribution width has a poor diagnostic value for chronicity in nonspecific low back pain.

Research progress on biomarkers of pulmonary embolism

OBJECTIVES

To present a review on the traditional and new biomarkers of pulmonary embolism (PE).

DATA SOURCE

A systematic search has been carried out using keywords as PE, biomarker, diagnosis and risk stratification.

RESULTS

The results of this work have been structured into three parts: first, conventional biomarkers for vascular, cardiac and inflammation, including static markers and dynamic markers for measuring the time course; next, a review of new biomarkers in recent years, such as RNAs and markers obtained through proteomics and mass spectrometry; finally, use of new detection methods to directly detect the activity of existing markers, such as the determination of coagulation factor II and plasmin activities based on the proteolytic activation of an engineered zymogen.

CONCLUSIONS

This work summarized the characteristics of current traditional biomarkers for clinical diagnosis and risk stratification of PE, as well as a series of newly discovered biomarkers obtained through various clinical experimental methods.