The Prognostic Significance of Red Cell Distribution Width in Cardiac Surgery: A Systematic Review and Meta-Analysis

The association between elevated preoperative red cell distribution width and worsening kidney function after noncardiac operation. A propensity score and competing risk weighted retrospective cohort study

Background

Elevated red cell distribution width (RDW) is associated with increased postoperative mortality, but less is known about kidney outcomes. This study investigated the association between elevated preoperative RDW and postoperative worsening of long-term kidney function and incidence of acute kidney injury.

Methods

This retrospective cohort study included patients ≥18 yr undergoing noncardiac operation at Landspitali-The National University Hospital of Iceland between 2005 and 2018. Outcomes were compared between groups with elevated preoperative RDW (13.3-14.0%, 14.0-14.7%, 14.7-15.8%) and a propensity score-matched cohort (RDW ≤13.3%) using Fine-Gray competing risk regression analysis, with death as a competing event. The primary outcome was time to worsening of at least one estimated glomerular filtration rate (eGFR) category sustained for 3 months. Secondary outcomes were acute kidney injury, length of hospital stay, and 30-day readmission rate.

Results

Out of 63 056 operations included in this study, 55 724 were available for propensity score-matched analysis. The hazard of long-term eGFR worsening was higher for patients with RDW between 14.0% and 14.7%: hazard ratio (HR) 1.23 (95% confidence interval [CI] 1.13-1.35), 14.7% and 15.8%: HR 1.20 (95% CI 1.07-1.34), and >15.8%: HR 1.16 (95% CI 1.00-1.34) compared with matched controls (RDW <13.3%), adjusted for death as a competing event. For secondary outcomes there was no difference in acute kidney injury, but increased risk of readmission for patients with RDW of 14.0-14.7% (9.8% vs 8.5%, P=0.01), 14.7-15.8% (12.2% vs 10.1%, P=0.001), and >15.8% (14.9% vs 11.4%, P<0.001).

Conclusions

Elevated preoperative RDW was associated with long-term worsening of eGFR category after operation.

Modified Early Warning Score (MEWS) combined with biomarkers in predicting 7-day mortality in traumatic brain injury patients in the emergency department: a retrospective cohort study

Background

Traumatic brain injury (TBI) is a leading cause of injury-related disability and death globally, which negatively affects individuals, families, and society. Predicting the risk for mortality among TBI patients is crucial in guiding further timely and effective treatment plans. Both the standard risk assessment tools and blood-based biomarkers are helpful in predicting outcomes among TBI patients. However, no studies have compared the predicting performance of the individual and combined indicators from the two major types.

Aim

This study aimed to compare the Modified Early Warning Score (MEWS), Red blood cell distribution width (RDW), and creatine in predicting 7-day mortality among TBI patients.

Methods

A retrospective study was conducted in the emergency department of the First People's Hospital of Changde, China, from January 1, 2023, to June 30, 2023. Data of 1,701 patients with TBI were obtained from the hospital's electronic medical records. A logistic regression model was used to determine independent factors influencing 7-day mortality. The area under the curve (AUC) of the receiver operating characteristic curve (ROC) was calculated to compare the individual and combined effects of MEWS, RDW, and creatine in predicting 7-day mortality based on bootstrap resampling (500 times).

Results

Among the 1,701 patients, 225 died, with a mortality rate of 13.23%. The multivariate analysis showed that the type of TBI lesion, MEWS, SBP, DBP, MAP, SpO2, temperature, RDW, and creatine were significantly associated with 7-day mortality. MEWS (AUC: 0.843) performed better than RDW (AUC: 0.785) and creatine (AUC: 0.797) in predicting 7-day mortality. MEWS+RDW (AUC: 0.898) performed better than MEWS+creatine (AUC: 0.875) and RDW+ creatine (AUC: 0.822) in predicting 7-day mortality. The combination of all three indicators, MEWS+RDW+creatine, showed the best predicting performance (AUC: 0.906).

Conclusion

MEWS performed best in predicting the 7-day mortality of TBI patients, and its predicting performance was improved when combined with blood-based biomarkers such as RDW and creatine. Our findings provide preliminary evidence supporting the combination of MEWS with blood-based biomarkers as a new method for predicting 7-day mortality in patients with TBI.

Prediction of the need for surgery in patients with unruptured abdominal aortic aneurysm based on SOFA score

OBJECTIVE

This retrospective study aimed to explore the association and clinical value of sequential organ failure assessment (SOFA) score on the predictors of adverse events in patients with unruptured abdominal aortic aneurysms (AAA).

METHODS

A total of 322 patients from Medical Information Mart for Intensive Care IV database were enrolled. Logistic regression was conducted to explore the association between SOFA and primary outcome (need for surgery, NFS). Receiver operating characteristic (ROC) and nomogram analyses were used to assess its performance for predicting NFS. We also explored the association and clinical value of SOFA on secondary outcomes including hospital length of stay (LOS), ICU-LOS, and in-hospital mortality by linear and logistic regression analyses, generalized additive model, ROC, and decision curve analysis.

RESULTS

Totally 291 patients underwent the surgery. High SOFA score significantly correlated with NFS both in crude and adjusted models (all P<0.05). SOFA had a relatively favorable prediction performance on NFS (AUC = 0.701, 95%CI: 0.596-0.802). After adjusting for related diseases, its prediction performance was increased. When SOFA was combined with lactate and gender, the model showed an AUC of 0.888 (95%CI: 0.759-1.000) and 0.3-0.9 prediction possibility. Further, the SOFA also showed significant relationship with hospital-LOS, ICU-LOS, and in-hospital mortality (all P<0.05), and exerted some value in the prediction of 7-day hospital-LOS (AUC = 0.637, 95%CI: 0.575-0.686) and in-hospital mortality (AUC = 0.637, 95%CI: 0.680-0.845).

CONCLUSIONS

SOFA score was related to the NFS and can be regarded as a useful indicator for predicting the NFS in patients with AAA.

Association Between Red Cell Distribution Width and Liver Injury after Cardiac and Aortic Aneurysm Surgery with Cardiopulmonary Bypass

OBJECTIVES

This study aimed to investigate the association between preoperative red blood cell distribution width (RDW) levels and liver injury (LI) after cardiac surgery, to highlight RDW's usefulness in the early identification and intervention for patients at high risk of LI.

DESIGN

A retrospective observational study.

SETTING

A university-affiliated teaching hospital and tertiary referral center.

PARTICIPANTS

Adult patients who underwent cardiac and aortic aneurysm surgery at Changhai Hospital in 2021.

INTERVENTIONS

Postoperative LI was defined by increased liver enzyme levels and/or hyperbilirubinemia, noted from the time of surgery to discharge. Logistic regression analyses were conducted to examine the RDW-LI relationship, with stratified analyses based on age, gender, and anemia. Survival within 30 days was assessed using the Kaplan-Meier method, with survival curve differences analyzed via the log-rank test. The study included 3 sets of sensitivity analyses.

MEASUREMENTS AND MAIN RESULTS

Postoperative LI was observed in 75 patients (10%). Multivariate regression analysis showed a significant association between high RDW levels and postoperative LI (adjusted odds ratio, 3.25; p = 0.033; 95% confidence intefal, 1.10-9.63), even after adjusting for all covariates. This association remained consistent across 3 sets of sensitivity analyses. Subgroup analysis showed men had a higher correlation with LI (p for interaction = 0.041). Kaplan-Meier analysis indicated a significantly lower survival rate in the LI group (76%) compared with the non-LI group (99.6%; p < 0.001).

CONCLUSIONS

Preoperative RDW levels are significantly associated with postoperative LI. RDW could serve as a significant useful marker for early detection and intervention in patients at high risk of LI, thereby potentially improving patient outcomes.

Relationship between Preoperative Red Cell Distribution Width and Prolonged Postoperative Use of Catecholamines in Minimally Invasive Mitral Valve Surgery Patients: A Retrospective Cohort Study

Background/Objectives: Elevated RDW has emerged in cardiac surgery as a potential means of preoperative risk stratification with the capacity to predict short- and long-term postoperative mortality, acute kidney injury, and postoperative atrial fibrillation. The question as to whether perioperative hemodynamic instability may be predicted by such a marker remains a topic of ongoing debate. The aim of this study was to explore the relationship between preoperative RDW and prolonged postoperative catecholamine use in minimally invasive mitral valve surgery. Methods: We performed a retrospective monocentric cohort study in an academic hospital; we enrolled patients who had undergone minimally invasive mitral valve surgery (including both robot-assisted and non-robot-assisted procedures) between January 2019 and December 2022. We considered the use of inotropes and/or vasopressors for at least twelve hours after post-surgery ICU admission to qualify as the prolonged postoperative use of catecholamines (PPUC). The RDW was obtained from the routine full blood count analysis performed upon admission or a maximum of 72 h before surgery. We also performed a multivariable logistic regression analysis with PPUC as the dependent variable. Results: We finally enrolled 343 patients. Upon multivariate analysis, RDW >14.4% was independently associated with prolonged postoperative catecholamine use when compared to the reference group (OR 2.62 [1.06-4.84]; p = 0.03). Moreover, the EuroSCORE II score (OR 1.38 [1.03-1.85]; p = 0.03), the cross-clamp time (OR 1.01 [1.01-1.02]; p < 0.01), and robot-assisted mitral valve surgery (OR 0.53 [0.30-0.93]; p < 0.03) were independently associated with the prolonged postoperative use of catecholamines. Conclusions: This study identified that an elevated preoperative RDW (>14.4%), the EuroSCORE II score, and the cross-clamp time independently predict prolonged postoperative catecholamine use in minimally invasive mitral valve surgery patients. Conversely, the robot-assisted approach was associated with a smaller hemodynamic impairment.

The red blood cell distribution width to albumin ratio was a potential prognostic biomarker for acute respiratory failure: a retrospective study

BACKGROUND

The association between red blood cell distribution width (RDW) to albumin ratio (RAR) and prognosis in patients with acute respiratory failure (ARF) admitted to the Intensive Care Unit (ICU) remains unclear. This retrospective cohort study aims to investigate this association.

METHODS

Clinical information of ARF patients was collected from the Medical Information Mart for Intensive Care IV (MIMIC-IV) version 2.0 database. The primary outcome was, in-hospital mortality and secondary outcomes included 28-day mortality, 60-day mortality, length of hospital stay, and length of ICU stay. Cox regression models and subgroup analyses were conducted to explore the relationship between RAR and mortality.

RESULTS

A total of 4547 patients with acute respiratory failure were enrolled, with 2277 in the low ratio group (RAR < 4.83) and 2270 in the high ratio group (RAR > = 4.83). Kaplan-Meier survival analysis demonstrated a significant difference in survival probability between the two groups. After adjusting for confounding factors, the Cox regression analysis showed that the high RAR ratio had a higher hazard ratio (HR) for in-hospital mortality (HR 1.22, 95% CI 1.07-1.40; P = 0.003), as well as for 28-day mortality and 60-day mortality. Propensity score-matched (PSM) analysis further supported the finding that high RAR was an independent risk factor for ARF.

CONCLUSION

This study reveals that RAR is an independent risk factor for poor clinical prognosis in patients with ARF admitted to the ICU. Higher RAR levels were associated with increased in-hospital, 28-day and 60-day mortality rates.

Predictive value of the early postoperative hemoglobin-to-red blood cell distribution width ratio for acute kidney injury in elderly intertrochanteric fracture patients

BACKGROUND

Hemoglobin-to-red blood cell distribution width ratio (HRR) had great predictive value for the prognosis of malignant tumors and cardiovascular disease. However, its predictive value for the occurrence of acute kidney injury (AKI) in elderly intertrochanteric fracture patients remains unclear. This study aims to analyze the correlation between the early postoperative HRR and the risk of postoperative AKI in elderly intertrochanteric fracture patients.

METHODS

We reviewed the medical records of 307 elderly intertrochanteric fracture patients in this single-center retrospective cohort study. We performed univariate analysis on the relevant parameters, and parameters with significant differences were included in the following logistic regression model for multivariate analysis. Then, we used a receiver operating characteristic (ROC) curve to evaluate the predictive value of the early postoperative HRR level for AKI in elderly intertrochanteric fracture patients. Patients were divided into a high HRR group and a low HRR group according to the cutoff point determined by ROC curve analysis. Subsequently, the relevance between postoperative HRR and AKI was further determined using propensity score matching (PSM) and inverse probability of treatment weighting (IPTW).

RESULTS

The area under the curve of the early postoperative HRR for predicting postoperative AKI was 0.714 (95% CI: 0.618-0.809). The cutoff value was 5.44. The sensitivity was 72.7%, and the specificity was 70.8%. Patients were divided into low HRR (⩽ 5.44) and high HRR (> 5.44) groups according to the cutoff value. PSM and IPTW analysis indicated that the risk of AKI in the low HRR group was significantly higher than that in the high HRR group in both the matched cohort (OR = 6.914, 95% CI: 1.714-46.603, p = 0.016) and the weighted group (OR = 2.784, 95% CI: 1.415-5.811, p = 0.040).

CONCLUSIONS

Early postoperative HRR is an accurate, accessible, and economical blood test parameter that can predict the risk of postoperative AKI in elderly patients with femoral intertrochanteric fracture.

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.

Effect of Long-Term Reduction of Deuterium Content in the Body on Hemoglobin Production and Parameters of Erythropoiesis

Anemia is the most widespread hematological disease, therefore the search for new approaches to erythropoiesis regulation in the body remains an extremely urgent problem. We studied the effect of long-term reduction of deuterium level in the internal milieu of the body on hemoglobin production and parameters of erythropoiesis in sexually mature male Wistar rats. The animals consumed water with deuterium content decreased to 10 ppm for 2 months. After 1 month, an increase of hemoglobin synthesis in erythrocytes was detected, and after 2 months we observed intensification of erythropoiesis. Since the observed processes occurred in healthy animals with initially normal indices of hematopoiesis, the obtained data allow us to consider the reduction of deuterium level in the internal milieu of the body as a factor of erythropoiesis regulation and a possible option of its alternative non-pharmacological regulators.

Association Between Red Blood Cell Distribution Width and Coronary Calcification in Patients Referred for Invasive Coronary Angiography

This study aimed to determine whether red cell distribution width (RDW) is associated with coronary calcification. A total of 4796 patients who underwent coronary computed tomography angiography and subsequent invasive coronary angiography were consecutively enrolled. Coronary artery calcium score (CACS), demographic, clinical, and laboratory data were collected from electronic medical records. RDW were expressed in two forms, as a coefficient of variation (CV) or as a standard deviation (SD). Multivariable ordinal logistic regression was used to investigate the association of RDW with CACS grades (CACS 0-99, 100-399, 400-999, and >1000). A significant association was found between elevated RDW-SD and higher CACS grades after full adjustment (adjusted OR per 1-SD increase: 1.11, 95% CI: 1.05-1.18; P < .001), while no significant association was found between RDW-CV and CACS grades. When RDW-SD was analyzed as a categorical variable, it was primarily the 4th quartile of RDW-SD that was associated with elevated CACS grades compared with the 1st quartile (adjusted OR: 1.25, 95% CI: 1.07-1.46; P = .006), while the 2nd and 3rd quartiles showed no significantly higher risk. RDW-SD is a more robust biomarker for coronary calcification compared with RDW-CV.