Elevated red blood cell distribution width at ICU discharge is associated with readmission to the intensive care unit

Association of mean RDW values and changes in RDW with in-hospital mortality in ventilator-associated pneumonia (VAP): Evidence from MIMIC-IV database

INTRODUCTION

Ventilator-associated pneumonia (VAP) is a hospital-acquired infection with high mortality, and remains a challenge for clinical treatment. Red blood cell distribution width (RDW) was associated with worse outcomes in several diseases. The purpose of this study was to investigate the relationship between mean RDW values, changes in RDW (delta RDW), and in-hospital mortality among patients with VAP.

METHODS

In the present study, we enrolled 1266 VAP patients from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. All patients were categorized into low group, medium group, and high group according to tertiles of mean RDW values. The primary outcome was all-cause in-hospital mortality. Univariate logistic regression analysis, multivariate logistic regression analysis, and restricted cubic spline (RCS) curve were performed to determine the association between mean RDW values and in-hospital mortality in VAP. Moreover, RCS curve was plotted to explore the dose-response relationship between delta RDW and in-hospital mortality in VAP.

RESULTS

Among the VAP patients included in the study, the in-hospital mortality was 20.85% with 264 non-survivors and 1002 survivors. The non-survivors exhibited significantly higher mean RDW values and delta RDW values compared to survivors. Multivariate logistic regression analysis indicated that mean RDW values were positively associated with in-hospital mortality in VAP after adjusting for relevant covariates. The RCS curve demonstrated a dose-response relationship between mean RDW and the mortality in VAP. Moreover, a linear relationship was observed between delta RDW and in-hospital mortality in VAP.

CONCLUSION

Higher mean RDW values were significantly associated with an increased risk of in-hospital mortality in VAP. Additionally, a linear relationship was found between delta RDW values and in-hospital mortality. These findings suggest that RDW can be used to identify high-risk patients with poorer outcomes in VAP.

Biological age as a predictor of unplanned intensive care readmission during the same hospitalization

BACKGROUND

Biological age is increasingly being recognized as an important predictor of health but its utility in acute care setting remains uncertain.

OBJECTIVE

We assessed whether biological age on intensive care unit (ICU) admission can predict unplanned ICU readmission during the same hospitalization.

METHODS

The Levine PhenoAge model based on biomarkers of DNA methylation was used to determine each patient's biological age. The difference between PhenoAge and chronological age was indexed to the local context by regressing PhenoAge on chronological age using linear regression. A positive residual implied one's biological age was older than the corresponding chronological age compared to other patients - defined as PhenoAgeAccel.

RESULTS

Of the 2950 patients included, 153 (5.2%) had unplanned ICU readmission. Chronological age, Acute Physiology and Chronic Health Evaluation II score, the use of mechanical ventilation, vasopressor, or renal replacement therapy were not significantly different between those with and without readmission. PhenoAgeAccel was, however, more common among those who had unplanned ICU readmission (52% vs 43%, p =0.031). Quantitatively, the degree of phenotypical age above chronological age exhibited a 'dose-related' relationship with the risk of readmission (odds ratio 1.12, 95% confidence interval 1.01-1.24; p=0.040) after adjusting for chronological age, comorbidities, and severity of acute illness in the index (first) ICU admission.

CONCLUSION

Biological age was predictive of unplanned ICU readmission during the same hospitalization.

Impact of Red Cell and Platelet Distribution Width in Patients of Medical Intensive Care Unit

Introduction The red blood cell distribution width (RDW) is a measurement of variations in the size of red blood cells. As the width increases, the rate of mortality also increases, although the reason for it is still not known. On the other hand, platelet distribution width (PDW) is also useful in predicting morbidity and mortality in sepsis and other critically ill patients. In our study, we planned to study the impact of both RDW and PDW and evaluate their prognostic importance with outcome in patients admitted in medicine intensive care unit (MICU). Material and Method In these cross-sectional observational studies, 1,300 patients were included who were admitted in MICU. Critically ill patients were defined on the basis of qSOFA score greater than 2. PDW and RDW were obtained from Coulter report of complete blood count. Parameters included in Acute Physiology and Chronic Health Evaluation (APACHE) IV scores were taken and APACHE IV score was calculated. Correlation of RDW and PDW with outcomes such as length of ICU stay, use of mechanical ventilator, and discharge/death was done. Result The mean RDW (%) for the entire study population was 15.17 ± 3.01. The RDW (%) was significantly on the higher side in patients who succumbed to the disease as compared with the patients who were discharged. The correlation between the length of ICU stay (days) and RDW (%) was moderately positive and was significant (rho = 0.37, p ≤ 0.001). The correlation between the length of ICU stay (days) and PDW (%) was moderately positive and was significant (rho = 0.5, p ≤ 0.001). Conclusion RDW and PDW were found as significant indicators for period of stay in ICU, requirement for mechanical ventilation, and mortality rate in patients admitted to ICUs. As these are simple, easy to conduct, universally available tests, they can be regularly incorporated in patients admitted in ICUs.

Nursing workload on the day of discharge from the intensive care unit is associated with readmission

PURPOSE

To verify whether there is an association between the Nursing Activities Score (NAS) on the day of discharge from the intensive care unit and readmission..

MATERIALS AND METHODS

A retrospective cohort study of all patients admitted to the intensive care unit of Hospital Ernesto Dornelles, Porto Alegre, Brazil, who were discharged to the ward from October 2018 to December 2019. We collected demographic and clinical variables of the patients and the Nursing Activities Scoreon the day of discharge. Patients were followed up until the day of hospital discharge or death.

RESULTS

We included 1045 patients in the final sample. One hundred eighty-eight (18.0%) patients were readmitted, in addition there were two (0.2%) unexpected deaths that occurred in the ward. The median NAS was 59.9 (50.9-67.3), which was higher in the bivariate analysis in patients who were readmitted (64.0, 55.7-71.4) than in patients who were not readmitted (58.7, 49.7-66.1) (p < 0.001). Patients with a Nursing Activities Score  ≥ 60.0 and < 60.0 had rates of readmission of 23.4% and 12.7%, respectively (p < 0.001). After multivariable adjustment, the Nursing Activities Score at discharge maintained an association with readmission. In addition, in the Cox regression, the Nursing Activities Score as a dichotomous variable was independently associated with readmission (adjusted HR 1.560; CI 1.146-2.125; p = 0.005).

CONCLUSIONS

We found that the nursing workload, assessed by the Nursing Activities Score at the time of discharge from the intensive care unit, was associated with risk of readmission..

A Novel Switching State-Space Model for Post-ICU Mortality Prediction and Survival Analysis

Predicting mortality risk in patients accurately during and after intensive care unit (ICU) stay is an essential component for supporting critical care decision-making. To date, various scoring systems have been designed for survival analysis and mortality prediction by providing risk scores based on patient's vital signs and lab results. However, it is challenging using these universal scores to represent the overall severity level of illness and to look into patient's deterioration leading to high mortality risk during ICU stay. Thus, a close monitoring of the severity level over time during ICU stay is more preferable. In this study, we design a new switching state-space model by correlating patient's condition dynamics in last hours of ICU stay to the risk probabilities in a short time period (1-6 days) after ICU discharge. More specifically, we propose to integrate a cumulative hazard function estimating survival probability into the autoregressive hidden Markov model using time-interval sequential SAPS II scores as features. We demonstrate the significant improvement of mortality prediction comparing to SAPS I, SAPS II, and SOFA scoring systems for the PhysioNet MIMIC II Challenge data.

Red Blood Cell Distribution Width, Neutrophil-to-Lymphocyte Ratio, and In-Hospital Mortality in Dyspneic Patients Admitted to the Emergency Department

Red blood cell distribution width (RDW) and neutrophil-to-lymphocyte ratio (NLR) have shown a prognostic value in various clinical settings. We aimed to investigate the association between RDW, NLR, and in-hospital mortality in patients with dyspnea. In this retrospective study with the Medical Information Mart for Intensive Care III database (version 1.4), adult patients who came to the emergency department with dyspnea were included. Patients' comorbidities, hematological parameters within the first 48 hours after admission to the emergency department, and in-hospital mortality were extracted. The relationships between RDW, NLR, and in-hospital mortality were analyzed with the receiver operating characteristic (ROC) curve analysis and multivariate logistic regression model. We found that hospital survivors had significantly lower NLR than those who died. However, RDW was not significantly increased in patients who died during the hospitalization. The area under the ROC curve of NLR for predicting in-hospital mortality was 0.62. On multivariate analysis, NLR was not independently associated with in-hospital mortality. On further analysis, lymphocyte percentage was independently associated with in-hospital mortality, with an odds ratio of 0.56. Therefore, we concluded that RDW and NLR are not reliable parameters to predict in-hospital mortality in critically ill patients admitted to the emergency department with dyspnea.

The Relationship Between Hematological Parameters and Mortality in Cardiovascular Patients With Postcardiac Arrest Syndrome

Background: Post-cardiac arrest syndrome is the insufficiency of cardiac and cerebral functions caused by ischemia after sudden cardiac arrest. We aimed to determine the hematological parameters associated with mortality in the intensive care follow-up of patients with post-cardiac arrest syndrome.

Methods: The hematological parameters of 285 cardiovascular patients who were admitted to the emergency department of Harran University Medical Faculty between 2013 and 2018 and followed up in the intensive care unit with post-cardiac arrest syndrome were examined. A total of 85 patients were included in the study. These parameters were recorded as the time of arrival to the emergency department (0 hour) and hematological parameters at the 24^th and 48^th hours of intensive care follow-up.

Results: In the mortality group, albumin (P:0.030), hemoglobin (Hg) (P: 0.049), and hematocrit (HCT) (P: 0.020) values ​​in the blood parameters, at the time of admission to the emergency department, were significantly lower than those in the survival group. Red blood cell distribution width (RDW) (P: 0.009) and urea (P <0.001) values ​​at the time of arrival were higher than the survival group. In the 24^th and 48^th hours, mean hemoglobin (MCHC) (P <0.05) values ​​were lower and RDW (P <0.05) values ​​were higher in the mortality group compared to the survival group.

Conclusions: In this retrospective validation, low albumin, Hg, HCT, MCHC, and high RDW and urea levels may increase mortality in cardiovascular patients who develop post-cardiac arrest syndrome within the first 48 hours. Correcting these values ​​early may reduce mortality.

Association between anemia and hematological indices with mortality among cardiac intensive care unit patients

Background

Anemia and elevated red cell distribution width (RDW) or mean corpuscular volume (MCV) are associated with an adverse prognosis in patients with cardiovascular disease and critical illness. Limited data exist regarding these associations in unselected cardiac intensive care unit (CICU) patients.

Methods

Retrospective cohort study of CICU patients between January 1, 2007, and December 31, 2015, with a hemoglobin (Hb) level measured at admission. Multivariable regression was performed to determine predictors of hospital mortality, and Kaplan–Meier analysis was used to determine post-discharge survival.

Results

We included 9644 patients with a mean age of 67.5 ± 15.1 years, including 3604 (37.4%) females. The median (IQR) values of Hb, MCV and RDW were 12.2 g/dL (10.6, 13.7), 90.7 fL (87.3, 94.2) fL, and 14.1% (13.3, 15.8), respectively. Anemia (admission Hb < 12 g/dL) was present in 4434 (46%) patients. A total of 845 (8.8%) patients died in the hospital. Patients with anemia had higher hospital mortality (11.3% vs. 6.6%, unadjusted OR 1.82, 95% CI 1.58–2.10, p < 0.001). After multivariable regression, admission Hb and MCV were not significantly associated with hospital mortality (both p > 0.1), while admission RDW (adjusted OR 1.12 per 1%, 95% CI 1.07–1.18, p < 0.001) was significantly associated with hospital mortality. Hospital survivors with lower Hb, higher MCV, or higher RDW had lower post-discharge survival.

Conclusion

Elevated RDW on admission was independently associated with higher hospital mortality in CICU patients. These data emphasize the importance of hematologic abnormalities for mortality risk stratification in CICU populations.

Graphic abstract

Electronic supplementary material

The online version of this article (10.1007/s00392-019-01549-0) contains supplementary material, which is available to authorized users.

Red blood cell distribution width provides additional prognostic value beyond severity scores in adult critical illness

BACKGROUND

The prognostic value of red blood cell distribution width (RDW) in critical illness remains controversial. The aim of this study was to investigate the prognostic value of on-admission RDW for in-hospital and 4-year mortality in adults with critical illness.

METHODS

This is a retrospective cohort study from the Medical Information Mart for Intensive Care III (MIMIC III) database (version 1.4). Patients admitted to the intensive care unit (ICU) for the first time were included. Their on-admission RDW and severity scores were extracted with the Structured Query Language (SQL). The patients were categorized into a training set and a validation set. The relation of RDW to in-hospital and 4-year all-cause mortality was analyzed using receiver operating characteristic (ROC) curve, Kaplan-Meier curve, Cox model, net reclassification index (NRI), integrated discriminatory index (IDI) and nomogram.

RESULTS

A total of 36,532 patients (21,090 in training and 15,442 in validation set) were included in this study. Increased RDW was significantly associated with higher in-hospital and 4-year mortality. The prognostic value of RDW for 4-year mortality was independent of conventional severity scores. Using conventional severity scores as covariates the continuous NRI and IDI of RDW for in-hospital mortality were around 0.3-0.5 and 0.01-0.03, respectively. For 4-year mortality the NRI was around 0.2-0.3 and IDIs was around 0.03-0.08.

CONCLUSIONS

Admission RDW predicts both in-hospital and 4-year mortality in adult patients with critical illness admitted in the ICU, and can provide additional prognostic values beyond conventional clinical severity scores.

Red Blood Cell Distribution Width Predicts 1-month Complications after Percutaneous Transluminal Angioplasty

Background

The identification of patients at higher risk of developing percutaneous transluminal angioplasty (PTA)-related complications is pivotal for achieving better clinical outcomes. We carried out a single-center, observational, retrospective study to explore whether in-hospital changes of red blood cell distribution width (RDW) may help predicting early development of PTA-related complications.

Methods

The study population consisted of all consecutive patients who underwent PTA for severe peripheral artery occlusive disease (PAOD) during a 2-year period. RDW was measured at hospital admission and discharge, and the delta was calculated. Patient follow-up was routinely performed 1-month after hospital discharge, and was based on thoughtful medical assessment and arterial ultrasonography. The control population consisted of 352 ostensibly healthy subjects.

Results

The final PTA group consisted of 224 patients. Hemoglobin was lower, whilst mean corpuscular volume (MCV) and RDW were higher in PAOD cases than in controls. Overall, 11 PAOD patients (4.9%) developed clinically significant PTA-related complications 1-month after hospital discharge. Patients who developed 1-month PTA-related complications had lower hemoglobin concentration, but higher RDW and delta RDW than those who did not. Patients with delta RDW >1 had 60% higher risk of developing 1-month PTA-related complications and 88% higher risk of developing early reocclusion. Overall, RDW exhibited an area under the curve (AUC) of 0.68 and 0.74 for predicting 1-month PTA-related complications and early reocclusion, respectively.

Conclusions

The results of this study suggest that RDW may play a role for guiding the clinical decision making of PTA patients immediately after hospital discharge.

Is red blood cell distribution width a marker of severity in patients discharged from the ICU?

We have read the study about the association between high red blood cell distribution width and higher ward mortality after intensive care unit discharge. The study increases the evidence that RDW may be a marker of severity for patients discharged from the ICU. However, in this letter, we comment on issues that need further discussion.