Association Between Red Cell Distribution Width and Hospital Mortality in Patients with Sepsis

Abstract

Objective: Sepsis is the leading cause of death in patients admitted to adult intensive care units (ICUs). We aimed to determine the predictive value of red blood cell distribution width (RDW) in patients with sepsis in a large cohort.

Methods: This retrospective observational study used data from the eICU Collaborative Research Database. The prognostic value of RDW was investigated using the receiver operating characteristic (ROC) curve, multiple logistic regression model, integrated discriminatory index (IDI), and net reclassification index (NRI).

Results: In total, 9743 patients were included. The area under the ROC curve of the RDW for predicting hospital mortality was 0.631 (95% confidence interval [CI]: 0.616-0.645). Based on the multiple logistic regression model, an RDW of ≥14.5% was correlated with hospital mortality, regardless of Sequential Organ Failure Assessment (SOFA) and Acute Physiology and Chronic Health Evaluation IV (APACHE IV) scores (odds ratio [OR]: 1.838, 95% CI: 1.598-2.119). Using SOFA and APACHE IV scores as reference, the IDI and continuous NRI of RDW for hospital mortality was about 0.3 and 0.014, respectively.

Conclusions: The RDW may be useful in predicting hospital mortality in patients with sepsis, offering extra prognostic value beyond SOFA and APACHE IV scores.

Keywords: Acute Physiology and Chronic Health Evaluation IV; Red cell distribution width; Sequential Organ Failure Assessment; eICU Collaborative Research Database; hospital mortality; intensive care unit; sepsis.

Figure 1.

Patient selection process. * Key information refers to sex, Acute Physiology and Chronic Health Evaluation IV (APACHE IV) scores, mortality, and red blood cell distribution assessed within the first 24 hours after admission to the intensive care unit (ICU). SOFA, Sequential Organ Failure Assessment.

Figure 2.

Receiver operating characteristic curves of red blood cell distribution (RDW) and classical severity scores for hospital mortality. SOFA, Sequential Organ Failure Assessment; APACHE IV, Acute Physiology and Chronic Health Evaluation IV.

Figure 3.

Red blood cell distribution width (RDW) across all subgroups, classified by source of sepsis.

Figure 4.

Sensitivity analyses of complete case analysis and various random seeds in multiple imputations The red dot indicates the OR of the complete case analysis. Blue dots represent the OR of different multiple imputation seeds. Vertical lines indicate the 95% CI. The horizontal dotted line represents the position of OR = 1. OR, odds ratio; CI, confidence interval.