Association between red blood cell distribution width and all-cause mortality of patients after intra-aortic balloon pump in the intensive care unit

Heliyon. 2024 Mar 10;10(6):e27498. doi: 10.1016/j.heliyon.2024.e27498. eCollection 2024 Mar 30.

Abstract

Objectives: This study aimed to explore the relationship between red blood cell distribution width (RDW) and all-cause mortality in critically ill patients undergoing intra-aortic balloon pumping (IABP) in the intensive care unit (ICU).

Methods: This study retrospectively analyzed data from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. The primary endpoint was the 30-day mortality rate, while the secondary endpoint was the in-hospital mortality rate. Restricted cubic splines were used to assess the dose-response relationship. The receiver operating characteristic (ROC) curve and Kaplan-Meier curve analysis were carried out to evaluate the predictive performance of RDW. Moreover, multiple logistic regression analyses and subgroup analyses were conducted to investigate the relationship between RDW and 30-day mortality. Finally, propensity score matching (PSM) was performed to adjust for the imbalance of covariates.

Results: In total, 732 patients were finally identified from the MIMIC-IV database in this study. The RDW of patients in the non-survivor group was significantly higher compared with those in the survivor group (P < 0.01). Multiple logistic regression analyses corroborated RDW was an independent predictor of all-cause 30-day mortality in critically ill patients post-IABP. Meanwhile, ROC analysis identified an RDW cutoff of 14.2%. High RDW patients exhibited a 131% (OR = 2.31, 95% CI: 1.49-3.61) elevated risk of 30-day mortality after adjusting for confounders in multivariable logistic regression. After PSM, 412 patients were included in the matched cohort. In the original and matched cohorts, the high RDW group had higher 30-day and in-hospital mortality rates, as well as longer ICU stays. Lastly, the area under the ROC curve for 30-day mortality was 0.686, with an optimal cutoff point of 14.2 for RDW (sensitivity: 69.09 % and specificity: 63.32%).

Conclusion: RDW could be a simple and valuable prognostic tool to predict mortality in critically ill patients after IABP.

Keywords: Intra-aortic balloon pump; Mortality; Prognosis; Red blood cell distribution width.