The correlation between the hemoglobin-to-red cell distribution width ratio and all-cause mortality in patients with malignant tumors and sepsis: A retrospective cohort study using the MIMIC-IV database

Abstract

ObjectiveThe aim of the study was to investigate the correlation between the hemoglobin-to-red cell distribution width ratio (HRR) and all-cause mortality in patients with malignant tumors and sepsis.MethodsAll patients who met the inclusion criteria of the Medical Information Mart for Intensive Care(MIMIC)-IV were selected and divided into four groups according to the quartile range of HRR distribution. Kaplan-Meier (K-M) analysis was used to plot the 28-day survival curve, and the log-rank test was used to compare the prognosis in each HRR group. A Cox proportional hazards regression model was used to evaluate the prognosis of HRR as both a continuous and categorical variable, and a restricted cubic spline was used to study the effect of HRR, as a continuous variable, on the mortality in patients with malignant tumors and sepsis. Interaction and subgroup analyses were performed to evaluate the consistency of correlations.ResultsA total of 3926 patients were included in the study, including 934 patients in the HRR ≤ 4.97 group, 988 patients in the 4.97 < HRR ≤ 6.26 group, 1005 patients in the 6.26 < HRR ≤ 7.84 group, and 999 patients in the HRR ≥ 7.84 group. According to the K-M analysis, the 28-day survival rate was the lowest in the HRR ≤ 4.97 group (59.53%), and there were significant differences in survival rates among different HRR levels (P < 0.001). The Cox proportional hazards regression model found that after adjusting for various potential confounding factors, HRR was negatively correlated with 28-day and 365-day mortality, and the risk of death in the HRR ≥ 7.84 group was significantly lower than that in the HRR ≤ 4.97 group(P = 0.030 and P = 0.008, respectively). The restricted cubic spline plot revealed a linear and negative relationship between the HRR and the 28-day and 365-day mortality rates. Subgroup analysis revealed an interaction between HRR, blood urea nitrogen, and SAPS II scores (P = 0.010 and P = 0.048, respectively).ConclusionLow HRR is an independent risk factor for all-cause mortality in patients with malignant tumors and sepsis and could be used as a prognostic indicator for these patients.