Investigation of the relationship between red blood cell distribution width and mortality in patients with hemophagocytic lymphohistiocytosis: a retrospective study

BACKGROUND: Red blood cell distribution width (RDW) is related to sepsis-related mortality. Hemophagocytic lymphohistiocytosis (HLH) is a syndrome caused by severe infection, tumors, or autoimmunity without a specific diagnosis. OBJECTIVE: To explore the correlation between RDW and mortality in patients with HLH. DESIGN AND SETTING: A retrospective study conducted in a hospital in China. METHODS: A total of 101 inpatients with HLH from January 1, 2017 to December 31, 2021 were divided into non-survivor (n = 52) and survivor (n = 49) groups. A non-parametric test was used to analyze demographic, clinical, and laboratory data between groups. Independent variables with P < 0.05 were analyzed using binary logistic regression to screen out mortality-related variables. Selected variables were subjected to multivariate logistic regression analysis, and those with strong correlations were screened. Receiver operating characteristic (ROC) curves of strongly correlated variables and area under curve (AUC) values were obtained. RESULTS: The APACHE II score, RDW, and platelet (PLT) and fibrinogen (FIB) levels (P < 0.05) different significantly. RDW, PLT, FIB were correlated with mortality. The AUC values of RDW, PLT, and FIB were 0.857, 0.797, and 0.726, respectively. RDW was associated with mortality in patients with HLH (P < 0.01, cut-off value: 16.9). The sensitivity and specificity of predicting mortality were 97.96% and 96.1%, respectively. CONCLUSION: Logistic regression analysis showed a correlation between RDW and patients’ mortality. Therefore, RDW can be used to predict mortality in patients with HLH.