Prognostic value of red blood cell distribution width for severe acute pancreatitis

BACKGROUND: Severe acute pancreatitis (SAP) is a common condition in the intensive care unit (ICU) and has a high mortality. Early evaluation of the severity and prognosis is very important for SAP therapy. Recently, red blood cell distribution (RDW) was associated with mortality of sepsis patients and could be used as a predictor of prognosis. Similarly, RDW may be associated with the prognosis of SAP patients and be used as a prognostic indicator for SAP patients. AIM: To investigate the prognostic value of RDW for SAP patients. METHODS: We retrospectively enrolled SAP patients admitted to the ICU of the First Affiliated Hospital of China Medical University from June 2015 to June 2017. According to the prognosis at 90 d, SAP patients were divided into a survival group and a non-survival group. RDW was extracted from a routine blood test. Demographic parameters and RDW were recorded and compared between the two groups. The receiver operator characteristic (ROC) curve was constructed and Cox regression analysis was performed to investigate the prognostic value of RDW for SAP patients. RESULTS: In this retrospective cohort study, 42 SAP patients were enrolled, of whom 22 survived (survival group) and 20 died (non-survival group). The baseline parameters were comparable between the two groups. The coefficient of variation of RDW (RDW-CV), standard deviation of RDW (RDW-SD), Acute Physiology and Chronic Health Evaluation II (APACHE II) score, and Sequential Organ Failure Assessment (SOFA) score were significantly higher in the non-survival group than in the survival group (P < 0.05). The RDW-CV and RDW-SD were significantly correlated with the APACHE II score and SOFA score, respectively. The areas under the ROC curves (AUCs) of RDW-CV and RDW-SD were all greater than those of the APACHE II score and SOFA score, among which, the AUC of RDW-SD was the greatest. The results demonstrated that RDW had better prognostic value for predicting the mortality of SAP patients. When the RDW-SD was greater than 45.5, the sensitivity for predicting prognosis was 77.8% and the specificity was 70.8%. Both RDW-CV and RDW-SD could be used as independent risk factors to predict the mortality of SAP patients in multivariate logistic regression analysis and univariate Cox proportional hazards regression analysis, similar to the APACHE II and SOFA scores. CONCLUSION: The RDW is greater in the non-surviving SAP patients than in the surviving patients. RDW is significantly correlated with the APACHE II and SOFA scores. RDW has better prognostic value for SAP patients than the APACHE II and SOFA scores and could easily be used by clinicians for the treatment of SAP patients.