Aim: In several diseases, a relationship has been shown between mortality and a high level of red blood cell distribution width (RDW). The aim of this study was to investigate the relationship between mortality and RDW measured in patients in the Intensive Care Unit (ICU), and to compare the RDW values with the Acute Physiology and Chronic Health Evaluation (APACHE-II) score, which is accepted as an independent risk factor for mortality. Material and Method: A retrospective evaluation was made of the demographic data, disease diagnoses, laboratory data and APACHE-II scores of ICU patients between January 2013 and December 2014. Results: A total of 233 patients were included in the study. The mean age was 74 years (range, 19- 96 years) and the mortality rate was 25.32%. The RDW value and APACHE-II score at the time of admission to ICU were determined to be higher in the patients with mortality than in those who survived (p<0.001). In the multivariable logistic regression analysis, a ROC curve was drawn for each patient to determine the diagnostic accuracy of the RDW (p<0.05, OR=0.870) and APACHE II (p<0.001, OR=0.723) values determined as independent markers of mortality status, and mortality predictive capability was examined. In the prediction of mortality, sensitivity was 66.1% and specificity was 66.1% for RDW (AUC = 0.689, optimal cutoff value = 14.5), and for APACHE II scores, sensitivity was calculated as 86.4% and specificity as 81% (AUC = 0.902, optimal cutoff value = 17.5). Conclusion: The results of this study determined a relationship between increased RDW values and mortality in ICU patients. Although the rates of predicting mortality were not as high as those of the APACHE II score, RDW alone, which is a low-cost and readily available test, can be considered an extremely valuable parameter for the prediction of mortality rates.
