A new study published in Kidney & Blood Pressure Research investigated the hypothesis that red blood cell distribution width (RDW) is an independent predictor of acute kidney injury (AKI) and mortality in patients in the coronary care unit (CCU). This prospective, observational study, screened 412 adults admitted to the CCU from January 1, 2014 to June 1, 2015. AKI was defined based on the KDIGO-AKI criteria. The survivors were followed up for up to two years after hospital discharge. The results revealed that RDW was significantly correlated with the acute physiology and chronic health evaluation II (APACHEII) score, hemoglobin, mean corpuscular volume, inflammatory marker levels, nutrition and renal function at the time of CCU admission. The incidence of AKI was much higher in the high RDW group than in the low RDW group; RDW was independently associated with the incidence of AKI. However, 61 patients died during their hospital stay, and baseline RDW was also an independent predictor of in-hospital mortality. Furthermore, patients with a high RDW exhibited significantly higher 2-year mortality than patients with a low RDW during a median follow-up period of 19.8 months, and RDW independently predicted the risk of 2-year mortality, after adjustments for other clinical and laboratory variables. Hence, it was inferred that RDW is an independent predictor of AKI and mortality for patients in the CCU.