Objective The ratio of hemoglobin to red blood cell distribution width (Hb/RDW) is a simple and readily available tool associated with adverse outcomes in chronic heart failure (HF). However, the association between the Hb/RDW ratio and mortality in patients with acute decompensated HF (ADHF) is unclear. The goal of this study was to investigate the relationship between the Hb/RDW ratio and mortality in patients after ADHF. Methods This single-center study included clinical and laboratory data collected at baseline, with patients prospectively followed-up for a median period of 3.1 years. The patients were divided into two groups based on their median Hb/RDW ratio. Patients We evaluated 250 consecutive patients hospitalized for ADHF at Shinshu University Hospital between July 2014 and March 2019. Results In our study cohort [median age, 76 (66-83) years
62.8% male], all-cause death was observed in 91 patients (incidence rate: 12.7 per 100 patient-years). A Kaplan-Meier analysis revealed that patients in the lower Hb/RDW ratio group (<
0.24, n=131) had worse outcomes compared to those in the higher group (≥0.24, n=119) (cumulative incidence 44.1% vs. 19.5%, respectively
log-rank, p<
0.001). After adjusting for demographics, HF severity, and laboratory biomarkers, a lower Hb/RDW ratio was significantly associated with a higher risk of mortality (hazard ratio, 1.89
95% confidence interval, 1.04-3.45
p=0.038). Conclusion A lower Hb/RDW ratio is associated with an increased risk of mortality in patients after ADHF, thus indicating its potential utility in identifying patients at an elevated risk for future cardiovascular events.