Association of anemia and renal dysfunction with in-hospital mortality among patients hospitalized for acute heart failure syndromes with preserved or reduced ejection fraction

Background: The aim of this study was to evaluate the association of anemia and renal dysfunction with in-hospital outcomes in acute heart failure syndromes patients with preserved or reduced ejection fraction. Methods and results: Of the 4842 patients enrolled in the Acute Decompensated Heart Failure Syndromes (ATTEND) registry, 4693 patients were evaluated to investigate the association among anemia, renal dysfunction, a preserved or reduced ejection fraction and in-hospital mortality. They were divided into four groups based on hemoglobin and estimated glomerular filtration rate at admission. The in-hospital mortality rate was 5.9% and 6.9% of the preserved and reduced ejection fraction groups, respectively. After adjustment for multiple comorbidities, there was no association of either anemia or renal dysfunction alone with in-hospital mortality in preserved ejection fraction patients, but the combination of anemia and renal dysfunction was associated with a somewhat higher risk of in-hospital mortality than that without either condition (odds ratio (OR), 2.75; 95% confidence interval (CI), 0.72–10.41; p=0.137). In reduced ejection fraction patients, adjusted analysis showed that a significantly higher risk of in-hospital mortality was associated with anemia alone (OR, 2.56; 95% CI, 1.10-5.94; p=0.029) and with anemia plus renal dysfunction (OR, 2.34; 95% CI, 1.09–5.03; p=0.029) relative to the risk without either condition. Conclusions: Our findings demonstrate that anemia combined with renal dysfunction is not a risk factor for in-hospital mortality in patients with a preserved ejection fraction, whereas anemia is an independent predictor of in-hospital mortality risk in reduced ejection fraction patients regardless of renal dysfunction.