Association of anemia with outcomes of acute heart failure

Objectives: Anemia is common in patients presenting with acute congestive heart failure (CHF); when hemoglobin (HGB) declines to low levels, it can result in worse outcomes. The aim of this study was to determine a level of HGB on admission or discharge that affects outcomes in patients with CHF and then to evaluate the effect of the low HGB levels on these outcomes. Methods: We conducted a retrospective cohort study of 756 patients admitted with acute CHF during the period January 1, 2011-December 31, 2014. We used multivariable regression analysis to evaluate the relation among HGB levels and three major outcomes: 3-year mortality, 30-day readmission rate, and length of stay (LOS). Results: Compared with patients with HGB ≥10 g/dL, patients with HGB <10 g/dL on discharge from the hospital had higher mortality (3-year survival 46% vs 33%, P = 0.023) and 30-day readmission rates (23% vs 14%; P = 0.008) and increased LOS (4.8 vs 3.2 days, P < 0.001). Patients with admission HGB <10 g/dL had higher mortality rates (3-year survival 45% vs 32%, P = 0.019) and increased LOS (4.5 vs 3.4 days, P = 0.014). A lower admission HGB value was associated with higher 30-day readmission rates, but it was not statistically significant (P = 0.06). Conclusions: An HGB level <10 g/dL on admission or discharge in patients hospitalized with acute CHF is associated with a significantly worse outcome.