Background. The relationship between anaemia and congestion in HF and its prognostic role are controversial. The aim of this study was to evaluate the relationship between anaemia and biomarkers of central/peripheral congestion in HF and the impact on mortality.
Methods. We retrospectively evaluated 434 acute/chronic HF (AHF/CHF) patients. Anaemia was defined as haemoglobin (Hb) levels < 12 g/dL in women and < 13 g/dL in men. We evaluated brain natriuretic peptide (BNP, central congestion biomarker) and Hydration Index (HI %, bioimpedance vector analysis, peripheral congestion biomarker). The endpoint was all-cause mortality.
Results. Anaemia occurred in 59% of patients with AHF and in 35% with CHF (p<0.001) and showed significant correlation with NYHA functional class and renal function. BNP and HI were significantly higher in patients with than in those without anaemia. Independent predictors of anaemia included BNP, estimated creatinine clearance (eCrCL), and HI. During a median follow-up of 463 days, all-cause mortality rate was 21% which was significantly higher in patients with than in those without anaemia (30% vs 14%, p<0.001; HR 2.6). At multivariate Cox regression analysis BNP, eCrCL, and HI confirmed as independent predictors for mortality (HR 1.0002, HR 0.97, and HR 1.05, respectively), while anaemia did not confirm its predictive value.
Conclusions. Anaemia correlates HF status, functional class, renal function and biomarkers of central/peripheral congestion. Indeed, anaemia was not an independent predictor for mortality. Therefore, anaemia in HF seems rather a marker of disease severity in patients with high congestion burden than a predictor of death.