Baseline anemia is not a predictor of all-cause mortality in outpatients with advanced heart failure or severe renal dysfunction. Results from the Norwegian Heart Failure Registry

Abstract

Objectives: The aim of this study was to evaluate the prognostic impact of anemia in outpatients with chronic heart failure attending specialized heart failure clinics and specifically to investigate its prognostic utility in patients with severe renal dysfunction or advanced heart failure.

Background: Anemia is an independent prognostic marker in patients with heart failure. The effect of anemia on mortality decreases with increasing creatinine levels.

Methods: Multivariate Cox regression analyses were used to investigate the prognostic effect of anemia in 4,144 patients with heart failure from 21 outpatient heart failure clinics in Norway. Severe renal failure was defined as estimated glomerular filtration rate ≤45 ml/min/1.73 m(2) and advanced heart failure as New York Heart Association functional classes IIIb and IV.

Results: Baseline anemia was present in 24% and was a strong predictor of all-cause mortality (adjusted hazard ratio [HR]: 1.30, 95% CI: 1.09 to 1.56, p = 0.004). Baseline anemia did not predict mortality in the 752 patients with severe renal dysfunction (adjusted HR: 1.08, 95 % CI: 0.77 to 1.51, p = 0.662) and the 528 patients with advanced heart failure (adjusted HR: 0.87, 95% CI: 0.56 to 1.34, p = 0.542). In the 1,743 patients who attended subsequent visits, sustained anemia independently predicted worse prognosis (adjusted HR: 1.47, 95% CI: 1.10 to 1.94, p = 0.008), whereas transient and new-onset anemia did not.

Conclusions: According to our study, baseline anemia was not an independent predictor of all-cause mortality in outpatients with heart failure and accompanied severe renal dysfunction or advanced heart disease. Sustained anemia after optimizing heart failure treatment might imply worse prognosis independently of renal function and New York Heart Association functional class.