Objectives: Our aim was to examine the relationships between serum hematocrit (Hct) and risk of all-cause mortality among patients with severe heart failure (HF).
Background: Anemia occurs with increased frequency in severe HF. However, few studies have examined the impact of anemia on mortality in this population.
Methods: Using a prospective cohort design, we evaluated the relationships between baseline serum Hct and mortality among 1,130 patients with left ventricular EF <30% and New York Heart Association functional class IIIB or IV HF treated with angiotensin-converting enzyme inhibitors, diuretics, and digitalis. Mortality was ascertained by centralized adjudication.
Results: The mean Hct was 41.8% (range 25.4% to 58.8%). Over 15 months of mean follow-up, there were 407 deaths (29 per 100 person-years). After adjustment for potential confounders, those in the lowest quintile of Hct (range 25.4% to 37.5%) had a 52% higher risk of death (hazard ratio 1.52, 95% confidence interval 1.11 to 2.10), compared with the highest quintile (range 46.1% to 58.8%). Within the lowest quintile of Hct, each 1% decrease in Hct was associated with an 11% higher risk of death (p < 0.01), whereas within the four higher quintiles of Hct, Hct was not associated with total mortality. Evaluation of different causes of death indicated that a lower Hct was strongly associated with death from progressive HF, rather than sudden death or other deaths.
Conclusions: Among patients with severe HF, anemia is a significant independent risk factor for death, with a progressively higher risk with increasing severity of anemia. Further investigation of the etiologies, prevention, and treatment of anemia in severe HF is warranted.