Prevalence and Outcomes of Anemia and Hematinic Deficiencies in Patients With Chronic Heart Failure

Abstract

IMPORTANCE: Detailed information on the prevalence, associations, and consequences of anemia and iron deficiency in epidemiologically representative outpatients with chronic heart failure (HF) is lacking. OBJECTIVE: To investigate the epidemiology of anemia and iron deficiency in a broad range of patients referred to a cardiology clinic with suspected HF. DESIGN, SETTING, AND PARTICIPANTS: We collected clinical data, including hemoglobin, serum iron, transferrin saturation, and serum ferritin concentrations, on consecutive patients referred with suspected HF to a single outpatient clinic serving a local community from January 1, 2001, through December 31, 2010. Follow-up data were censored on December 13, 2011. Patients underwent phenotyping by echocardiography and plasma N-terminal pro-brain natriuretic peptide measurement and were followed for up to 10 years. MAIN OUTCOME MEASURES: Prevalences of anemia and iron deficiency and their interrelationship, all-cause mortality, and cardiovascular mortality. RESULTS: Of 4456 patients enrolled in the study, the median (interquartile range) age was 73 (65-79) years, 2696 (60.5%) were men, and 1791 (40.2%) had left ventricular systolic dysfunction (LVSD). Of those without LVSD, plasma N-terminal pro-brain natriuretic peptide concentration was greater than 400 pg/mL in 1172 (26.3%), less than 400 pg/mL in 841 (18.9%), and not measured in 652 (14.6%). Overall, 1237 patients (27.8%) had anemia, with a higher prevalence (987 [33.3%]) in patients who met the criteria for HF with or without LVSD. Depending on the definition applied, iron deficiency was present in 270 (43.2%) to 425 (68.0%) of patients with and 260 (14.7%) to 624 (35.3%) of patients without anemia. Lower hemoglobin (hazard ratio 0.92; 95% CI, 0.89-0.95; P < .001) and serum iron (hazard ratio 0.98; 95% CI, 0.97-0.99; P = .007) concentrations were independently associated with higher all-cause and cardiovascular mortality in multivariable analyses. CONCLUSIONS AND RELEVANCE: Anemia is common in patients with HF and often associated with iron deficiency. Both anemia and iron deficiency are associated with an increase in all-cause and cardiovascular mortality and might both be therapeutic targets in this population.