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.
