Abstract P013: Prevalence and Outcomes of Anemia in Patients Hospitalized with Acute Decompensated Heart Failure: The ARIC Study Community Surveillance
Background: Anemia has been associated with increased mortality in heart failure patients. The prevalence and outcomes of anemia in patients hospitalized with acute decompensated heart failure (ADHF) in population-based settings are unknown.
Methods: Hospitalizations related to heart failure among black and white residents 55 years and older were sampled by stratified design from 4 US communities (total population age 55+ =177,000), January 1, 2005 -December 31,2008 in the Atherosclerosis Risk in Communities (ARIC) Study. Events were validated by physician review of medical records, and linked to mortality files. Those classified as definite or probable ADHF were included in the analysis; chronic, stable heart failure and hospitalizations not for heart failure were excluded. ADHF was further classified as heart failure with preserved (≥50%) or reduced (<50%) ejection fraction. Laboratory values were abstracted from the hospital record. Anemia was defined by WHO guidelines (< 12 g/dL for women; < 13 g/dL for men), using the lowest hemoglobin. Estimated glomerular filtration rate (eGFR) was calculated by the CKD-Epi formula using serum creatinine. Length of stay and mortality outcomes were analyzed by linear and logistic regression, respectively. All analyses were weighted to account for the sampling design and adjusted for race, age, sex, eGFR and smoking.
Results: Over four years, 13,554 (weighted) hospitalized events for definite or probable ADHF occurred, based on 2,804 sampled events. Comorbidities of ADHF included: hypertension (84%), coronary heart disease (55%), chronic bronchitis or COPD (34%), diabetes (48%), and chronic kidney disease (eGFR < 60 mL/min/1.73m2) (73%). Prevalence of anemia was 77% (95%CI: 75-79%) overall and did not differ by race (p=0.6), gender (p=0.1) or by subtype of heart failure based on preserved or reduced ejection fraction (p=0.09). Anemia was more common in patients over age 75 (80%; 95%CI: 78-83%) than patients aged 55-74 (73%; 95% CI: 70-76%); p<.0001. Anemia was associated with an increased length of stay by 3.6 (95%CI: 3.0-4.3) days, and with 1-year mortality (OR=1.3, 95%CI: 1.0-1.8). In a subset of ADHF hospitalizations (N=7,989; 59%) with two hemoglobin values, anemia prevalence was 84% (95%CI:82-86%) by the lowest hemoglobin, improving to 72% (95%CI: 70-75%) by the last documented hemoglobin. Anemia resolved over the course of the hospitalization for 15% of patients; more commonly for women than men (18% vs. 11%; p=.002).
Conclusion: Among patients hospitalized for ADHF in these 4 US areas, anemia was common, particularly for those over age 75, and was associated with a longer length of hospital stay and higher 1-year mortality.
- © 2013 by American Heart Association, Inc.