Anemia as a risk factor for cardiovascular disease in the Atherosclerosis Risk in Communities (ARIC) study

OBJECTIVES We investigated whether the presence of anemia is a risk factor for cardiovascular disease (CVD) outcomes in the general population. BACKGROUND Chronic anemia is a risk factor for CVD outcomes in patients with kidney disease and in patients with heart failure, but has not been evaluated as a risk factor in the general population. METHODS The Atherosclerosis Risk in Communities (ARIC) study was used to evaluate the relationship of anemia, defined by hemoglobin <13 g/dl in men and <12 g/dl in women, to CVD. Cox proportional hazards regression was used to adjust the relationship between anemia and CVD outcomes for other covariates in the entire study cohort, as well as in subgroups of men, women, African Americans and whites. RESULTS A total of 14,410 subjects (6,267 men and 8,143 women) without CVD at baseline had hemoglobin levels measured. Three hundred men (4.8%) and 1,058 women (13.0%) were anemic. During an average follow-up of 6.1 years there was a total of 549 (3.8%) CVD events. The presence of anemia was independently associated with an increased risk of CVD (hazard ratio [95% confidence interval] of 1.41 [1.01, 1.95]) in the entire study cohort. In subgroup analyses the hazard ratios were in the same direction, although not statistically significant in all cases. CONCLUSIONS Anemia is an independent risk factor for CVD outcomes in the ARIC cohort, a community cohort of subjects between the ages of 45 and 64 years. (C) 2002 by the American College of Cardiology Foundation.