Anemia in chronic obstructive pulmonary disease: epidemiology and economic implications

Abstract
Background: Anemia in chronic illness is associated with increased healthcare resource utilization (HRU) and costs. In COPD, it occurs frequently and influences both clinical and economic outcomes. Because no data studies have been performed either in a single center or a subpopula­tion of COPD patients, anemia's influence on the outcomes is not fully understood.Research design and methods: We conducted a retrospective cohort study in a large healthcare database to quantify prevalence, HRU and costs of anemia in COPD. From 1997 to 2005, patients ≥ 45 years of age with an ICD-9 diagnosis code for COPD and > 3.5 years of follow-up were included. Anemia was defined by the WHO criteria. Other disease states for which anemia is a known complication were excluded. We calculated the prevalence of anemia and compared annual HRU and costs between COPD patients with and without anemia. Multiple regression analysis adjusted for the effects of age, gender, race, length of enrollment, diagnosing physician spec...