The Impact of Anemia of Chronic Disease on Chronic Obstructive Pulmonary Disease Patients

Hypothesis: The first part of the study is a survey on the prevalence of anemia of chronic disease (ACD) among COPD patients. The 2nd and 3rd part will test 2 null hypotheses (Ho): 1.serum inflammatory markers and plasma erythropoietin do not differ between COPD patients with and without ACD and 2. exercise capacity does not differ between COPD patients with and without ACD. Rationale-Aim: ACD is an immune driven disorder, developing in subjects suffering from chronic inflammatory diseases. COPD is a disorder very likely to be associated to ACD due to its systemic inflammatory dimension. Currently, data on the prevalence of ACD and on the level of inflammatory markers which are implicated in the pathogenesis of ACD in COPD subjects are limited and controversial. Furthermore, there is no data on the effect of ACD on exercise capacity of COPD subjects. Based to the aforementioned, this study has three goals: 1. to determine the prevalence and the epidemiologic characteristics of ACD in a population of clinical stable COPD patients 2. to investigate whether the levels of serum inflammatory markers and of plasma erythropoietin differ between COPD patients with ACD and without ACD 3. to determine potential differences regarding the aerobic exercise capacity between these two groups, using the cardiopulmonary exercise testing (CPET).