Red cell macrocytosis in COPD patients without respiratory insufficiency: a brief report

Red cell macrocytosis has been frequently described in hypoxemic patients with chronic obstructive pulmonary disease (COPD). However, macrocytosis is not related to hyoxemia. The objective of this study was to determine the frequency of macrocytosis (defined as mean corpuscular volume (MCV) higher than 94fl) in stable COPD patients without respiratory insufficiency, and to analyze the possible relationship between its presence and clinical and functional parameters. Fifty-eight consecutive patients with COPD, and without other significant comorbid conditions, were included in the study. Macrocytosis was present in 17 of the 58 stable COPD patients (29%). The differences between patients with and without macrocytosis were not statistically significant, except for MCV. In the subgroup of 36 ex-smoker COPD patients, macrocytosis was present in nine patients (25%). In this subgroup, MCV significantly correlated with dyspnea (r=0.36, P=0.03) and forced expiratory volume in 1s (FEV(1)) (r=-0.35, P=0.03). We conclude that macrocytosis is a frequent finding in stable non-hypoxemic COPD patients, and that in ex-smoker patients the degree of macrocytosis is associated with a worse clinical situation in terms of dyspnea and FEV(1).