Haemoglobin level and its clinical impact in a cohort of patients with COPD

¹ Bay Pines VAMC, Bay Pines, FL
² Ortho Biotech Clinical Affairs, LLC, Bridgewater, NJ
³ St. Elizabeth's Medical Center, Brighton, MA

^* To whom correspondence should be addressed. E-mail: Claudia.Cote{at}med.va.gov.

	Abstract

Haemoglobin (Hb) abnormalities in chronic obstructive pulmonary disease (COPD) are not well characterized. We investigated the prevalence and association of abnormal Hb with clinical outcomes.

Analysis of a prospective cohort of stable COPD outpatients (N=683) in a US Veterans Administration pulmonary clinic was undertaken. Patients were classified as anemic (Hb<13 g·dL^-1), polycythemic (Hb17 g·dL^-1, men and 15 g·dL^-1, women) or normal. We compared demographic characteristics and physiologic/functional outcomes between the groups. Regression models adjusting for confounders examined independent association of anaemia with clinical outcomes.

Anaemia was present in 116 (17%), and polycythemia in 40 (6%) patients. While the only values that differed between polycythemic and non-polycythemic patients were mean BMI and Hb, anemic patients had a significantly higher modified Medical Research Council (MRC) dyspnoea scale(2.8 vs. 2.6 points; p=0.04), lower 6-minute walk distance (6MWD) (265 vs. 325 meters; p<0.0001), and shorter median survival (49 vs. 74 months; p<0.01) than non-anemic patients. In regression models anaemia independently predicted dyspnoea and reduced exercise capacity.

Anaemia in COPD was an independent risk factor for reduced functional capacity. Polycythemia prevalence was low, and had no association with worsened outcomes. Further work is required to evaluate effect of anaemia correction on outcomes in COPD.

This article has been cited by other articles:

				P. J. Barnes and B. R. Celli Systemic manifestations and comorbidities of COPD Eur. Respir. J., May 1, 2009; 33(5): 1165 - 1185. [Abstract] [Full Text] [PDF]

				W. MacNee Update in Chronic Obstructive Pulmonary Disease 2007 Am. J. Respir. Crit. Care Med., April 15, 2008; 177(8): 820 - 829. [Full Text] [PDF]

				H. Watz, B. Waschki, C. Boehme, M. Claussen, T. Meyer, and H. Magnussen Extrapulmonary Effects of Chronic Obstructive Pulmonary Disease on Physical Activity: A Cross-sectional Study Am. J. Respir. Crit. Care Med., April 1, 2008; 177(7): 743 - 751. [Abstract] [Full Text] [PDF]

				A. Singh Is 13 g{middle dot}dL 1 the threshold to correct anaemia in COPD? Eur. Respir. J., November 1, 2007; 30(5): 1024 - 1025. [Full Text] [PDF]

				J. Tkac, S. F. P. Man, and D. D. Sin Review: Systemic consequences of COPD Therapeutic Advances in Respiratory Disease, October 1, 2007; 1(1): 47 - 59. [Abstract] [PDF]