LM Neas and J Schwartz
Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts 02115, USA.

Racial and gender differences in single-breath pulmonary diffusing capacity for carbon monoxide (DLCO) have previously received little attention. Between 1971 and 1975, the first National Health and Nutrition Examination Survey determined DLCO for 4,439 adults ages 25 to 74 residing in the United States, including 2,345 women and 438 blacks. The large sample permitted an evaluation of interactions and nonlinear relationships with DLCO, and its association with biomarkers of inflammation. In a model with separate race, sex, and smoking status intercepts, positive associations with FVC, height, weight, hemoglobin concentration, and negative associations with age and neutrophil count explained 59% of the variation in DLCO. In women, the decline in DLCO with age was much less than in men, but after age 47 the decline with age approached that seen in men. Blacks had lower DLCO levels (-1.96 ml/min/mm Hg, 95% confidence interval [CI] -0.77 to -3.14) with or without adjustment for FVC, but the changes in DLCO with age and height were similar in both races. Former smokers had lower DLCO (-1.13 ml/min/mm Hg, 95% CI -1.57 to -0.69), but this reduction was fully explained by the number of pack-years smoked. In current smokers, cigarettes per day and pack-years were predictive of DLCO even after control for FVC and controlling for these variables fully explained the difference in DLCO between never and current smokers. Peripheral neutrophil count, a biomarker of inflammation, was associated with reduced DLCO. Thus, substantial sex and race differences exist for DLCO within the general United States population.

This article has been cited by other articles:

				D. A. Zisman, A. S. Karlamangla, S. M. Kawut, O. A. Shlobin, R. Saggar, D. J. Ross, M. I. Schwarz, J. A. Belperio, A. Ardehali, J. P. Lynch III, et al. Validation of a Method To Screen for Pulmonary Hypertension in Advanced Idiopathic Pulmonary Fibrosis Chest, March 1, 2008; 133(3): 640 - 645. [Abstract] [Full Text] [PDF]

				D. Massaro, L. B. Clerch, and G. D. Massaro Estrogen receptor-{alpha} regulates pulmonary alveolar loss and regeneration in female mice: morphometric and gene expression studies Am J Physiol Lung Cell Mol Physiol, July 1, 2007; 293(1): L222 - L228. [Abstract] [Full Text] [PDF]

				J. Sprung, O. Gajic, and D. O. Warner Review article: Age related alterations in respiratory function - anesthetic considerations: [Article de synthese : Les modifications de fonction respiratoire liees a l'age - considerations anesthesiques] Can J Anesth, December 1, 2006; 53(12): 1244 - 1257. [Abstract] [Full Text] [PDF]

				D. Massaro and G. D. Massaro Toward Therapeutic Pulmonary Alveolar Regeneration in Humans Proceedings of the ATS, November 1, 2006; 3(8): 709 - 712. [Abstract] [Full Text] [PDF]

				D. Massaro and G. D. Massaro Estrogen receptor regulation of pulmonary alveolar dimensions: alveolar sexual dimorphism in mice Am J Physiol Lung Cell Mol Physiol, May 1, 2006; 290(5): L866 - L870. [Abstract] [Full Text] [PDF]

				M. Rizzi, M. Sergi, A. Andreoli, M. Pecis, C. Bruschi, and F. Fanfulla Environmental Tobacco Smoke May Induce Early Lung Damage in Healthy Male Adolescents Chest, April 1, 2004; 125(4): 1387 - 1393. [Abstract] [Full Text] [PDF]

				O. O. Aalami, T. D. Fang, H. M. Song, and R. P. Nacamuli Physiological Features of Aging Persons Arch Surg, October 1, 2003; 138(10): 1068 - 1076. [Full Text] [PDF]

				E. C. Kleerup, S. N. Koyal, J. A. Marques-Magallanes, M. D. Goldman, and D. P. Tashkin Chronic and Acute Effects of "Crack" Cocaine on Diffusing Capacity, Membrane Diffusion, and Pulmonary Capillary Blood Volume in the Lung* Chest, August 1, 2002; 122(2): 629 - 638. [Abstract] [Full Text] [PDF]

				I. Welle, P.S. Bakke, G.E. Eide, M.K. Fagerhol, E. Omenaas, and A. Gulsvik Increased circulating levels of {alpha}1-antitrypsin and calprotectin are associated with reduced gas diffusion in the lungs Eur. Respir. J., June 1, 2001; 17(6): 1105 - 1111. [Abstract] [Full Text] [PDF]

				A. A. Lone Respiratory Disorders of the Elderly Journal of Pharmacy Practice, August 1, 2000; 13(4): 297 - 307. [Abstract] [PDF]

				B. KOROTZER, S. ONG, and J. E. HANSEN Ethnic Differences in Pulmonary Function in Healthy Nonsmoking Asian-Americans and European-Americans Am. J. Respir. Crit. Care Med., April 1, 2000; 161(4): 1101 - 1108. [Abstract] [Full Text]

				I. WELLE, G. E. EIDE, P. BAKKE, and A. GULSVIK Applicability of the Single-Breath Carbon Monoxide Diffusing Capacity in a Norwegian Community Study Am. J. Respir. Crit. Care Med., December 1, 1998; 158(6): 1745 - 1750. [Abstract] [Full Text] [PDF]