Coffee Intake, Smoking, and Pulmonary Function in the Atherosclerosis Risk in Communities Study.pdf

American Journal of Epidemiology Vol. 169, No. 12 ª The Author 2009. Published by the Johns Hopkins Bloomberg School of Public Health. DOI: 10.1093/aje/kwp068 All rights reserved. For permissions, please e-mail: journals.permissions@oxfordjournals.org. Advance Access publication April 16, 2009 Original Contribution Coffee Intake, Smoking, and Pulmonary Function in the Atherosclerosis Risk in Communities Study Jennifer A. Nettleton, Jack L. Follis, and Matthew B. Schabath Initially submitted December 15, 2008; accepted for publication February 23, 2009. Coffee contains polyphenolic antioxidants and caffeine, which may favorably affect pulmonary function. There- fore, the authors studied cross-sectional associations (1987–1989) between coffee intake and pulmonary function in the Atherosclerosis Risk in Communities Study, a population-based cohort study (analytic sample ¼ 10,658). They also conducted analyses stratified by smoking status, since smoking is a strong risk factor for respiratory disease and could influence the effects of caffeine and antioxidants. Self-reported coffee intake was categorized as rare/never, 7 cups/week, 1 cup/day, 2–3 cups/day, and 4 cups/day. Pulmonary function was characterized by the spirometric measures forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1). After adjust- ment for demographic factors, lifestyle characteristics, and dietary factors, pulmonary function values increased across increasing categories of coffee consumption in never and former smokers but not in current smokers. In never or former smokers who consumed 4 cups of coffee daily, FVC and FEV1 were 2%–3% greater than in never or former smokers who rarely/never consumed coffee