Impaired Flow-mediated Dilation Is Associated with Low Pulmonary Function and Emphysema in Ex-smokers

• DOI: 10.1164/rccm.200707-980oc
• Publication Date: 2007-08-30T01:39:19Z
• Authors: R. Graham Barr; Sonia Mesia-Vela; John H. M. Austin; Robert C. Basner; Brad M. Keller; Anthony P. Reeves; Daichi Shimbo; Lori Stevenson
• Keywords: Pulmonary emphysema

Basic science research suggests a causal role for endothelial dysfunction in chronic obstructive pulmonary disease (COPD). Clinical studies examining function are lacking, particularly early the disease. Flow-mediated dilation (FMD) is physiologic measure of reactivity to endogenous nitric oxide.We hypothesized that lower FMD among former smokers would be associated with post-bronchodilator FEV(1), higher percentage emphysema using computed tomography (CT) and diffusing capacity.We measured FMD, function, CT random sample 107 cotinine-confirmed ongoing EMCAP study. was defined as change brachial artery diameter reactive hyperemia. Generalized additive models were used adjust potential confounders assess linearity.Mean age participants 71 +/- 5 years, 46% female, pack-years averaged 48 26. Mean 3.8 3.1%; mean 2.3 0.8 L; emphysema, 26 10%. A 1 SD decrease 132-ml (95% confidence interval, 16-248 ml; P = 0.03) decrement FEV(1) 2.6% 0.5-4.7%; 0.02) increase fully adjusted models. These associations linear across spectrum from normality disease, independent smoking history, also significant without COPD. Associations capacity consistent but nonsignificant (P 0.09). The FMD-FEV(1) association entirely attributable emphysema.Impaired by