The effect of occupational exposure on the development or the
characteristics of COPD has also been studied in several cohorts.
A variable degree of lung obstruction has been associated with
occupational exposure in patients with and without alpha-1-
antitrypsin deficiency [5–7]. In a more recent longitudinal study, a
decline in FEV1 over time has been described in early stages of the
disease [8] in association with fume exposure, while a crosssectional
study has shown COPD severity to be associated with
mineral dust exposure [7]. In several of these studies, occupational
exposure was also associated with symptoms of bronchitis [5,7].