Lifetime occupational exposure to dusts, gases and fumes is associated with bronchitis symptoms and higher diffusion capacity in COPD patients.

Esther Rodríguez,Jan-Paul Zock,Roel Vermeulen,David Donaire-González,Jaume Ferrer,The Pac-Copd Study Group ,Eduard Monsó,Ignasi Serra,Angel Gayete,Hans Kromhout,Judith Garcia-Aymerich,Josep M Antó,Jordi De Batlle,Eva Balcells,Marta Benet

doi:10.1371/journal.pone.0088426

Abstract

BackgroundOccupational exposure to dusts, gases and fumes has been associated with reduced FEV1 and sputum production in COPD patients. The effect of occupational exposure on other characteristics of COPD, especially those reflecting emphysema, has not been studied in these patients.MethodsWe studied 338 patients hospitalized for a first exacerbation of COPD in 9 Spanish hospitals, obtaining full occupational history in a face-to-face interview; job codes were linked to a job exposure matrix for semi-quantitative estimation of exposure to mineral/biological dust, and gases/fumes for each job held. Patients underwent spirometry, diffusing capacity testing and analysis of gases in stable conditions. Quality of life, dyspnea and chronic bronchitis symptoms were determined with a questionnaire interview. A high- resolution CT scan was available in 133 patients.Results94% of the patients included were men, with a mean age of 68(8.5) years and a mean FEV1% predicted 52 (16). High exposure to gases or fumes was associated with chronic bronchitis, and exposure to mineral dust and gases/fumes was associated with higher scores for symptom perception in the St. George’s questionnaire. No occupational agent was associated with a lower FEV1. High exposure to all occupational agents was associated with better lung diffusion capacity, in long-term quitters. In the subgroup with CT data, patients with emphysema had 18% lower DLCO compared to those without emphysema.ConclusionsIn our cohort of COPD patients, high exposure to gases or fumes was associated with chronic bronchitis, and high exposure to all occupational agents was consistently associated with better diffusion capacity in long-term quitters.

Highlights

Chronic obstructive pulmonary disease (COPD) is a leading cause of death, in developing countries [1] and is characterized by abnormal inflammatory response of the lungs to noxious particles and gases
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]
We studied a multicenter cohort of COPD patients recruited at their first hospital admission (PAC-EPOC Study) in order to test the hypothesis that occupational exposure to dusts, gases and fumes may be associated with worse lung function, measured by spirometry and diffusion capacity variables

Summary

Introduction

Chronic obstructive pulmonary disease (COPD) is a leading cause of death, in developing countries [1] and is characterized by abnormal inflammatory response of the lungs to noxious particles and gases. The effect of occupational exposure on the development or the characteristics of COPD has been studied in several cohorts. 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 associated with symptoms of bronchitis [5,7]. The effect of occupational exposure on other characteristics of COPD, especially those reflecting emphysema, has not been studied in these patients

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