COPD symptoms/diagnoses and work exposure: a 20 years population-based survey

Background: work exposure to fumes/gases/chemicals is associated with COPD symptoms/diagnosis but few epidemiological surveys on general population samples estimated such relationship over a long time interval. Objectives: to assess the association between long term work exposure to fume/gas/chemicals and COPD symptoms/diagnosis over a 20 yrs period. Methods: a general population sample participated in 2 surveys carried out in Pisa in 1991-93 and 2009-11. A standardised questionnaire on health status and risk factors was used. Chi-square test was used to compare long term work exposure [ever exposed (EE), at least once exposed (ATOE), never exposed (NE)] and the change in COPD symptoms/diagnosis from the 1st to the 2nd survey (COPD symptoms: persistent/incident vs never/remittent; COPD diagnosis: persistent/incident vs never/remittent). Logistic regression models (LRM) were run to analyse the association between persistent/incident COPD symptoms/diagnosis and work exposure adjusted for gender, age, smoking habits, asthma symptoms/diagnosis at the 1st survey, smoking habits and lifetime passive smoke exposure. Results: there were 1107 longitudinal subjects: 27.5% EE, 30.4% ATOE and 42.1% NE. LRM showed a significantly higher risk of having persistence/onset of: COPD diagnosis (OR=2.4, 95%CI=1.4-3.9), dyspnoea (OR=2.0, 95%CI=1.4-2.9), usual phlegm (OR=2.2, 95%CI=1.5-3.3), usual cough (OR= 1.6, 95%CI=1.0-2.3), in EE; dyspnoea (OR=1.7, 95%CI=1.2-2.3), usual phlegm (OR=1.5, 95%CI=1.1-2.2) in ATOE. Conclusions: our findings indicate a longitudinal association between work exposure and COPD. There is a need for the EU to implement effective strategies for COPD prevention in work settings.