Continued Spirometry Changes After Cessation of Exposure in Asbestos-Cement Workers

Objective: To assess further progression of spirometry parameters among former asbestos-cement plant workers. Methods: The following parameters were assessed: forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and the ratio (FEV1/FVC) using a linear regression model with mixed effects. Results: The analysis included 3005 individuals. Spirometrically defined restrictive ventilatory defects were registered in 21.6% of the patients, obstructive defects in 8.3%, whereas mixed changes in 7%. Current smokers had significantly lower levels of FEV1, FVC, and FEV1/FVC and a steeper decline compared with nonsmokers. More rapid progression was also observed along with increasing termination of exposure. Having higher exposure was associated with a slower decline in FEV1 and FEV1/FVC ratios. Conclusions: This report indicates that asbestos-cement workers with higher cumulative exposure still had lower mean levels of spirometric parameters, despite cessation of asbestos exposure many years ago.