Effects of asbestos-related pleural disease on pulmonary function

The relationship between loss of pulmonary function and the presence of asbestos-related pleural disease was evaluated for 913 Minnesota asbestos workers. Asbestos-related pleural disease was categorized as circumscribed plaques or diffuse thickening. Compared with workers with normal pleura, workers with plaques had a decreased mean percentage for predicted forced vital capacity (FVC) and predicted forced expiratory volume in 1 s (FEV1.0). Diffuse thickening was associated with more profound decreases in FVC and FEV1.0. No relationship was seen between FEV % [(100 x FEV1.0)/FVC)] and either type of pleural disease. Dyspnea was associated with diffuse thickening more so than plaques. These results remained after control for pack-years of smoking, extent of parenchymal disease, and the presence of pulmonary disease history. Pleural plaques and diffuse pleural thickening were considered independent risk factors for the loss of lung function.