Determinants of restrictive lung function in asbestos-induced pleural fibrosis.
Schwartz-DA; Galvin-JR; Dayton-CS; Stanford-W; Merchant-JA; Hunninghake-GW
J Appl Physiol 1990 May; 68(5):1932-1937
Possible causes of restrictive lung function among persons with asbestos (1332214) induced pleural fibrosis were examined for 24 active or retired sheet metal workers with no x-ray evidence of lung parenchymal abnormalities. Seven subjects had radiologically normal pleura, nine circumscribed plaques, and eight had diffuse pleural thickening. Pulmonary function tests, bronchoalveolar lavage and high resolution computed tomographic (HRCT) scans of the lung parenchyma were conducted. Lavage fluid total and differential cell counts were obtained. All subjects were nonsmokers; most were former smokers. Subjects with diffuse pleural thickening had significantly decreased 1 second forced expiratory volumes (FEV1), forced vital capacity (FVC), and total lung capacity (TLC) compared to those with normal pleura. These subjects also had nonsignificantly decreased residual volume (RV) and carbon-monoxide transfer factors (DLcos). Subjects with circumscribed pleural plaques had nonsignificantly decreased FEV1s and FVCs relative to those with normal pleura. RVs and DLcos were similar in the two groups. After controlling for potential confounders, those with diffuse pleural thickening had significantly reduced FVCs, TLCs, and DLcos compared with subjects with normal pleura. Subjects with diffuse pleural thickening were more likely to have a significantly increased percentage of lymphocytes in their lavage fluid, indicative of lymphocytic alveolitis, and HRCT detectable parenchymal fibrosis. These parameters in subjects with circumscribed plaques did not differ significantly from those with normal pleura. After controlling for confounders, univariate analysis revealed that lymphocytic alveolitis was significantly associated with decreased FVC and TLC, but not with HRCT detected parenchymal fibrosis. Multivariate analysis indicated that circumscribed plaques or diffuse pleural thickening were the major factors involved in the decreases of lung volume and DLcos in these subjects.
NIOSH-Grant; Occupational-medicine; Metal-workers; Chest-X-rays; Asbestosis; Clinical-diagnosis; Visual-images; Clinical-techniques; Lung-fibrosis; Statistical-analysis; Pulmonary-function-tests
Internal Medicine University of Iowa Pulmonary Disease Division Iowa City, IA 52242
Pulmonary System Disorders
Journal of Applied Physiology
University of Iowa, Iowa City, Iowa