Airways Obstruction From Asbestos Exposure: Residuals for Never Smokers
When men with pulmonary asbestosis with 30.6 years of asbestos exposure (column C), were compared with the unexposed men (column A), flows (FEVi, FEVi/FVC, FEF25-75, FEF75-85) and FVC were even lower and TLC and RV/TLC were higher and all differences were significant (C to A). Comparison of three asbestosis groups (Column C) to age-matched men exposed to asbestos for 28.8 years (mean) without radiographic asbestosis (column B) showed (nonstatistically significant) lower flows and FVC. The results of the mean residuals matched the comparison of means (as percent predicted) just described. Asbestos-exposed men compared with those not exposed to asbestos showed significant mean residual differences from predicted for midflows, terminal flows (FEF75-85) and TLC, which matched the differences shown for percentage of predicted (percent predicted) by t test (Table 3, top section).
Comparison of differences for men with pulmonary asbestosis to those without asbestos exposure showed that expiratory flows, FVC, and TLC were all significantly different (Table 4, top) and matched comparisons of percent predicted in Table 2. However, comparison of men with pulmonary asbestosis to age-matched asbestos-exposed men (Table 5, top) revealed that none of the residual differences was significant, just as was concluded from their comparisons as percent predicted in Table 2. asthma medications inhalers
Flows and FEVi were significantly lower and TLC was higher but FVC was not higher as compared with unexposed men (column A) in the 722 cigarette smokers who were asbestos exposed for 30.6 years (mean) but had no irregular opacities (column B, Table 2, middle block). All functions of current smokers with asbestosis (column C) were also significantly different from unexposed male smokers (column A). Furthermore, the pulmonary function values were significantly more abnormal in those with asbestosis (column C) compared with asbestos-exposed men (column B) except for midflow (FEF25-75) and RV/TLC. FEVi/FVC was significantly lower in asbestos-exposed men and asbestosis smokers but asbestosis did not increase effect over asbestos exposure. Current smokers showed significant additional functional impairment with the transition from asbestos exposed to asbestosis in contrast to nonsmokers.