EVALUATION OF THE UTILITY OF SPIROMETRY IN A REGIONAL PUBLIC-HEALTH SCREENING-PROGRAM FOR WORKERS EXPOSED TO WELDING FUMES

The objective of this study was to determine the usefulness of spirome try in the screening of chronic pulmonary problems related to exposure to welding fumes, in a regional public health-based screening program . Pulmonary questionnaires and spirometric tests were administered twi ce at 5-year intervals on 229 welders/cutters (mean age, 39.9 years) f rom 31 metal manufacturing plants. The baseline mean value at the firs t test for the forced expiratory volume in one second (FEV(1)) was 102 % of predicted, the forced vital capacity (FVC) was 107%, and the FEV( 1)/FVC ratio was 79%. The mean annual changes in the three spirometric indicators were -47 mt, -46 mt, and -0.3%, respectively. The usefulne ss of spirometry was assessed by looking at the relationship between e xposure to welding fumes and changes in spirometric indices, in multiv ariate linear regression analysis, accounting for age, height, and smo king. A high lifetime exposure to welding fumes was associated with be tter lung functions in the cross-sectional ap;broach (healthy worker e ffect) but not in the longitudinal approach, where no association was found. We concluded that the public health regional application of thi s screening program generated too many sources of variation fm spirome try to fulfill the objective of early detection of pulmonary function decline related to exposure to welding fumes. Based on these observati ons, we recommend that maintaining questionnaire screening, with spiro metry reserved as a second-line diagnostic intervention.