RT Journal Article
SR Electronic
T1 Incidence of probable occupational asthma and changes in airway calibre and responsiveness in apprentice welders
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 513
OP 518
DO 10.1183/09031936.03.00000903
VO 22
IS 3
A1 M. El-Zein
A1 J-L. Malo
A1 C. Infante-Rivard
A1 D. Gautrin
YR 2003
UL http://erj.ersjournals.com/content/22/3/513.abstract
AB The majority of cross-sectional studies have shown a higher prevalence of ventilatory impairment in welders while only few longitudinal studies were able to detect chronic effects on spirometry or bronchial responsiveness. The aim of the study was to determine the incidence of probable occupational asthma (OA), bronchial obstruction and hyperresponsiveness among 286 students entering an apprenticeship programme in the welding profession. This epidemiological prospective cohort study consisted of a baseline assessment survey and two follow-up assessments. A respiratory symptom questionnaire was administered at each visit. Spirometry and methacholine bronchial challenge test results, conducted once prior to onset of exposure and later after an average of 15 months of apprenticeship, were available for 194 subjects. The incidence of probable OA was ∼3% (6 of 194). The incidence of bronchial hyperresponsiveness, defined as a ≥3.2‐fold decrease in the provocative concentration causing a 20% fall in the forced expiratory volume in one second from baseline to the end of the study was 11.9%. A statistically significant difference was found between the baseline and end of study for the lung function values. In particular, the forced expiratory volume per cent predicted had significantly dropped by 8.4% on average. The significance of these early pulmonary function changes in relation to possible chronic effects of exposure to welding fumes and gases remains to be explored. This study was supported by L'Association Pulmonaire du Québec. M. El-Zein is a PhD student funded by the Max-Stern Recruitment Fellowship, McGill University and by the McAbbie Foundation Fellowship, Université de Montréal. D. Gautrin is a research scholar with the Fonds de la recherche en santé du Québec.