title: Long-term outcomes in a prospective cohort of apprentices exposed to high-molecular-weight agents.
abstract: BACKGROUND
  We conducted a long-term (8-yr) follow-up of 408 apprentices entering programs involving exposure to high-molecular-weight allergens.
  
  
  OBJECTIVE
  The objectives were to assess the frequency of new and persisting sensitization, symptoms, and bronchial hyperresponsiveness in relation with job history after ending apprenticeship and to examine characteristics significantly associated with the incidence and remission of these occupational outcomes.
  
  
  METHODS
  A respiratory symptom questionnaire, skin prick tests with work-related allergens (laboratory animals, flour, and latex), spirometry, and methacholine challenge were administered. The association between incidence or remission of these outcomes and individual characteristics at baseline and end of apprenticeship was examined.
  
  
  RESULTS
  In subjects who at any time during follow-up held a job related to their training (78%), the incidence of sensitization, rhinoconjunctival and chest symptoms, and bronchial hyperresponsiveness at follow-up was 1.3, 1.7, 0.7, and 2.0 per 100 person-years, respectively. The remission of these outcomes acquired during apprenticeship was 18.5, 9.6, 9.6, and 12.4 per 100 person-years, respectively, in subjects no longer in a job related to training. Several clinical, immunological, and functional characteristics at baseline and acquired during apprenticeship were found to be significantly associated with the incidence and remission of the outcomes.
  
  
  CONCLUSIONS
  The incidence of sensitization, symptoms, and bronchial hyperresponsiveness was lower while at work than during the apprenticeship period. A high proportion of subjects in a job not related to training experienced remission of symptoms acquired during apprenticeship.
authors.affiliation: Axe de Recherche en Santé Respiratoire, Sacré-Coeur Hospital, 5400 Gouin Blvd West, Montreal, Canada H4J 1C5. d.gautrin@umontreal.ca
authors.forename: Denyse
authors.initials: D
authors.lastname: Gautrin
authors.forename: Heberto
authors.initials: H
authors.lastname: Ghezzo
authors.forename: Claire
authors.initials: C
authors.lastname: Infante-Rivard
authors.forename: Michèle
authors.initials: M
authors.lastname: Magnan
authors.forename: Jocelyne
authors.initials: J
authors.lastname: L'archevêque
authors.forename: Eva
authors.initials: E
authors.lastname: Suarthana
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Malo
mesh_terms: D000293:Adolescent; D000328:Adult; D000485:Allergens / Q000276:immunology*; D001249:Asthma / Q000276:immunology* / Q000503:physiopathology / Q000517:prevention & control; D016535:Bronchial Hyperreactivity / Q000276:immunology*; D001985:Bronchial Provocation Tests; D005260:Female; D005500:Follow-Up Studies; D006306:Health Surveys; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000276:immunology* / Q000517:prevention & control; D008297:Male; D009784:Occupational Diseases / Q000276:immunology* / Q000517:prevention & control; D016273:Occupational Exposure / Q000009:adverse effects* / Q000517:prevention & control; D012220:Rhinitis / Q000276:immunology; D012882:Skin Tests; D017132:Workplace
chemical_list: D000485:Allergens