Incidence and determinants of IgE-mediated sensitization in apprentices - A prospective study

We investigated prospectively the incidence and determinants of work-relate d specific skin sensitization in a cohort of 769 apprentices, including 417 in animal health technology, 230 in pastry-making, and 122 in dental-hygie ne technology. Subjects were recruited when starting exposure to laboratory animals, flour, or latex. A questionnaire and skin-prick tests with common and work-related allergens were administered on entry and at follow-up vis its from 8 to 44 mo; information on number of hours of exposure to specific allergens was obtained. Among 769 apprentices, 698 attended greater than o r equal to 1 follow-up visit. A total of 111 subjects developed specific se nsitization over the study period. The incidence of work-related sensitizat ion (per person-year) was 8.9% (95% CI 7.3 to 11.0%) in the animal-health p rogram, 4.2% (95% CI 1.8 to 8.2%) in the pastry-making program, and 2.5% (9 5% CI = 0.7 to 4.3%) in the dental-hygiene program. In the animal health gr oup, Cox regression analyses showed that atopy, nasal, and respiratory symp toms in the pollen season, and exposure assessed by the school attended or by duration of exposure to rodents were the most significant predictors of sensitization. In the dental-hygiene program, atopy and asthma were signifi cant determinants. This study shows that: (1) an apprenticeship in animal-h ealth technology carries a greater risk of developing specific sensitizatio n than do apprenticeships in pastry-making and dental-hygiene; (2) atopy, r espiratory symptoms in the pollen season, and number of hours in contact wi th rodents determine the risk of sensitization in apprentices in the animal health program.