Abstract
Occupational cohort studies conducted to study cancer incidence and mortality require extensive data gathering about workers’ job histories, exposures, and health outcomes. Although this process is expensive, the database created can be looked upon as a resource for broad investigations of the relationship between work and health. This paper presents the example of a retrospective cohort study which began in the traditional way, examining the link between a specific pesticide exposure and mortality and cancer incidence. The cohort register has since been used to investigate whether infertility, adverse reproductive outcomes, and childhood cancers might be associated with this exposure. It is also being used as the basis for studying other sawmill exposures including noise and wood dust, as well as socioeconomic factors including job strain, job mobility, unemployment, and retraining. This approach allows both the efficient use of occupational cohorts as well as providing the opportunity for investigators to develop a more comprehensive perspective on the determinants of the health status of workers and their families.
Résumé
Les études de cohortes professionnelles menées pour étudier la mortalité par cancer et l’incidence de cette maladie exigent que l’on rassemble un très grand nombre de données concernant les antécédents professionnels des travailleurs, leurs expositions aux risques, et les résultats en termes de santé. Bien que cela soit coûteux, on peut voir la base de données ainsi créée comme une ressource utile pour mener de vastes enquêtes sur les rapports qui existent entre le travail et la santé. Cet article présente le cas d’une étude de cohorte rétrospective qui a eu recours aux méthodes traditionnelles pour examiner le lien entre l’exposition à un pesticide spécifique et les taux de mortalité et d’incidence du cancer. Le registre de la cohorte a depuis servi à voir si l’infécondité, les issues défavorables en termes de reproduction et les cancers des enfants pouvaient être associés à cette exposition. On s’en est également servi pour étudier les risques posés par d’autres éléments auxquels on est exposé dans une scierie comme le bruit et la sciure de bois, ainsi que des facteurs économiques comme le stress dû au travail, la mobilité professionnelle, le chômage et le recyclage professionnel. Cette approche permet un meilleur recours aux cohortes professionnelles en plus d’offrir aux chercheurs la possibilité de développer une perspective plus complète sur les déterminants de l’état de santé des travailleurs et de leurs familles.
Footnotes
Sources of Support: Health Canada, National Health Research Development Program, Medical Research Council of Canada, Natural Science and Engineering Research Council, British Columbia Health Research Foundation, Workers’ Compensation Board of British Columbia, and Forest Renewal British Columbia
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