Objective: The present study aims to identify occupational exposures associated with incidence of multiple myeloma (MM).
Methods: A population-based case-control study of MM (ICD-9 203) was conducted among Canadian males, with a total of 342 cases and 1506 controls contributing to the final analyses. Conditional logistic regression was used to estimate odds ratios (OR) and confidence intervals (CI), stratifying by age groups and province of residence.
Results: Based on the most parsimonious multivariable model, the following variables were significantly associated with an increased incidence of MM: exposure to coal dust (OR 1.7, 95% CI 1.2-2.4), long-held occupations as a carpenter (OR 3.2, 95% CI 1.4-7.1) or a machinist (OR 2.4, 95% CI 1.0-5.8); and immediate family member having been previously diagnosed with certain cancers (OR 1.4, 95% CI 1.1-1.8).
Conclusion: In this study of Canadian men, a higher risk of MM may be associated with exposure to coal dust, long-held occupations as a carpenter or machinist, and a positive family history of cancer.