Occupational class, occupational mobility and cancer incidence among middle-aged men and women: a prospective study of the French GAZEL cohort*.

OBJECTIVE

To examine the association between occupational class, occupational mobility and cancer incidence in the 1990s.

METHODS

Prospective study of 14,853 men and 5493 women employed by a large French company. Incident cases (any cancer, smoking and alcohol-related, breast) were ascertained through a validated company-based cancer registry (1990-2002). Hazard ratios (HRs) by occupational class and by career-long occupational mobility were calculated adjusting for age, marital status, tobacco and alcohol consumption, weight, diet, asbestos exposure, family history of cancer, and reproductive history.

RESULTS

359 male cancers (107 smoking and alcohol-related) and 208 female cases (120 breast cancers) were observed. Male clerks and manual workers were at high risk, particularly of smoking and alcohol-related cancers (compared to managers, age-adjusted HRs: 2.95 95% CI 1.37-6.38 and 2.18 95% CI 1.15-4.11). Adjusting for specific health behaviors and other cancer risk factors reduced this gradient (fully-adjusted HRs respectively 1.95 95% CI 0.89-4.27 and 1.54 95% CI 0.80-2.97). The risk was also associated with occupational mobility. We found no association between women's occupational class and cancer.

CONCLUSION

The incidence of smoking and alcohol-related cancers among French men shows a strong socioeconomic gradient. Policies addressing these social disparities are needed.