SOCIOECONOMIC-STATUS AND LUNG-CANCER INCIDENCE IN MEN IN THE NETHERLANDS - IS THERE A ROLE FOR OCCUPATIONAL EXPOSURE

Study objective - To evaluate the influence of occupational exposure t o carcinogens in explaining the association between socioeconomic stat us and lung cancer. Design - A prospective cohort study. Data on diet, other lifestyle factors, sociodemographic characteristics and job his tory were collected by means of a self administered questionnaire. Fol low up for incident cancer was established by record linkage with a na tional pathology register and with regional cancer registries. Setting - Population originating from 204 municipalities in The Netherlands. Participants - These comprised 58 279 men aged 55-69 years in Septembe r 1986. After 4.3 years of follow up there were 470 microscopically co nfirmed incident lung cancer cases with complete data on dietary habit s and job history. Measurements and main results - Estimation of occup ational exposure to asbestos, paint dust, polycyclic aromatic hydrocar bons, and welding fumes was carried out by two experts, using informat ion on job history from the baseline questionnaire. Socioeconomic stat us was measured by means of highest attained revel of education and tw o indicators based on occupation. In the initial multivariate analyses of socioeconomic status and lung cancer, adjustment was made for age, smoking habits, intake of vitamin C, beta-carotene and retinol, and h istory of chronic obstructive pulmonary disease or asthma. Additional adjustment for occupational exposure to the four carcinogens mentioned above did not change the inverse association between the level of edu cation and lung cancer risk (initial model: RR highest/lowest level of education =0.53; 95% CI 0.34,0.82; additional model: RR highest/lowes t level of education=0.53; 95% CI 0.34,0.84). Nor was the association between the two occupation based indicators of socioeconomic status an d lung cancer risk influenced by occupational exposure to carcinogens. The effect of occupational exposure on the association between the le vel of education and lung cancer risk did not differ between ex-smoker s and current smokers. Conclusions - Occupational exposure to asbestos , paint dust, polycyclic aromatic hydrocarbons, and welding fumes coul d not explain the inverse association between socioeconomic status and lung cancer risk. More research which explicitly addresses possible e xplanations for the association between socioeconomic status and lung cancer risk is needed.