Lung cancer: is there an association with socioeconomic status in The Netherlands?

STUDY OBJECTIVE To evaluate if there are differences in lung cancer incidence between socioeconomic groups in the Netherlands and if so, if smoking habits and other lifestyle characteristics could explain these differences. DESIGN Prospective cohort study. Baseline measurement included information on socioeconomic status, smoking habits, and other covariates by means of a self-administered questionnaire. Follow up was established by computerised record linkage to cancer registries and a pathology register. SETTING Population originating from 204 municipalities in The Netherlands. PARTICIPANTS 58,279 men aged 55-69 years in September 1986. After 3.3 years of follow up 490 microscopically confirmed incident lung cancer cases were detected. MAIN RESULTS An inverse association between lung cancer risk and highest level of education was found, which persisted after adjustment for age, smoking, dietary intake of vitamin C, beta-carotene and retinol (rate ratio (RR) highest/lowest level of education = 0.52, 95% CI 0.33, 0.82, trend p < 0.001). Men with a lower white collar profession had a significantly lower relative rate of lung cancer compared with blue collar workers (RR = 0.66, 95% CI 0.47, 0.96), but after adjustment for smoking habits this difference was reduced (RR = 0.73, 95% CI 0.51, 1.08). CONCLUSIONS There is an inverse association between highest level of education and lung cancer, which is still apparent after adjustment for age, smoking, dietary intake of vitamin C, beta-carotene and retinol. The significantly lower lung cancer risk of lower white collar workers compared with the risk of blue collar workers could be partially explained by smoking habits.