The psychosocial work environment and health--what do we know and where should we go?

Background For more than 200 years, it has been known that exposure incurred during worklife can lead to increased cancer risk. In Switzerland, only mortality risks by occupation have been studied systematically so far. Five of the eight Swiss regional cancer registries, covering approximately 40% of the Swiss population, record the occupation for cancer patients systematically. Based on these incidence data, the current study presents an overview of cancer risk patterns by socioeconomic status and occupation in Switzerland. Materials and methods The study comprised all male patients ≥ 25 years of age with invasive cancer recorded in the cantons of Basel, Geneva, St Gall, Vaud, and Zurich. The study included 58 134 incident cancer cases for the period 1980-1993, the length of participation varying by registry. Because of the lack of concordance in both the definition and sources of information on occupation between the census and incident case data, population denominators were not available. Consequently, analyses were performed by the case-referent approach, considering the cancers of interest as cases and all other cancers as referents. The odd ratios for cancer were adjusted for age, registry, type of residence area, and nationality. Socioeconomic status was represented by an indicator based on the grouping of occupations by their alleged status. With the use of this indicator, socioeconomic variations in cancer risk and residual occupational variation after adjustment for socioeconomic status were calculated. Results and discussion by site Large socioeconomic differences in cancer risks were observed. Risks of tobacco- and alcohol-related cancers correlated negatively with socioeconomic status. On the contrary, risks of melanoma and other cancers of the skin, colon, prostate, testis, and kidney were associated with a high socioeconomic status. In general, adjustment for socioeconomic status attenuated the range of the occupation-specific risks. Farmers had the highest risk of lip cancer; indoor occupations typically showed a lower risk. This finding fits the actual knowledge on lip cancer etiology. Elevated risk for upper aerodigestive cancers was observed among workers with easy access to alcoholic beverages at the workplace, such as cooks, and generally also in occupations related to construction. Professionals and teachers showed a particularly low risk. After adjustment for socioeconomic status, increased risks appeared for artistic occupations. The higher risks of stomach cancer were observed for farmers and workers in the building and chemical industries. White-collar occupations typically showed lower risks. After adjustment for socioeconomic status, only the excess risk for chemical workers persisted. Slightly elevated risks for colon cancer were generally found for sedentary occupations, such as engineers, entrepreneurs, managers and teachers, in contrast to lower risks for farmers and construction workers. The highest risks for liver cancer were observed for workers in hotel and catering and for cooks and plasterers. Adjustment for socioeconomic status enhanced the elevated risk for dentists. Very high relative risks for sinonasal cancer were observed for leather workers, joiners, and cabinetmakers and, to a lesser extent, for turners.