[Risk factors in bladder cancer. A case-control study in the department of Hérault, France].

The excess of morbidity and mortality for cancers of the bladder in the french department of Hérault (South of France, on the side of the Mediterranean Sea) justified the implementation of a new epidemiologic study. A case-control study was designed, including 219 cases, 196 hospital-controls and 794 population controls. The collected information concerned profession, habits, behaviour (smoking, alcohol and coffee drinking), places of living, since childhood. The study confirms the role of tobacco, with a highly significant dose-effect, for total consumption, daily dose, and duration of consumption (p < 10(-4)). The classical risk of coffee is confirmed, but it seems not to be due to quantity of caffeine, but to the mouldered form of coffee. As far as alcohol is concerned, the sole risk is due to anisis beverages. When one considers the role of either tobacco, or coffee, or alcohol, the risk is strongly increased (p < 0.02) when exposure begins very early in life (childhood or teen age). But the effect does not depend on the beginning-of-exposure age, when the latter is posterior to teen age (p > 0.95). One may indeed think that the carcinogenic action of these factors concerns mainly the induction phase of the disease. Finally, when place of birth and place of living were considered, a North to South increasing effect was strongly suggested by the study.