[Cigarette smoking and mortality among Japanese males in a prospective cohort study].

The relationship between smoking and disease was studied in a prospective cohort study among a Japanese male working population. The relative risk of cigarette smoking was positively associated with mortality for all diseases and major neoplasms. In current smokers consuming 25 to 34 cigarettes per day, relative risk for all diseases, major neoplasms, and lung cancer compared to nonsmokers was 1.38, 2.04, 2.36, respectively. These data suggest that there is a positive relation between smoking and disease mortality in this male working population. As for ex-smokers, estimated relative risk for all neoplasms was between that of current smokers and nonsmokers.