Abstract
Relationships between tobacco smoking and chronic laryngitis were investigated in 11,809 adults who received physical check-ups for laryngeal cancer at the Yokohama Municipal Cancer Detection Center. The majority of examinees were in their forties or older. The subjects were divided into three groups relative to smoking : non-smokers, smokers with a smoking index (SI) of less than 400 and smokers with SI of 400 or greater. SI was defined as the number of cigaretts per day multiplied by the duration of smoking in year. Of the 11,809 subjects, 5,888 were male and 5921 were female. One thousand five hundred and eleven males and 4,752 females were non-smokers, 1,125 males and 798 females were smokers with SI of less than 400, and 3,252 males and 371 females were smokers with SI of 400 or greater. Attention was focused on the incidence of chronic laryngitis, vocal fold polyp, Reinke's edema, leukoplakia and cancer. The pathologies were observed in 22 percent of the male and 7 percent of the female non-smokers, 37 percent of the male and 34 percent of the female smokers with SI of less than 400, and 51 percent of the male and 54 percent of the female smokers with SI of 400 or greater. The majority of the pathologies was chronic laryngitis in each group.
