Differences in pulmonary function related to smoking habits and race.

Three measures of pulmonary function, forced vital capacity, forced expiratory volume in 1 sec, and peak expiratory flow were studied in a population of 65,086 white, black, and Oriental cigarette smokers and nonsmokers, 20 to 79 years of age, who had had at least one Kaiser-Permanente Multiphasic Health Checkup between 1964 and 1968. The expected relationships with age and sex were noted for each of the racial groups. Whites showed markedly higher mean pulmonary function values than blacks and Orientals when the same age, sex, and smoking categories were compared. Important racial distinctions between smokers and nonsmokers were observed with respect to the 3 measures of pulmonary function. For whites, larger mean pulmonary function values were found among nonsmokers in comparison with cigarette smokers in virtually every age grouping and for both sexes. For blacks and Orientals, however, no such differences between smokers and nonsmokers were noted. The virtual absence of appreciable differences between...