Reflection of passive exposure to smoking in the home on the prevalence of chronic bronchitis in non-smokers.

Analysis of data assembled in an epidemiological investigation of 123 235 adults from three districts of the West Bohemian region incl. 57 217 male non-smokers from a total of 66 806 and 23 473 male non-smokers from a total number of 56 429 males revealed a high significant (p less than 0.005) rise in the prevalence of symptoms of chronic bronchitis in subjects exposed passively to smoking in the home. Exposure to other adverse factors increased the prevalence approximately three times in both sexes. The effect of passive exposure to smoking was, however, manifested far more in men. No reason was found in the investigated data for the interpretation of these differences. It appears that the cause could be the different behaviour of smokers to non-smokers in the home, where the smoker-husband usually is considerate to his non-smoker wife during her pregnancy and child care, while in women smokers this motivation is lacking.