Risk estimates for chronic bronchitis in smokers: a study of male-female differences.

Data from a study of chronic bronchitis and obstructive airway disease prevalence in an urban population were used to obtain estimates of the risk of these diseases in smokers and to detail the effect of cigarette smoking on the observed male: female ratio of these diseases. Standard questionnaires and measures of pulmonary function were used. Eighty-two per cent of the observed prevalence of chronic bronchitis could be attributed to cigarette smoking, and 66% of the over-all population rate was attributed to smoking. Both men and women showed a linear increase in chronic bronchitis prevalence with increased smoking. The risk of chronic bronchitis was greater for men than women in all smoking categories, but no differences in decrease in pulmonary function could be observed. Data from comparable studies were assessed and were shown to corroborate the observation that men appear to be at a greater risk for chronic bronchitis, but less clearly so for obstructive airway disease. This excess risk does not appear to be due to a difference in cigarette consumption.