[Obstructive airway diseases and cigarette smoking].

The rate of uncomplicated bronchitis, obstructive bronchitis, obstructive emphysematous bronchitis, airways obstruction without bronchitis, emphysema, obstructive emphysema, and emphysematous bronchitis was determined in 300 patients. Assessment of smoking habits showed a ratio of non-smokers to smokers (smokers and ex-smokers) in uncomplicated bronchitis of 1 : 2, and in the various forms of obstructive lung disease of 1 : 1.41. Smoking, therefore, has a causative role in every third case of airways obstruction. The results support the view that smoking promotes the appearance of obstructive airways disease but that other additional or single factors such as infection and allergies probably have a more decisive role. Lung-function parameters in smokers and non-smokers, for the various forms of obstructive airways disease, are not affected differently.