The prevalence of chronic bronchitis, chronic airway obstruction, and respiratory symptoms in a Colorado city.

Abstract

A study of the prevalence of chronic respiratory disease symptoms in a random sample comprising one fifth of the adult population of Glenwood Springs, Colorado was conducted in the spring of 1967. Standard methods were used that permitted comparison of results with certain other studies. The high prevalence of chronic bronchitis was found to be strongly related to smoking, particularly of cigarettes, and was independent of age, sex, or history of dust exposure at work. Chronic airway obstruction was found to be predominantly a disease of elderly male smokers and increased in frequency with increasing age after 49 years. Male smokers with a history of dust exposure at work had a higher rate of chronic airway obstruction than smokers without such a history. The prevalence of nonobstructive chronic bronchitis did not change significantly with age in men whereas that of combined chronic bronchitis and chronic airway obstruction increased. Chronic airway obstruction without bronchitis increased with age in men older than 49. It was uncommon in women, regard· less of smoking habits. Exertional dyspnea was related to heart disease, increasing age, female sex, and smoking, but it correlated most strongly with spirometric evidence of airway obstruction. Wheezing was more common in male and female cigarette smokers, and hemoptysis was more common in male cigarette smokers than in nonsmokers. In all studies with which comparison was made, chronic bronchitis was strongly associated with smoking, but significant interstudy variation in prevalence was found both among smokers and nonsmokers, so that other factors might be of importance. More limited comparisons of the preva· lence of chronic airway obstruction showed a consistent relationship of this condition to smoking in men but not in women.