[Prevalence of chronic bronchitis, asthma and airflow limitation in an urban-industrial area of Catalonia].

OBJECTIVES

To determine the prevalence of chronic bronchitis, asthma and airflow limitation in the general population of the urban-industrial area in and around the town of Sabadell (Catalonia, Spain), and to assess its degree of association with smoking and exposure to secondhand smoke.

METHODS

Transversal study of 642 men and women between 20 and 70 years of age listed on census rolls. The standardized questionnaire of the American Thoracic Society was used to interview 576 subjects (90%). Tests of forced spirometry with bronchodilation were administered to 497 individuals (77%).

RESULTS

The prevalence of chronic bronchitis was 11.6% (21% of men and 2.7% of women). Asthma had been diagnosed by a subject's doctor in 3.3% of the sample (2.1% of men and 4.4% of women). The prevalence of several asthma-related symptoms was higher. Dyspnea with wheezing was reported by 10.6% of the population (11.4% of men and 9.8% of women); wheezing within the past year was reported by 38.2% (45.4% of men and 31.4% of women). The prevalence of airflow limitation (defined as FEV1 < 80% with an FEV1/FVC index < 70%) in the population sample was 7.2% (10.4% of men and 4.1% of women); in men aged 60 to 70 years, however, the prevalence was 30.8%. Exposure to secondhand smoke was related to the presence of chronic coughing (OR = 4.6) and wheezing (OR = 1.8), but not to significant spirometric changes.

CONCLUSIONS

The prevalence of respiratory symptoms and airflow limitation is high in our area, particularly among men and older patients (60 to 70 years old). Like active smokers and ex-smokers, subjects who have been exposed to secondhand smoke are at greater risk of developing respiratory symptoms.