Patient-reported respiratory symptoms and pre-bronchodilator airflow limitation among smokers in Switzerland.

Aims: To evaluate the prevalence and predictors of airflow limitation among smokers aged > or =40 years visiting primary care practices in Switzerland, and the correlation between airflow limitation and patient-reported symptoms.

Methods: General practitioners (GPs) were invited to participate in the study via letter. Airflow limitation was measured using an EasyOne spirometer without administration of a bronchodilator, and patient-reported symptoms were evaluated using an interviewer-administered questionnaire.