Airway obstruction in relation to symptoms in chronic respiratory disease—a nationally representative population study

Abstract We examined the severity of airway obstruction and the occurrence of respiratory symptoms in a large, nationally representative population sample and in a subgroup of subjects with chronic bronchitis and/or emphysema to obtain information for developing national prevention and treatment strategies for these diseases. The study population comprised of 7217 randomly selected subjects (aged 30 years and older) who participated in a comprehensive health examination survey. The ‘cases' were subjects diagnosed as having chronic bronchitis and/or emphysema. The survey methods comprised of questionnaires, interviews, physical measurements, including spirometry, and clinical examinations. I…