Prevalence of self reported physician diagnosed asthma, chronic obstructive pulmonary disease (COPD) and asthma-COPD overlap syndrome

The joint distribution of asthma and COPD has not been well described in the general population. We studied the prevalence of self-reported physician-diagnoses of asthma, COPD and asthma/COPD overlap syndrome in the general population. In the Gene-Environment Interactions in Respiratory Diseases study, a postal screening questionnaire, which included questions on physician diagnosed asthma and COPD and respiratory symptoms, was administered in 4 Italian cities to random samples of subjects aged 20-44 (n=9739), 45-64 (n=3480) and 65-84 years (n=1975). The prevalence of diagnosed asthma decreased with age while that of COPD with or without asthma showed an opposite pattern (p Subjects with both asthma and COPD had the highest prevalence of respiratory symptoms (p Subjects with both the diagnoses of asthma and COPD represent a relevant clinical population with more severe and frequent exacerbations.