Summary
Background and objective: Health-related quality of life (HRQL) in respiratory diseases has been generally investigated in clinical settings, focusing on a single disorder. In this study on a general population sample, we assessed the relationship between HRQL and several respiratory diseases studied simultaneously (COPD, current (CA) and past (PA) asthma, allergic (AR) and non-allergic (NAR) rhinitis and chronic bronchitis (CB).
Methods: Controls (n=328) and cases of NAR (n=95), AR (n=163), CB (n=48), CA (n=224), PA (n=126) and COPD (n = 28) were recruited in the centre of Verona in the frame of the Italian multi-case control GEIRD (Gene Environment Interactions in Respiratory Diseases) study; HRQL was measured through the SF-36 questionnaire. The relationships between HRQL (in terms of Physical (PCS) and Mental Component Scores (MCS)), respiratory diseases, and covariates were evaluated.
Results: With respect to controls, the adjusted PCS median score was worse in subjects suffering from current asthma (− 1.7; 95%CI:-2.8;-0.6), CB (− 3.8; 95%CI:-5.7;-1.9), and COPD (− 5.6; 95%CI:-8.1;-3.1). MCS was worse in current asthmatics (− 2.2; 95%CI:-4.1;-0.3), CB (− 5.5; 95%CI:-8.7;-2.2), and COPD cases (− 4.6; 95%CI:-8.8;-0.5) as well.
Conclusions: To our knowledge, this is the first study in the general population that analyzed HRQL performing a simultaneous comparison of HRLQ in several respiratory disorders. We found that subjects suffering from COPD, CA, and CB had the poorest HRQL. Clinicians should carefully consider the possible impact of respiratory disorders as CB and not only that of CA and COPD.

Relevance
In the frame of the Gene Environment Interactions in Respiratory Diseases (GEIRD) survey, a multicase-control study in the general population, the aim of this paper was to assess the relationship between HRQL and COPD, asthma, CB, and rhinitis considered simultaneously.