RT Journal Article
SR Electronic
T1 Inter-relationship of different types of respiratory symptoms in COPD
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP P3598
VO 44
IS Suppl 58
A1 Paul W. Jones
A1 Marc Miravitlles
A1 Ferran Chuecos
A1 Esther Garcia Gil
A1 Rosa Lamarca
YR 2014
UL http://erj.ersjournals.com/content/44/Suppl_58/P3598.abstract
AB AimTo examine the relationship between respiratory symptoms and their consistency across subgroups.MethodsData were analysed from two, 6-month aclidinium/formoterol combination studies. Respiratory symptoms were assessed by the Exacerbations of Chronic Pulmonary Disease Tool-Respiratory Symptoms (E-RS), the Early Morning Symptoms of COPD questionnaire and the Nighttime Symptoms of COPD questionnaire. The latter both evaluate individual symptoms (cough, wheezing, shortness of breath and difficulty bringing-up phlegm) and have an overall COPD symptoms item; also assessed were: limitation to activity (morning) and nocturnal awakening due to COPD (nighttime). Subgroups tested were sex, age, smoking status, severity of airway obstruction (postbronchodilator FEV1/FVC <70 and FEV1 ≥50% predicted or postbronchodilator FEV1/FVC <70 and FEV1 <50% predicted) and GOLD group. A principal-components factor analysis was used with factor rotation.ResultsThe worst scores were: breathlessness, and early morning and nighttime cough and breathlessness. Two factors account for 83% of variance (F1: 72%; F2: 11%). F1 consisted of wheezing, breathlessness, overall COPD symptoms and limitation of activity; F2 contained cough and phlegm. Morning, daytime or night symptoms always loaded onto the same factor. Subgroups had the same pattern except GOLD A and C. In GOLD A, F1 (60% variance) was driven by cough and phlegm, and F2 (16% variance) by breathlessness. In GOLD C, F1 (57% variance) consisted of breathlessness, wheezing and awakenings; F2 (16% variance) contained cough and overall COPD symptoms.ConclusionsMost COPD symptoms, regardless of time of day, group into a single factor; cough and phlegm form a second factor.