Symptom burden and its associations with clinical characteristics in patients with COPD: a clustering approach

Background Symptom burden in patients with COPD is often under-recognised. In this cross-sectional analysis, we aimed to study the severity of a variety of (non-)respiratory symptoms in patients with and without COPD and to explore the associations between clusters based on symptom severity and other clinical characteristics. Methods Characteristics were assessed in 538 patients with COPD from primary, secondary and tertiary care and 116 non-COPD participants. The severity of 20 symptoms was measured using a visual analogue scale (VAS), ranging from 0 mm (no symptom) to 100 mm (maximum severity). K-means cluster analysis was applied to symptom severity in the patient sample only. Results People with COPD were comparable with non-COPD participants in terms of gender (58% versus 55% male, p=0.132) and age (64±9 years versus 63±6 years, p=0.552) and had a reduced forced expiratory volume in 1 s (57±23% predicted versus 111±17% predicted, p