Assessing COPD profiles and outcomes by dyspnoea severity

Introduction: Dyspnoea is one of the most common symptoms in chronic obstructive pulmonary disease (COPD) and has been associated with poor clinical outcomes. Aims and objectives: To investigate relationships between dyspnoea severity, baseline characteristics and outcomes in patients with COPD. Methods: Data from two 1-year, randomized trials (NCT00168844; NCT00168831) of tiotropium Respimat® 5 µg and placebo were pooled. This retrospective analysis assessed characteristics and outcomes of patients by Baseline Dyspnea Index score. Results: Of 1317 patients, 337 (26%) had mild or no dyspnoea at baseline, 743 (56%) moderate dyspnoea and 237 (18%) severe dyspnoea (Table). Baseline demographic characteristics were similar across dyspnoea categories. However, higher levels of dyspnoea correlated with more advanced COPD (GOLD Stage), and greater use of short-acting bronchodilators and inhaled corticosteroids. Patients with severe dyspnoea reported more exacerbations within the past year. Increasing dyspnoea at baseline correlated with greater risk of moderate–severe (P=0.0005) and severe (P=0.0198) exacerbations during the study. Tiotropium reduced moderate–severe exacerbation risk and significantly improved FEV1 and FVC across all dyspnoea categories. Conclusions: Patients with more severe dyspnoea had more advanced COPD, and a higher risk of exacerbation. Tiotropium improved outcomes regardless of baseline dyspnoea severity.