Aim: To examine the burden of respiratory symptoms, quality of life and co-morbid illness in COPD patients receiving maintenance treatment in a real world setting.
Methods: In a single visit, patients with a physician's diagnosis of COPD who were receiving monotherapy with a long-acting bronchodilator (LABD) performed spirometry, completed symptom questionnaires, and reported their treatments, history of exacerbations and co-morbidities.
Results: We enrolled 1084 patients of whom 1072 had acceptable spirometry. 689 (64%) had airflow obstruction (FEV1/FVC≤0.70) while 383 (36%) failed to meet spirometric criteria for COPD despite receiving maintenance therapy and having comparable symptoms and comorbid illness. Among those with confirmed COPD, dyspnoea was worse in those with more severe airflow limitation though exacerbation frequency was comparable across COPD stages.
Conclusions: COPD is commonly diagnosed and treated in patients without airflow obstruction. Many COPD patients receiving LABD monotherapy continue to suffer significant symptoms, exacerbations and poor quality of life.
Trial registration: ClinicalTrials.gov NCT00791518.