Daily symptom variability in patients with stable COPD in Brazil

Background: There are no studies reporting how respiratory symptoms vary throughout the 24-hour day in COPD patients in Brazil. Objective: To analyse 24-hour day variation of respiratory symptoms in stable COPD patients. Methods: Observational cross-sectional multicentric study in 8 centres in Brazil. Symptoms in the morning, at night and during the day were assessed the same as the Latin American Study of 24-hour Symptoms in Chronic Obstructive Pulmonary Disease (Miravitlles, M. et al. Respir Med 2018;134:62-69). Results: 593 COPD patients on regular treatment were included. 52.1% male, mean age 67.7 years, mean FEV1 49.4%, 15.5% active smokers and 17.2% comorbid asthma. 183 patients (30.8%) classified as severe symptoms in the daytime reported reduced level of physical activity (p=0.002), higher airflow limitation (p Conclusion: Dyspnea was more frequent in the morning than at night-time. The presence of COPD symptoms in the morning and/or at night-time was associated with the occurrence of severe symptoms in the daytime. Increased symptoms were strongly associated with worse quality of life and more frequent exacerbations, but weakly associated with airflow limitation.