Abstract:Introduction Chronic obstructive pulmonary disease (COPD) is an increasingly serious global health problem that is associated with significant morbidity and mortality. The main pathological feature of COPD is the persistent limitation of respiratory airflow, which leads to fatigue, dyspnea and decreased physical activity. Dyspnea is a cardinal symptom of COPD and increases in severity as the course of COPD progresses. Therefore, the Global Initiative for Chronic Obstructive Lung Disease (GOLD) recommended in 2… Show more
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