Chronic obstructive pulmonary disease (COPD), which is characterized by obstruction to airflow that interferes with normal breathing, continues to challenge health care systems globally due to its high incidence of morbidity and mortality, imposing an enormous economic burden. This progressive disease, obstructing both large and small airways, results in a considerably impaired pulmonary function, poor quality of life and risk to exacerbate. People with moderate and severe COPD are particularly prone to exacerbations and the frequency of those exacerbations increases with the severity of the disease.