Mean annual cost (€) per person of healthcare resources with 95%CI of the study population.

Group A: patients with at least one severe exacerbation of chronic obstructive pulmonary disease (E-COPD) in the three-year pre-index period; Group B: patients with only moderate E-COPD in the three-year pre-index period; Group C patients without E-COPD in the three-year pre-index period. The index event is not included.'Drugs used to treat COPD exacerbation. ''Drugs for obstructive airway diseases - Anatomical therapeutic Chemical (ATC) Classification R03 -. +Drugs for the cardiovascular system - ATC C -. ∼Pulmonary function tests, respiratory pattern examination, 6-minute walking test, chest computed tomography or radiography, C-reactive protein and sputum examination.