Background: Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are traditionally classified by healthcare utilization, a framework that may not reflect physiologic severity. The 2021 Rome Proposal introduced objective criteria for grading AECOPD, but North American data, including emergency department (ED)–treated patients, are limited. Research Questions: To determine the distribution of AECOPD severity using the Rome Proposal in a North American hospital cohort, characterize patients with mild events, and assess whether Rome-based grading predicts short-term readmissions among ED-treated patients. Study Design and Methods: We conducted a retrospective cohort study of 481 patients treated for AECOPD in a large tertiary hospital in Ontario, Canada, between January 2022 and September 2024. Events were reclassified as mild, moderate, or severe as per the Rome Proposal criteria (modified Medical Research Council score ≥ 2 substituted for dyspnea visual analog scale). Clinical characteristics and 1- and 3-month hospital representation were analyzed. Results: Overall, 49% of events were severe, 22% moderate, and 29% mild. Among hospitalized patients, 69% met criteria for severe AECOPD, whereas most ED-only events were mild (65%). Compared with moderate/severe events, mild events were associated with younger age, less home supplemental oxygen use, and higher mean forced expiratory volume in the first second. Among ED-treated patients, moderate/severe events were associated with significantly higher 3-month representation for AECOPD (31% versus 16%; mean 0.48 versus 0.18 visits per patient). Interpretation: Application of the Rome Proposal criteria substantially reclassified AECOPD severity and demonstrated meaningful clinical and prognostic discrimination, particularly in ED-treated patients. Keywords: chronic obstructive pulmonary disease, emergency department, hospitalization, Rome Proposal, severe acute exacerbations
Saint-Pierre et al. (Fri,) studied this question.