Diagnostic and therapeutic gaps in Chronic Obstructive Pulmonary Disease management and their associations with 1-year survival after hospitalisation for acute exacerbations.

INTRODUCTION AND OBJECTIVES: Chronic Obstructive Pulmonary Disease (COPD) remains a leading cause of morbidity and mortality globally. Acute exacerbations of COPD (AE-COPD) significantly worsen patient outcomes; however, COPD is frequently underdiagnosed and undertreated despite established guidelines.This study aimed to assess (1) the characteristics of patients hospitalised for a first episode of AE-COPD, (2) the differences between patients who had received guideline-recommended inhalation therapy prior to their first AE-COPD hospitalisation and those who had not, and (3) the associations between patient characteristics, pre-hospital inhalation treatment status and 1-year all-cause mortality following the index hospitalisation. METHODS: In this retrospective cohort study, 1855 consecutive patients admitted with clinically and spirometrically diagnosed AE-COPD to a secondary-level Swiss hospital between September 2016 and September 2024 were analysed. The primary outcome was 1-year all-cause mortality following the index hospitalisation. Survival was analysed using Kaplan-Meier estimates and Cox proportional hazards regression, with results reported as hazard ratios with 95% confidence intervals. RESULTS: Overall, 50.6% (n = 938) of patients lacked documented spirometric GOLD staging and 82.6% (n = 1533) had no recorded risk classification. Patients were stratified based on pre-admission use of long-acting inhalation therapy: Group 1 (no therapy, n = 834 [45.0%]) and Group 2 (therapy, n = 1021 [55.0%]). Baseline characteristics were largely comparable between groups; however, patients receiving long-acting inhalation therapy (Group 2) had significantly more patients with spirometrically confirmed COPD. During 1-year follow-up, 236 deaths (12.7%) occurred, in 133 of the 834 (15.9%) Group 1 patients and 103 of the 1021 (10.1%) Group 2 patients (log-rank p <0.001). In multivariable Cox regression analysis, no long-acting inhalation therapy (Group 1) as a variable was independently associated with higher 1-year all-cause mortality (adjusted HR: 1.95, CI: 1.48-2.56, p <0.001). CONCLUSION: Significant diagnostic and therapeutic gaps were observed in patients hospitalised for the first episode of AE-COPD. Guideline-recommended inhalation therapy prior to hospitalisation was independently associated with decreased 1-year all-cause mortality. Our findings suggest that guideline-recommended inhalation therapy reflects structured COPD care, earlier diagnosis and closer medical follow-up rather than a pharmacological effect alone. Hospitalisation for AE-COPD represents a critical opportunity to reassess the diagnosis and optimise long-term management, even within a well-resourced healthcare system.