Understanding COPD underdiagnosis in the post-COVID era

Introduction: COPD underdiagnosis remains a global concern, reaching 74.7% in Spain according to EPISCAN II. The COVID-19 pandemic collapsed many pneumology services from 2020 and onwards. We aimed to characterize COPD within our post-COVID follow-up and explore its underdiagnosis. Methods: We evaluated patients seen in our post-COVID follow-up between April 2020 and December 2022, and performed a descriptive analysis of their clinical and functional variables. We compared those with or without a previous diagnosis of COPD according to clinical history, and their most recent spirometry, defining COPD as a postBD FEV1/FVC<0.7). Results: From 473 patients, 287 (60.8%) were men and 186 (39.2%) were women with a mean±SD age of 65.3±13.2 and 65.3±14.6 yrs., respectively. Out of the total, 420 (88.8%) patients performed spirometry during follow-up. From those 420 patients, 31 (7.4%) had previous diagnosis of COPD according to clinical history, while 48 (11.4%) had COPD by spirometric criteria. Correct COPD diagnosis was 33.3%, underdiagnosis 66.6%, and overdiagnosis 4.0%. By gender, COPD underdiagnosis was 58.3% in women and 69.4% in men (p>0.05). We found significant differences (p<0.05) between COPD sub-populations (under-, over- and well- diagnosed), in the number of comorbidities (lower in underdiagnosed patients), and their characteristics (underdiagnosed had less smoking habit and lower pack-year index, among others). Conclusion: In our post-COVID follow-up 11.2% of patients were incorrectly diagnosed of COPD (either over- or underdiagnosed). Underdiagnosed patients had less comorbidities and less smoking. More comprehensive screening and diagnostic protocols for COPD are still needed, especially during the post-COVID era.