The Relationship between Endotypes and Exacerbation Events in COPD Patients

Introduction: Acute exacerbations of COPD are responsible for 60% of health costs, reduce patients' quality of life, and accelerate disease progression. COPD endotypes are expected to provide new insights about clinical phenotypic variability and therapeutic response between individuals through certain biomarker approaches. Objective: Our study aims to identify the relationship between COPD endotypes and exacerbation events. Methods: In this cross-sectional study design, participants with stable COPD (n=40) were recruited from the outpatient clinic at Airlangga University Hospital in March-August 2022. Blood was obtained for endotype's biomarker examination, such as α1-antitrypsin (AAT), IL-17A, neutrophil, and eosinophil count. The relationship between COPD endotypes and exacerbation events was analyzed using a non-parametric statistical test. Result: The lower limit normal of AAT levels obtained was 12.85ng/ml; 47.5% of subjects have low AAT levels. The average IL-17A levels and blood neutrophil counts were 0.478 ± 0.426 pg/ml and 5,916.95 ± 3,581.08 cells/μl, respectively. The average blood eosinophil count was 298.35 ± 280.44 cells/μl, 16 of 40 (40%) subjects with blood eosinophil count > 300 cells/μl. No significant association was observed between AAT levels (p = 1.000), IL-17A levels (p = 0.944), and blood eosinophil count (p = 0.739) with exacerbation events-only blood neutrophil count (p = 0.033) found to have a significant association with exacerbation events in COPD. Conclusion: AAT levels, IL-17A levels, and blood eosinophil count were not significantly related to exacerbation events in COPD patients. In comparison, blood neutrophil count was the only one associated considerably with exacerbation events. Further research about COPD endotypes is needed to identify exacerbation susceptibility as a precision treatment strategy.