Association of Pulmonary Function, Gut Microbiota, and Amino Acid Metabolism in COPD Patients.

Abstract

Chronic obstructive pulmonary disease (COPD) is characterized by progressive airflow limitation and systemic inflammation. Growing evidence suggests a link between gut microbiota alterations and metabolic dysregulation in COPD. Methods: A cross-sectional study included 20 COPD patients (mean age: 65.4 ± 8.3 years, 57% male). Pulmonary function was assessed using FEV₁, FEV₁/FVC, and residual volume. Gut microbiota composition was analyzed via 16S rRNA sequencing, and plasma citrulline and glycine levels were measured using LC-MS. Correlation analysis examined associations between lung function, microbiota composition, and amino acid metabolism.