Background Some COVID-19 survivors present lung function abnormalities during follow-up, particularly reduced carbon monoxide lung diffusing capacity (DLCO). To investigate risk factors and underlying pathophysiology, we compared the clinical characteristics and levels of circulating pulmonary epithelial and endothelial markers in COVID-19 survivors with normal or reduced DLCO 6 months after discharge. Methods Prospective, observational study. Clinical characteristics during hospitalization, and spirometry, DLCO and plasma levels of epithelial (surfactant protein (SP) A (SP-A), SP-D, Club cell secretory protein-16 (CC16) and secretory leukocyte protease inhibitor (SLPI)), and endothelial (soluble intercellular adhesion molecule 1 (sICAM-1), soluble E-selectin and Angiopoietin-2) 6 months after hospital discharge were determined in 215 COVID-19 survivors. Results DLCO was < 80% ref. in 125 (58%) of patients, who were older, more frequently smokers, had hypertension, suffered more severe COVID-19 during hospitalization and refer persistent dyspnoea 6 months after discharge. Multivariate regression analysis showed that age ≥ 60 years and severity score of the acute episode ≥ 6 were independent risk factors of reduced DLCO 6 months after discharge . Levels of epithelial (SP-A, SP-D and SLPI) and endothelial (sICAM-1 and angiopoietin-2) markers were higher in patients with reduced DLCO, particularly in those with DLCO ≤ 50% ref. Circulating SP-A levels were associated with the occurrence of acute respiratory distress syndrome (ARDS), organizing pneumonia and pulmonary embolisms during hospitalization. Conclusions Reduced DLCO is common in COVID-19 survivors 6 months after hospital discharge, especially in those older than 60 years with very severe acute disease. In these individuals, elevated levels of epithelial and endothelial markers suggest persistent lung damage. Supplementary Information The online version contains supplementary material available at 10.1186/s12931-022-01955-5.
【저자키워드】 DLCO, Post-COVID, Epithelial markers, Endothelial markers, Sequelae, 【초록키워드】 COVID-19, ARDS, Risk factors, severe COVID-19, acute respiratory distress syndrome, Hospitalization, Clinical characteristics, Pneumonia, severity, lung, spirometry, E-selectin, risk factor, hypertension, discharge, observational study, angiopoietin, Protease inhibitor, Protein, Characteristics, Survivors, Severity Score, Endothelial markers, pathophysiology, clinical, Pulmonary embolism, carbon monoxide, Prospective, Lung function, Patient, plasma, Follow-up, disease, epithelial, multivariate regression analysis, patients, Organizing pneumonia, Dyspnoea, Smokers, acute respiratory distress, marker, Plasma levels, lung damage, respiratory distress, acute disease, diffusing capacity, leukocyte, pulmonary embolisms, intercellular adhesion molecule, Adhesion Molecule, endothelial, Older, supplementary material, independent risk factors, hospital discharge, syndrome, circulating, independent risk factor, selectin, abnormality, SLPI, survivor, Cell, Occurrence, Result, elevated, reduced, suffered, individuals, Level, diffusing, endothelial marker, intercellular, 【제목키워드】 COVID-19, lung, plasma, marker, Endothelial cell, survivor, reduced, diffusing,