Correlation of CT small airway measurement with clinical and inflammation factors in asthma patients

Abstract

Objective: To evaluate the correlation of CT small airway measurement with clinical and inflammatory factors in asthma patients. Methods: From November 2014 to December 2015, a total of 20 patients with asthma were recruited in outpatient department of Peking University Third Hospital. All underwent asthma control test (ACT), CT and pulmonary function test. Serum leptin, immunoglobulin E(IgE) and transforming growth factor-β1(TGF-β1), induced sputum eosinophil percentage(Eos%) and matrix metalloproteinase(MMP-9) results were collected.Using GE airway analysis software and adjusted by body surface area, luminal diameter(LD(adjusted)), luminal area(Ai(adjusted)), wall thickness(WT(adjusted)) and wall area%(WA%)at the end of 6th generation airway were recorded. Results: In asthma patients with smoking history, both LD(adjusted) and Ai(adjusted) were significantly lower than patients without smoking history(LD(adjutsed) (1.19±0.14)vs(1.34±0.11) mm, Ai(adjusted) (1.13±0.32) vs (1.43±0.24) mm(2,) t=-2.459, -2.267, all P<0.05); in asthma patients with induced sputum Eos%≥3%, both LD(adjusted) and Ai(adjusted) were significantly lower but WA% significantly higher than patients with induced sputum Eos%<3% (LD(adjutsed) (1.26±0.05) vs (1.44±0.09) mm, Ai(adjusted)(1.27±0.11) vs (1.66±0.17) mm(2,) WA%(83.96%±1.26%) vs (81.20%±2.26%), t=-3.935, -4.492, 2.448, all P<0.05). LD(adjutsed) and Ai(adjusted) had negative correlation with course of disease and induced sputum Eos%(LD(adjutsed) r=-0.512, -0.841, Ai(adjusted) r=-0.489, -0.841, all P<0.05), and positive correlation with FEV(1)/FVC and serum leptin(LD(adjutsed) r=0.669, 0.533, Ai(adjusted) r=0.681, 0.552, all P<0.05). Ai(adjusted) also showed positive correlation with FEV(1)%(r=0.452, P<0.05). WT(adjusted) and WA% were significantly negative correlated with FEV(1)/FVC and FEV(1)%(WT(adjusted) r=-0.621, -0.483, WA% r=-0.729, -0.548, all P<0.05). WA% also showed positive correlation with serum IgE and induced sputum MMP-9(r=0.509, 0.636, all P<0.05). CT airway indexes showed no significantly correlation with age, ACT scores and serum TGF-β1. Conclusions: CT airway indexes are found partially associated with course of disease, smoking history, serum leptin and IgE, induced sputum Eos% and MMP-9. CT airway indexes show correlation with FEV(1)/FVC and FEV(1)%.