RESUMEN
Objective To explore the association of serum and sputum desmosine with treatment response in patients with chronic obstructive pulmonary disease(COPD). Methods Serum and induced sputum desmosine were measured with enzyme linked immunosorbent assay in 65 patients with newly diagnosed COPD and 26 healthy people. The associations of desmosine with pulmonary function ,modified Medical Research Council dyspnea scale(mMRC),and St. George's Respiratory Questionnaire score(SGRQ)were analyzed before and after treat-ment with inhaled corticosteroid/long acting β2-agonist. The relationship between desmosine and treatment re-sponse in COPD were explored. Results Level of sputum desmosine was higher in patients with COPD than in healthy controls(1061.2 ± 933.9 ng/mL vs. 443.5 ± 501.7 ng/mL;t=2.277,P=0.027). Sputum desmosine level was negatively related with forced expiratory volume in 1 second(FEV1)(r=-0.357,P=0.001)and forced vital capacity(FVC)(r =-0.479,P = 0.02). Serum desmosine level was correlated with pulmonary function,MRC, and SGRQ(P>0.05 for all comparisons). 3 months after treatment,neither serum nor sputum desmosine declined significantly(P>0.05). FVC,MRC,and the total scores and activity scores on the SGRQ improved more markedly in patients with lower expression of sputum desmosine than in those with higher expression(P < 0.05 for all com-parisons). Conclusions Level of sputum desmosine is inversely correlated with pulmonary function in stable COPD. Patients with lower expression of sputum desmosine have more significant improvement in symptoms.