Abstract: Objective To investigate the expression level and clinical significance of serum microRNA-181a ( miR-181a ) in patients with chronic obstructive pulmonary disease ( COPD). Methods Eighty patients diagnosed with COPD who were admitted to the respiratory department in Nanjing Brain Hospital from June 2019 to June 2021 were selected, and they were divided into the COPD group (38 cases, in stable stage) and the AECOPD group (42 cases, in acute exacerbation stage). Patients in the acute exacerbation stage were then divided into the good prognosis group (18 cases) and the poor prognosis group ( 24 cases) according to the prognosis. Another 40 healthy people who came to hospital for check-up were selected as controls. The qRT-PCR method was used to detect the expression level of serum miR-181a, and the pulmonary function test instrument was used to detect the lung function of the subjects. The correlation between the serum level of miR-181a and the lung function was analyzed by Pearson correlation analysis. COX regression analysis was used to analyze the risk factors that affected the poor prognosis of patients with AECOPD. Results The proportion of patients with smoking history and the level of miR-181a in the AECOPD group were higher than those in the COPD group and the control group, the FEV1 / FVC, FEV1 % , and FVC % in the AECOPD group were also lower than those in the COPD group and the control group. The results of Pearson correlation analysis showed that serum miR-181a expression level in AECOPD patients was negatively correlated with FEV1 / FVC, FEV1 % , and FVC % (P< 0. 05). Compared with the serum level of miR-181a in patients in the good prognosis group, tthat in the poor prognosis group was significantly higher (P < 0. 05). miR-181a level was an independent risk factor for the prognosis of AECOPD patients (P< 0. 05). Conclusion The expression level of serum miR-181a is related to the acute onset, disease progression and prognosis of COPD patients.

Key words: microRNA-181a, chronic obstructive pulmonary disease, lung function ,