Abstract:Objective To investigate the level and clinical significance of serum miRNA-146a in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Methods 150 patients with AECOPD from January 2019 to December 2019 in Xixi Hospital of Hangzhou were selected as the AECOPD group, and 150 healthy physical examinees during the same period were selected as the control group. Reverse transcription polymerase chain reaction (RT-PCR) was used to determine the level of serum miRNA-146a. The serum C-reactive protein (CRP), procalcitonin (PCT) and interleukin-6 (IL-6) levels, as well as forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) were measured. Results The levels of serum miRNA-146a, CRP, PCT and IL-6 in the AECOPD group were higher than those in the control group (P < 0.05). The FEV1, FVC, and FEV1/FVC values of the AECOPD group were lower than those of the control group (P < 0.05). There were statistically significant differences in serum miRNA-146a levels between each two groups with different lung function grades (P < 0.05), and the serum level of miRNA-146a elevated with the increase of lung function grade. The serum miRNA-146a levels in death cases were higher than those in surviving patients (P < 0.05). The serum miRNA-146a levels in the AECOPD group were positively correlated with serum CRP (r =0.526), PCT (r =0.571), IL-6 (r =0.543) levels (P < 0.05), and negatively correlated with FEV1 (r =-0.532), FVC (r =-0.584), and FEV1/FVC (r =-0.561) (P < 0.05). Conclusions Serum miRNA-146a level in AECOPD patient is elevated, and the serum miRNA-146a level is closely related to the degree of inflammatory response, lung function, as well as condition and prognosis of the disease.