Abstract: Objective To explore the efficacy of high-flow nasal cannula oxygen therapy (HFNC) in the elderly patients with stable chronic obstructive pulmonary disease(COPD), as well as the expression level of serum progranulin (PGRN) and its significance. Methods A total of 96 elderly patients with moderate to severe stable COPD who were admitted to our hospital from June 2019 to June 2021 were selected and randomly divided into group A and group B. Group A was treated with HFNC, and group B was treated with bilevel positive airway pressure (BiPAP) ventilators. All the patients received expectorant, spasmolytic, anti-asthmatic and anti-inflammatory treatment at the same time. The levels of serum PGRN, interleukin-8 (IL-8), IL-6, tumor necrosis factor (TNF) -α and the blood gas parameters before and after treatment were detected and compared between the two groups. The correlations between PGRN and inflammatory factors were analyzed. Receiver operating characteristic curve(ROC)was drawn to analyze the value of PGRN in predicting the first acute exacerbation in the elderly patients with stable COPD. Results After treatment, the levels of serum PGRN, IL-8, IL-6, TNF-α and partial pressure of arterial carbon dioxide (PaCO₂) in two groups were significantly lower and partial pressure of arterial oxygen (PaO₂) was significantly higher than those before treatment, especially in group A (P<0.05). The difference in serum PGRN before and after treatment was positively correlated with the difference in IL-8, IL-6 and TNF-α in COPD patients (r= 0.724, 0.421, 0.322, P<0.05). The time of first acute exacerbation was statistically different between group A and group B (24 months vs 15 months,P<0.05). ROC analysis showed that the area under the curve (AUC) of difference of PGRN in predicting the first acute exacerbation in COPD patients was 0.717 (95%CI :0.619-0.812) and the cut-off value was 49.2 μg/L. According to the cut-off value, group A was divided into high-oscillation group and low-oscillation group, with a time of the first acute exacerbation of 27 months and 21 months, respectively (P<0.05). Conclusions HFNC has a good effect on the elderly patients with stable COPD, and the change level of serum PGRN during treatment is associated with the first acute exacerbation of the patients.

Key words: chronic obstructive pulmonary disease, high-flow nasal cannula oxygen therapy, serum progranulin, first acute exacerbation