ObjectiveThrough measuring fractional exhaled nitric oxide (FeNO) and eosinophil levels of peripheral blood in chronic obstructive pulmonary disease (COPD) patients with different phenotype of acute exacerbation frequency, to predict the therapeutic effect of glucocorticoid therapy and guide the clinical treatment of different subtypes patients with acute exacerbations of COPD.MethodsA total of 127 patients with acute exacerbation of COPD in Suining Central Hospital from February 2017 to October 2019 were recruited. They were divided four groups according to the number of acute exacerbations in the past one year and the treatment scheme, ie. a frequent acute exacerbation with glucocorticoid treatment group (34 cases), a frequent acute exacerbation with non-glucocorticoid treatment group (31 cases), a non-frequent acute exacerbation with glucocorticoid treatment group (30 cases), and a non-frequent acute exacerbation with non-glucocorticoid treatment group (32 cases). FeNO value, eosinophil ratio in peripheral blood, COPD assessment test (CAT) score, and interleukin-8 (IL-8) concentration were measured before and on the 10th day of treatment, and the differences within group and between groups before and after treatment were compared.ResultsCAT score, FeNO, eosinophil ratio and IL-8 level in the four groups were significantly improved on the 10th day after treatment (all P<0.05). The declines of FeNO value, eosinophil ratio, and IL-8 level on the 10th day of treatment compared with those before treatment in the frequent acute exacerbation with glucocorticoid treatment group and the frequent acute exacerbations with non-glucocorticoid treatment group were larger than those in the non-frequent acute exacerbation with glucocorticoid treatment group and the non-frequent acute exacerbation with non-glucocorticoid treatment group (all P<0.05). The declines of FeNO value, blood eosinophil ratio and IL-8 level in the frequent acute exacerbation with glucocorticoid treatment group were also statistically significantly larger than those in the frequent acute exacerbations with non-glucocorticoid treatment group (all P<0.05). The improvement of CAT score in the frequent acute exacerbation with glucocorticoid treatment group was greater than that in other three groups (all P<0.05). There was no significant difference in CAT score between the non-frequent acute exacerbation with glucocorticoid treatment group and the non-frequent acute exacerbation with non-glucocorticoid treatment group (P>0.05).ConclusionsThe degree of airway inflammation is more obvious in patients with frequent acute exacerbation phenotype of COPD. FeNO value can reflect the level of airway inflammation in patients with frequent acute exacerbation of COPD and evaluate the response to glucocorticoid therapy.