The value of exhaled nitric oxide in assessing the risk of acute exacerbation and guiding the use of ICS in patients with COPD / 中国医师杂志

ABSTRACT

Objective:To explore the predictive value of exhaled nitric oxide (FeNO) for the risk of acute exacerbation in stable chronic obstructive pulmonary disease (COPD) patients over the next year and evaluate whether it can guide the use of inhaled corticosteroids (ICS).Methods:This study was a multicenter, retrospective and observational cohort study. The subjects of this study were stable COPD patients who were hospitalized in 12 hospitals in Hunan Province and Guangxi from January 2017 to December 2021. The patient′s basic Demography information, previous acute exacerbation history, pulmonary function, FeNO, chronic obstructive pulmonary disease assessment test questionnaire (CAT) score, modified British Medical Research Council dyspnea questionnaire (mMRC) score, chronic obstructive pulmonary disease control questionnaire (CCQ) score, and detailed treatment plan were collected. Based on FeNO 25 ppb, patients were divided into a high FeNO group and a normal FeNO group. All patients were followed up for 1 year and information on acute exacerbation was recorded.Results:A total of 825 patients were included, aged (63.5±9.1)years, with a median of 25 ppb of FeNO. A number of 825 patients were followed up for 1 year, of which 262(31.8%) experienced acute exacerbation. Multivariate logistic regression found that FeNO, CAT score, smoking cessation, and past history of acute exacerbation were independent factors predicting acute exacerbation in COPD patients in the next year (all P<0.05). High FeNO was a protective factor for acute exacerbation in COPD patients in the next year, with an OR value of 0.10 ( P<0.001). Further analysis found that the proportion of patients in the high FeNO group using ICS was significantly higher than that in the normal FeNO group [58.8%(247/420) vs 48.6%(197/405), P=0.003]. In the high FeNO group, using ICS can reduce the incidence of acute exacerbation of COPD in the next year [8.9%(22/247) vs 15.6%(27/173), P<0.05], while in the normal FeNO group, there was no statistically significant difference in the frequency of acute exacerbation between patients using ICS and those not using ICS ( P>0.05). Conclusions:FeNO is an independent factor predicting the acute exacerbation of COPD in the next year, and patients with high FeNO levels may consider using ICS in combination.