Efficacy of treatment with N‐acetylcysteine inhalation for AECOPD: A propensity‐score‐matched cohort study

INTRODUCTION: N‐acetylcysteine (NAC) prevents acute exacerbations of chronic obstructive pulmonary disease (AECOPD). However, the value of NAC inhalation in the treatment of patients with AECOPD is still poorly understood. The study was conducted to evaluate the efficacy of NAC inhalation in AECOPD patients requiring hospitalization. METHODS: In this single institutional, retrospective cohort study, all patients with AECOPD requiring hospitalization between January 2021 and January 2022 were included. Patients were divided into NAC group and Non‐NAC group according to whether being treated with NAC inhalation and were matched using the propensity score. The primary outcome was a composite of progression to ventilation requirement, in‐hospital mortality and readmission for AECOPD within 30 days. The effect on the mean hospitalized days, blood gas indexes and the incidence rate of adverse drug events were compared between the two groups. RESULTS: Ninety‐six patients in the NAC group were matched with 96 patients in the Non‐NAC group. The differences in the primary composite end point (NAC group vs Non‐NAC group, 5.2% vs 16.7%; P = 0.011) were significant. The median time to discharge was shorter in the NAC group (8.3 vs. 9.1 days, P = 0.030). The NAC group presented a larger increase in partial pressure of arterial oxygen (P(a)O(2)) and a higher ratio of self‐reported symptomatic improvement from admission to day 5. There was no definite difference between the two groups in the frequency of adverse event. CONCLUSION: NAC inhalation is associated with an improved clinical outcome. A further study should be conducted to confirm the clinical usefulness of NAC inhalation in AECOPD patients.