Effect of N-acetylcysteine on exacerbations of bronchiectasis (BENE): a randomized controlled trial

BACKGROUND: N-acetylcysteine is a classic mucolytic agent. This study aimed to investigate the efficacy of N-acetylcysteine on reducing the risk of exacerbations in bronchiectasis patients. METHODS: A prospective, randomized, controlled trial was conducted between April 1, 2014 and December 31, 2016 in five general hospitals in Shandong Province, China. Adult bronchiectasis patients with at least two exacerbations in the past year were potentially eligible. Patients were randomly assigned to receive oral N-acetylcysteine (600 mg, twice daily, 12 months) or on-demand treatment. RESULTS: A total of 161 patients were eligible for randomization (81 to the N-acetylcysteine group and 80 to the control group). During the 12-month follow-up, the incidence of exacerbations in the N-acetylcysteine group was significantly lower than that in the control group (1.31 vs. 1.98 exacerbations per patient-year; risk ratio, 0.41; 95% CI, 0.17–0.66; P = 0.0011). The median number of exacerbations in the N-acetylcysteine group was 1 (0.5–2), compared with 2 (1–2) in the control group (U = − 2.95, P = 0.003). A total of 24.7% of the N-acetylcysteine group patients and 11.3% of the control group patients remained exacerbation-free throughout the 12-month follow-up (χ(2) = 4.924, P = 0.026). Compared with the control group, the volume of 24-h sputum in the N-acetylcysteine group was significantly reduced (t = − 3.091, P = 0.002). Additionally, the N-acetylcysteine group showed a significant improvement in the quality of life. No severe adverse events were reported in the intervention group. CONCLUSION: The long-term use of N-acetylcysteine is able to reduce the risk of exacerbations for bronchiectasis patients in Shandong Province, China. The results of this study should be verified in a larger randomized controlled trial. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02088216) (Registered date: March 5, 2014).