Effect of N-acetylcysteine on Cochlear Function in Patients with Chronic Kidney Disease Undergoing Hemodialysis

Abstract

Objective: This study aimed to investigate the effect of N-acetylcysteine (NAC) on cochlear function in patients with chronic kidney disease (CKD). Methodology: The statistical population of this controlled clinical trial included all CKD patients. In total, 64 samples, selected from patients visiting the Dialysis Center of Al-Zahm Hospital from February 2017 to May 2017, were equally randomized into the intervention and control groups. At the baseline, the pure-tone audiometry (PTA) and Distortion Product Oto Acoustic Emissions (DP-OAE) tests were conducted. Then, NAC was administered in the intervention group for 8 weeks. Aforementioned hearing tests were repeated at the end of the interventions and results were compared. Finally, data analysis was carried out in SPSS. Results: Based on the mean scores of hearing threshold, there was no significant between-group difference in the speech discrimination score (SDS) speech reception threshold (SRT) of the left and right sides following NAC administration (P > 0.05). Comparison of the mean OAE following NAC administration showed a significant between-group difference, based on the mean signal/noise ratios (S/N 1000, 2000, and 4000) of the both right and left ears (P < 0.05). To compare the mean DP-OAE changes before and after the intervention between the two groups, the difference between pre- and post-intervention DP-OAE variables was first computed. Then, these changes were compared. A significant between-group difference was observed in S/N ratios of 1000, 2000, and 4000 Hz of the both right and left sides before and after the intervention (P < 0.05). In contrast, changes in other variables did not imply a significant between-group difference (P > 0.05). Conclusion: This study showed the effectiveness of NAC in improving cochlear function in 1, 2, and 4 KHz; whereas, it did not significantly affect the hearing threshold.