Effectiveness of N-acetylcysteine for preserving residual renal function in patients undergoing maintenance hemodialysis: multicenter randomized clinical trial.

Abstract

To investigate the efficacy and safety of oral N-acetylcysteine (NAC) for preserving residual renal function in patients undergoing hemodialysis. Randomized, multi-center, parallel-group, open-label clinical trial (Registration No. IRCT 2014071418482N1). 54 patients who have been undergoing hemodialysis for at least 3months and had residual urine volume >100ml/24h were randomly allocated to NAC or no medication. Residual renal function evaluated by (1) estimated glomerular filtration rate (GFR), (2) 24h urine volume, and (3) renal Kt/V. GFR and Kt/V was determined at baseline and after 3months. 24h urine volume was measured at baseline, after 1, 2, and 3months. Intention-to-treat analysis was performed on 47 patients (NAC=26, control=21). GFR in patients receiving NAC improved, whereas in the control arm a decline of 1.0ml/min/1.73m2 was recorded (3.59 vs. 2.11ml/min/1.73m2, effect size=17.0%, p=0.004). For 24h urine volume, the between-group difference after 1month was significant (669 vs. 533ml/24h, effect size=15.4%, p=0.004). After 3months, 24h urine volume in the NAC arm was on average 137ml higher than in the control group, and the difference reached near significance (673 vs. 536ml/24h, p=0.072). In the follow-up visit, Kt/V was higher in the NAC arm but the difference did not reach statistical significance (0.81 vs. 0.54, p=0.152). Three months treatment with NAC appears to be effective in preserving renal function in patients undergoing hemodialysis and the medication is generally well-tolerated.