Effect of Intravenous N-acetylcysteine on Plasma Total Homocysteine and Inflammatory Cytokines During High Flux Hemodialysis

Abstract

Objective Hyperhomocysteinemia and increased inflammatory cytokines are independent risk factors in patients with renal diseases. N-acetylcysteine (NAC) is an antioxidant that is known to decrease inflammatory cytokines and plasma total homocysteine (tHcy). Therefore, the aim of this study was to compare normal saline injection with and without intravenous NAC during hemodialysis (HD) in terms of changes in serum levels of tumor necrosis factor-α (TNF-α, interleukin-10 (IL-10), high-sensitivity C-reactive protein (hs-CRP) and plasma tHcy. Patients and Methods In total, 43 high flux HD patients were enrolled at a 4-hour HD session and split into two groups, NAC ( n = 22) and NS ( n = 21) treatment groups, which received either a normal saline injection with intravenous NAC or without intravenous NAC, respectively. The NS group was divided into two subgroups, one with residual renal function ( n = 5) and the other with anuria ( n 16). The NAC group was also divided into two subgroups, one with residual renal function ( n 6) and the other with anuria ( n = 16). Serum TNF-α, IL-10, hs-CRP and tHcy were measured before and immediately after HD. Results There were no significant differences in baseline characteristics, TNF-α, IL-10, hs-CRP, and tHcy levels in intra- and intergroup comparisons. Compared to pre-HD baseline values, plasma tHcy level was lower after HD in the NS group ( p<0.001), NS with anuria subgroup ( p=0.001), NS with residual renal function subgroup ( p = 0.034), NAC group ( p < 0.001), NAC with residual renal function subgroup ( p < 0.001), and NAC with anuria subgroup ( p = 0.003). There were no statistically significant differences in plasma tHcy level when the NS group was compared with the NAC group. Plasma tHcy level was significantly lower in the NAC with residual renal function subgroup compared with the NS group ( p = 0.002), the NAC with residual renal function subgroup compared with the NS with anuria subgroup ( p<0.001), and the NAC with residual renal function subgroup compared with the NAC with anuria subgroup ( p = 0.001). Moreover, the reduction in plasma tHcy level during HD was greater in the NAC with residual renal function subgroup than in the NAC with anuria subgroup ( p = 0.001). Conclusion A normal saline injection is able to decrease plasma tHcy during high flux HD with or without NAC. However, a combination of the two further decreases plasma tHcy in high flux HD patients who still have residual renal function. NAC is only effective when there is residual renal function present to decrease plasma tHcy in high flux HD patients.