Medium Cut-Off Dialysis Membrane and Dietary Fiber Effects on Inflammation and Protein-Bound Uremic Toxins: A Systematic Review and Protocol for an Interventional Study

Abstract

The aim of this systematic review is to investigate the effects of the use of a medium cut-off membrane (MCO) and dietary fiber on the concentration of protein-bound uremic toxins (PBUTs) and inflammatory markers in hemodialysis (HD) patients. Of 11,397 papers originally found, eight met the criteria of randomized controlled trial design. No study examined the effects of MCO membranes on PBUTs. Three studies examined the reduction in inflammatory markers with MCO membranes compared to high-flux HD membranes and showed no significant differences. Five studies of dietary fiber supplementation showed an inconclusive positive effect on PBUT levels and a significant positive effect on the reduction in inflammatory markers (interleukin-6 reduction: standardized difference in means −1.18; 95% confidence interval −1.45 to −0.9 for dietary fiber supplementation vs. control; p < 0.001). To date, no study has combined the use of an MCO membrane and fiber supplementation to reduce PBUT levels and inflammation with online hemodiafiltration as a comparator. A rationale and protocol for an interventional trial using a combination of MCO membrane dialysis and fiber supplementation to lower inflammatory markers and PBUT concentrations are presented.

The effects of dietary fiber on common complications in critically ill patients; with a special focus on viral infections; a systematic reveiw

“…It was reported that improving the gastrointestinal flora through receiving DF may prevent severe inflammatory responses in patients with viral infections by maintaining the function of the immune system at the optimum level 15 . So that increased fiber intake was significantly associated with lower odds of having an elevated C‐reactive protein concentration and a positive effect on the interleukin‐6 reduction when compared with the lowest intake 31–33 …”

“… 15 So that increased fiber intake was significantly associated with lower odds of having an elevated C‐reactive protein concentration and a positive effect on the interleukin‐6 reduction when compared with the lowest intake. 31 , 32 , 33 …”

“…15 So that increased fiber intake was significantly associated with lower odds of having an elevated C-reactive protein concentration and a positive effect on the interleukin-6 reduction when compared with the lowest intake. [31][32][33] The SCFAs including butyrate, acetate, propionate, which are produced through bacterial fermentation of DF in the colon, 34 have independent beneficial roles in gut defense against viruses, production of secretory immunoglobulin A, and anti-inflammatory responses. 35 SCFAs also may inhibit nuclear factor kappa light chain enhancer of activated B cells (NFкB) activity through activating of G protein-coupled receptor (GPR) 41 and 43, and exert some anti-inflammatory effects through reduced neutrophil migration, decreased production of proinflammatory cytokines, and decreased adhesion molecule expression.…”

Efficacy of medium cut‐off dialyzers and comparison with high‐flux dialyzers in patients on maintenance hemodialysis: A systematic review and meta‐analysis

“…Better removal of these molecules can be obtained by using large pore membranes with added increased convection by MCO dialyzers. While Heric et al reviewing three studies, indicated that the reduction in inflammation markers (e.g., IL‐6, TNF‐α, and CRP) is not statistically different between the MCO dialyzers groups and HF dialyzers groups [42]. Further research is needed to explore the impact of MCO dialyzers on inflammatory cytokines as compared with HF dialyzers.…”

New Strategies for the Reduction of Uremic Toxins: How Much More We Know

“…However, the authors concluded by emphasizing that blood purification strategies used alone are not sufficient and future directions should include a synergic approach by reducing PBUTs production in the upstream and increasing their clearance in the downstream [13,14]. The same concept was supported by Eric and coworkers [15], who, after a systematic review on the effects of the use of a medium cut-off membrane (MCO) and dietary fiber on the serum level of PBUTs and inflammatory markers in HD patients, presented a protocol for an interventional trial using a combination of the two, namely MCO membrane dialysis and fiber supplementation.…”