OBJECTIVES : In this study, we aimed to analyses the current evidence for the benefits of high-flux and low-flux haemodialysis.

METHODS : Searches were performed until February 2020 mainly using electronic databases for PubMed, Embase, Cochrane Library, CNKI and Wanfang. The randomized controlled trails, quasi-CRT which compared HFHD with LFHD in people with End-Stage Kidney Disease who required long-term hemodialysis are included. Data were extracted independently by two researchers for participants, interventions, risks of bias, and specific outcomes(e.g. all-cause mortality and cause-specific mortality, kidney function and related symptoms) among people on HD with assessment of risk of bias. Treatment effects were expressed as a risk ratio (RR) or mean different (MD)， with 95% confidence intervals(CI) using the random-effects model.

RESULTS : In total 33 studies were included that involved 6821 participants with ESRD. High-flux heamodialysis reduced all-caused mortality (8 studies,5443 participant: RR 0.89,95%CI 0.82-0.97）also reduced cardiovascular mortality (5 studies, 5048 participants: RR 0.83,95%CI 0.71,0.97). High-flux reduced pre-dialysis beta-2 microglobulin level(MD=-10.23 mg/L,95%CI -12.48mg/L), while included China studies for HFHD has presented post-dialysis beta-2 microglobulin level is also offer benefits (MD=-1.97 mg/L,95%CI -2.52,-1.42mg/L). The lipid profiles outcomes also shown great outcomes for HFHD. The Equilibrated Kt/V_urea has shown no difference between high-flux and lox flux groups (8studies, 2856 participants: MD=0.00, 95%CI -0.01,0.02).Insufficient data were available to reliably estimate the effects of different flux on subgroup participant that NCDs patients. The risk of bias was either high or unclear in the majority of studies.

CONCLUSIONS : The main outcomes(all-caused mortality, cardiovascular-disease mortality) have accordance with large well-designed RCT outcomes, mainly in the reason of better biometric index. However, further evidence from larger RCTs is needed to confirm that benefit of high-flux with respect to NCDs patients. It is also interested to explored that limited studies estimated outcomes in either pre-dialysis or post-dialysis (China Context) for beta-2 microglobulin level.