Abstract: Objective  To investigate the effect of different frequency of hemodiafiltration combined with high flux hemodialysis (HFHD) in the treatment of patients with end-stage renal (ESRD) disease.  Methods  A total of 108 ESRD patients treated in Fujian Provincial Hospital from January 2019 to August 2022 were retrospectively studied. They were treated with hemodiafiltration combined with HFHD, and divided according to the frequency of hemodiafiltration into low frequency group (n=36, hemodiafiltration once per month), medium frequency group (n=36, hemodiafiltration twice per month), and high frequency group (n=36, hemodiafiltration thrice per month). The treatment lasted for 6 months. The adequacy of dialysis (including Kt/V, β2-microglobulin clearance rate and urea reduction rate), residual renal function (including urine volume, residual renal Kt/V and residual renal creatinine clearance rate), nutritional status (including serum total protein, prealbumin  and albumin), inflammatory factors (including interleukin-6, tumor necrosis factor-α and C-reactive protein), and complications were compared among the three groups.  Results  After 6 months of the treatment, the total urea clearance index (Kt/V), β2-microglobulin clearance rate, and urea reduction rate(URR) were statistically different among the three groups (F=33.410, 27.559 and 35.226 respectively; P＜0.001); residual renal function, urine volume, residual renal Kt/V, and residual renal creatinine clearance rate were different among the three groups (F=34.159, 27.911, 25.084 and 23.342 respectively;P＜0.001); serum total protein, prealbumin  and albumin, interleukin-6, tumor necrosis factor-α and C-reactive protein were also different among the three groups (F=28.404, 39.842, 25.968, 41.864, 25.074 and 39.240 respectively,P＜0.001); the incidence of complications was higher in the high frequency group than in the medium frequency and low frequency groups (χ2=8.826, P=0.012).  Conclusion  Different frequency of hemodiafiltration combined with HFHD can improve the dialysis adequacy, residual renal function, and nutritional status in ESRD patients, with the higher frequency of hemodiafiltration being more effective. It can also reduce the expression of inflammatory factors. However, the incidence of complications remains higher.

Key words: Hemodialysis filtration, High flux hemodialysis, Dialysis adequacy, Residual renal function, Nutritional status