Abstract: 【Abstract】Objective To observe the effect of long-term hemodialysis (HD) combined with hemoperfusion (HP) on the clearance of protein bound uremic toxins and the quality of life in maintenance hemodialysis (MHD) patients. Methods A total of 36 MHD patients were randomly and equally divided into HD and HD+HP groups. Patients in HD group were treated with low-flux hemodialysis three times a week, while those in HD+HP group were treated with low-flux hemodialysis twice a week and hemodialysis combined with hemoperfusion once a week. They were followed up for 36 weeks. Urea clearance index (Kt/V) and the concentrations of protein bound uremic toxins including hippuric acid (HA), indoxyl sulphate (IS) and p-cresyl sulphate (PCS) were compared before and after the treatment. The Kidney Disease Quality of Life Short Form (KDQOL-SF1.3) scale was used to assess the quality of life. Result ①After the treatment for 36 weeks, HA and PCS had no statistical significances in HD group (HA: t=-0.328, P=0.747; PCS: t=-0.178, P=0.861) but decreased significantly in HD+HP group (HA: t=2.221, P=0.040; PCS: t=2.207, P=0.041) as compared with those before the treatment. HA and PCS were significantly lower in HD+HP group than in HD group (HA: t=2.139, P=0.045; PCS: t=2.051, P=0.048) at the end of the study. ②After the treatment for 36 weeks, IS was significantly higher (z=-2.298, P=0.035) in HD group but had no statistical difference in HD+HP group (z=- 0.970, P=0.332) as compared with that before the treatment. IS had no significant difference between the two groups (z=-1.485, P=0.137) at the end of the study. ③After the treatment for 36 weeks, bodily pain and vitality
scores, the two parameters of quality of life, were significantly lower in HD group (bodily pain: t=2.136, P=0.049; vitality: t=2.947, P=0.009), while dialysis related symptoms, effects of kidney disease and vitality scores were significantly higher in HD+HP group (dialysis related symptoms: t=-2.345, P=0.032; effects of kidney disease: t=-2.467, P=0.025; vitality: t=-2.315, P=0.034) as compared with those before the treatment. The effects of kidney disease, cognitive function, sleep, physical function, bodily pain, general health, social function and vitality scores were better in HD+HP group than in HD group (effects of kidney disease: t=-2.111, P=0.043; cognitive function: t=2.051, P=0.049; sleep: t=-2.062, P=0.047; physical function: t=-2.241, P=0.032; bodily pain: t=- 2.122, P=0.042; general health: t=- 2.374, P=0.024; social function: t=- 2.110, P=0.043; vitality: t=-2.560, P=0.015). Conclusion Long-term use of HD+HP is better than conventional HD in the removal of protein bound uremic toxins and the improvement of quality of life in MHD patients.

Key words: Protein bound uremic toxins, Hemoperfusion, Hemodialysis, Quality of life