High volume hemodiafiltration in chronic hemodialysis patients: value of β2 microglobulin clearance in the quality control of the procedure

Abstract

Introduction: On line high volume hemodiafiltration (HVHDF) has shown to improve the clearance of medium molecules in dialyzed patients through high volumes of convection. Objective: The objective of this work is to evaluate the effectiveness of this technique in β2 microglobulin depuration, comparing its basal concentration, in chronic hemodialyzed patients, with the final concentration of the analyzed period. Further more, the KDQOL-SF was performed in order to evaluate the quality of life of the patients who participated in the study. Methods: Longitudinal cohort study of prevalent patients in highflux hemodialysis who were changed to on line high volume hemodiafiltration. Among other, β2 microglobulin clearance and its concentrations changes over time were measured as indicators of efficiency and adequacy of treatment. A statistical package Stata 11 was used. Results: Total follow up period was of 84 months (average 23,4 ± 19 months per patient). 8978 treatments were performed. Basal levels of β2 were; 36.05 mg/l ± 10, when admitted and 31.2 ± 10 (p=0.03), at the end of the study. Clearance mean of β2 was of 71 ± 16ml/min. The levels of β2 at the beginning of the study were associated with elapsed time from the first dialysis of the patients (r 0.4 – p< 0,02). Five years of conventional hemodialysis increase 11.2 mg/l the levels of β2 seric microglobulin and to obtain levels below 30 mg/l in 50% of our patients, 5 years of High Volume HDF is required. Conclusion: Values of β2 basal microglobulin in patients with chronic renal failure undergoing dialysis, are related to the time spent under hemodialysis treatment. In these patients, levels of seric β2 microglobulin, decrease slowly and progressively and reach clinical significance when the technique is high volume hemodiafiltration.