Original Investigation
Effect of dialysis membranes and middle molecule removal on chronic hemodialysis patient survival

https://doi.org/10.1016/S0272-6386(99)70311-2Get rights and content

Abstract

The type of dialysis membrane used for routine therapy has been recently shown to correlate with the survival of chronic hemodialysis patients. We examined whether this effect of dialysis membrane could be explained by differences in dialyzer removal of middle molecules using data from the 1991 Case Mix Adequacy Study of the United States Renal Data System. The sample analyzed included patients who had been treated by hemodialysis for 1 year or more, who were dialyzed with the 19 most commonly used dialyzers in 1991, and for whom delivered urea Kt/V could be calculated from predialysis and postdialysis blood urea nitrogen concentrations. Vitamin B12 (1,355 daltons) was used as a marker for middle molecules, and the clearance of vitamin B12 was estimated based on in vitro data. After adjustments for case mix, comorbidities, and urea Kt/V, the relative risk of mortality for a 10% higher calculated total cleared volume of vitamin B12 was 0.953 (P < 0.0001 v 1.000). Similar results were obtained when middle molecule removal was adjusted for body size. We conclude that both small and middle molecule removal indices appear to be independently associated with the risk of mortality in chronic hemodialysis patients. Differences in mortality when using different types of dialysis membrane may be explained by differences in middle molecule removal.

This is a US government work. There are no restrictions on its use.

Section snippets

Middle molecule removal

We have chosen vitamin B12 as the molecular marker for evaluating middle molecule removal for both historical and practical reasons. Vitamin B12 (1,355 daltons) has long been used as a marker for middle molecules in a number of in vitro and clinical studies,13 and manufacturers frequently report dialyzer clearances for vitamin B12 determined in vitro as a measure of the porosity of the dialysis membrane. Although the validity of projecting in vitro clearances of vitamin B12 to the clinical HD

Results

The primary results from these analyses are shown in Tables 2 and 3 where the relative mortality risk was calculated for higher rates of middle molecule removal as assessed by either TCVB12 or KB12 t/V, respectively.Table 2 shows that patients treated with a 10% higher calculated TCVB12 had an approximately 5% lower risk of mortality (RR = 0.953, P < 0.0001 v 1.000) when urea Kt/V remained constant. For comparison, patients treated with a 0.1 unit higher value of urea Kt/V had a 7.5% lower risk

Discussion

The results of the analyses performed in this study show that the use of a dialyzer with high calculated middle molecule removal rates is associated with a reduced risk of mortality in chronic HD patients independent of urea Kt/V. To minimize bias in these analyses, patients were excluded from the study sample when we could not accurately evaluate parameters that have been previously shown to influence patient survival, such as urea Kt/V. Furthermore, we excluded patients who had been on

References (39)

  • AK Cheung et al.

    Increased lipase inhibitor in uremia: Identification of pre-β-HDL as a major inhibitor in normal and uremic plasma

    Kidney Int

    (1996)
  • Z Makita et al.

    Reactive glycosylation endproducts in diabetic uraemia and treatment of renal failure

    Lancet

    (1994)
  • RA Odell et al.

    Beta2 -microglobulin kinetics in end-stage renal failure

    Kidney Int

    (1991)
  • WF Owen et al.

    The urea reduction ratio and serum albumin concentration as predictors of mortality in patients undergoing hemodialysis

    N Engl J Med

    (1993)
  • JI Tokars et al.

    National surveillance of dialysis associated diseases in the United States, 1991

    ASAIO J

    (1993)
  • F Dumler et al.

    Effect of dialyzer reprocessing methods on complement activation and hemodialyzer-related symptoms

    Artif Organs

    (1987)
  • DF Walton et al.

    Membrane biocompatibility

  • SM Orzol et al.

    Differences in the cost of hemodialysis by dialyzer membrane

    J Am Soc Nephrol

    (1996)
  • J Bergström et al.

    Clinical implications of middle and larger molecules

  • Cited by (143)

    • Hemodialysis adequacy

      2010, Chronic Kidney Disease, Dialysis, and Transplantation: A Companion to Brenner and Rector's The Kidney - Expert Consult: Online and Print
    • Hemodialysis Adequacy

      2010, Chronic Kidney Disease, Dialysis, and Transplantation
    • Survival with low- and high-flux dialysis

      2021, Clinical Kidney Journal
    View all citing articles on Scopus

    Received April 1, 1998; accepted in revised form July 31, 1998.

    Supported by USRDS, DVA Medical Research Funds and the Dialysis Research Foundation, Ogden, UT.

    Address reprint requests to John K. Leypoldt, PhD, Dumke Building 535, University of Utah, Salt Lake City, UT 84112. E-mail: [email protected]

    View full text