Reduction in β2-Microglobulin With Super-flux Vs. High-flux Dialysis Membranes

[Zach]

Reduction in β2-Microglobulin With Super-flux Versus High-flux Dialysis Membranes: Results of a 6-Week, Randomized, Double-blind, Crossover Trial

http://beta-2-microglobulin.blogspot.com/2008/07/reduction-in-2-microglobulin-with-super.html

Background
Uremic toxicity is a major concern in the dialysis population. There is keen interest in techniques that increase the removal of larger uremic molecules. We examined the short-term impact of a new, more porous, super-flux Helixone membrane (FX-E) versus the conventional high-flux Helixone membrane (FX-60) on β2-microglobulin (Beta 2 Microglobulin) reduction and nutritional and inflammatory parameters.

Study Design
Randomized, double blind, crossover, pilot trial.

Setting & Participants
A single freestanding dialysis center. 30 stable hemodialysis patients.

Intervention
Patients were treated with FX-60 and FX-E membranes for a treatment period of 6 weeks each, with a 2-week washout period in between.

Outcome & Measurements
Primary outcome was change in β2-microglobulin (Beta 2 Microglobulin) concentrations from baseline to end of treatment. Serum samples were obtained predialysis and postdialysis at 0, 2, and 6 weeks, and dialysate albumin samples were collected continuously throughout dialysis sessions.

Results
Mean postdialysis β2M concentrations at the end of 6 weeks of treatment were 6.73 mg/L for FX-E versus 8.22 mg/L for FX-60, which was significantly lower overall by 0.69 mg/L (95% confidence interval [CI], −1.09 to −0.29; P = 0.001). β2M reduction ratios were greater overall with FX-E by 4.83% (95% CI, 2.78 to 6.89; P < 0.001), with mean values of 57% for FX-60 versus 66% for FX-E at the end of treatment. Median dialysate albumin loss with FX-E was 1.23 g (range, 0.22 to 4.83 g) compared with 0.17 g (range, 0.0017 to 2.69 g) with FX-60, which was greater by 1.52 g (95% CI, 1.11 to 1.93; P < 0.001). Serum albumin concentrations were slightly lower with FX-E by 0.1 g/dL (0.55 g/L; 95% CI, −1.04 to −0.07; P = 0.03), but prealbumin concentrations were not significantly different at 8.53 mg/L (95% CI, −23.76 to 6.71; P = 0.3). There were no differences in inflammatory cytokine concentrations or small-solute removal.

Limitations
Short-term pilot study.

Conclusion
In this stable dialysis population, removal of β2-microglobulin (Beta 2 Microglobulin) was more efficient with the Helixone super-flux FX-E membrane, with only a small decrease in albumin concentrations despite increased albumin loss. Large trials with longer treatment periods are required to evaluate the impact of the FX-E membrane on clinical outcomes.

For entire study:

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6W9N-4S9NGDP-3&_user=10&_coverDate=07%2F31%2F2008&_alid=761451939&_rdoc=1&_fmt=high&_orig=search&_cdi=6687&_sort=d&_docanchor=&view=c&_ct=1314&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=d20056fb59d0e8abe791aa8d517dfbd1

[flip]

I remember reading about the new membrane several months ago. It's nice to see that they are moving forward with it.

[stauffenberg]

Now that longer-lasting dialysis is becoming more readily available with home hemodialysis, the key to improving the life expectancy and reducing the morbidity of dialysis patients further is developing filters that will remove the full range of molecules.  This is a step in the right direction.