Agreement between different parameters of dialysis dose in achieving treatment targets: results from the NECOSAD study

Nephrol. Dial. Transplant. (2011) - doi: 10.1093/ndt/gfr396 – First published online: August 4, 2011

By Karin E. Moret1, Diana C. Grootendorst2, Friedo W. Dekker2, Elizabeth W. Boeschoten3, Raymond T. Krediet4, Saskia Houterman1, Charles H. Beerenhout1, Jeroen P. Kooman5 and and the NECOSAD Study Group*

Author Affiliations: 1 Department of internal medicine, Máxima Medical Centre, Veldhoven, Leiden, The Netherlands2 Department of Clinical Epidemiology Leiden University Medical Centre3 Hans Mak Institute, Naarden, The Netherlands 4 Department of Nephrology, Amsterdam Medical Centre, Amsterdam, The Netherlands 5 Department of internal medicine, University Hospital Maastricht, The Netherlands

Submitted by Mr CS Soong

Abstract

Background.

The recommended parameter of dialysis dose differs between K-DOQI and the European Best Practice Guidelines. It is not well known to what extent an agreement exists between the different parameters, nor if target and delivered dialysis dose are prescribed according to the urea reduction rate (URR), single-pool Kt/V (spKt/V) or equilibrated double-pool Kt/V(eKt/V) and which parameter is most strongly related to mortality

Methods.

In 830 haemodialysis patients from the NECOSAD cohort URR, spKt/V and eKt/V were calculated and compared according to a classification regarding the recommended treatment targets (70%, 1.4 and 1.2, respectively) as well as minimum delivered dialysis dose (65%, 1.2 and 1.05, respectively). Moreover, the relation between treatment dose and survival was assessed using Cox regression analysis.

Results.

A spKt/V of ≥1.4 and URR ≥70% corresponded with eKt/V ≥1.20 (as reference method) in, respectively, 98.0 and 90.6% of patients. spKt/V of≥1.2 and URR ≥65% corresponded with eKt/V ≥1.05 in, respectively, 95 and 91.2% of patients. Deviations from the reference method were significantly related to differences in urea distribution volume (spKt/V), treatment time (URR) and ultrafiltration volume (URR). The adjusted HR (95% CI) was 0.98 (0.96, 0.99) for URR, 0.51 (0.31, 0.84) for spKt/V and 0.46 (0.30, 0.80) for the eKt/V

Conclusion.

The use of URR leads to larger disagreement with the reference method (eKt/V) treatment target as compared to spKt/V. Low urea distribution volume, short treatment time and low ultrafiltration volumes are predictive parameters for overestimation of dialysis dose when tilizing the alternative methods spKt/V and URR instead of eKt/V. Delivered eKt/V, spKt/V and URR were all positively related to survival.

http://ndt.oxfordjournals.org/content/early/2011/08/04/ndt.gfr396.abstract