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The effect of high-flux hemodialysis membranes on patient survival has not been unequivocally determined. In this prospective, randomized clinical trial, we enrolled 738 incident hemodialysis patients, stratified them by serum albumin < or = 4 and >4 g/dl, and assigned them to either low-flux or high-flux membranes. We followed patients for 3 to 7.5 yr. Kaplan-Meier survival analysis showed no significant difference between high-flux and low-flux membranes, and a Cox proportional hazards model concurred. Patients with serum albumin < or = 4 g/dl had significantly higher survival rates in the high-flux group compared with the low-flux group (P = 0.032). In addition, a secondary analysis revealed that high-flux membranes may significantly improve survival of patients with diabetes. Among those with serum albumin < or = 4 g/dl, slightly different effects among patients with and without diabetes suggested a potential interaction between diabetes status and low serum albumin in the reduction of risk conferred by high-flux membranes. In summary, we did not detect a significant survival benefit with either high-flux or low-flux membranes in the population overall, but the use of high-flux membranes conferred a significant survival benefit among patients with serum albumin < or = 4 g/dl. The apparent survival benefit among patients who have diabetes and are treated with high-flux membranes requires confirmation given the post hoc nature of our analysis.

Background: Geographical differences in disease prevalence and mortality have been described in the general population and in chronic kidney disease patients in Europe. In this secondary analysis of the Membrane Permeability Outcome (MPO) study, we addressed differences in patient and treatment patterns, and whether these affect patient outcomes. Methods: Participating countries were grouped according to geographical location; thus study centers in France, Greece, Italy, Portugal and Spain were allocated to southern Europe (n=499), and those in all other countries (Belgium, Germany, Poland and Sweden) to northern Europe (n=148). Descriptive analysis of patient and treatment patterns at study start, as well as survival analysis, was performed. Results: In patients from the northern European countries, a higher prevalence of diabetes mellitus and of cardiovascular disease was observed than in those from southern Europe (diabetes 35.1% vs. 21.0%, p=0.0007; cardiovascular disease 40.5% vs. 22.8%, p

STUDY AIMS: To survey bone mineral disturbances in the hemodialysis (HD) population in Europe and current clinical practice in Europe for the prevention, diagnosis and treatment of secondary hyperparathyroidism (SHPT) in HD patients. PRIMARY OBJECTIVES: First, to estimate the prevalence of Kidney Disease Outcomes Quality Initiative (K/DOQI) guideline achievement in a representative sample of European hemodialysis subjects. As part of this objective, we will investigate the prevalence of achievement by type of dialysis, type of center and time on dialysis (less than or greater than 1 year). Among new dialysis subjects (less than 1 year), we will evaluate prevalence of K/DOQI target achievement until the end of the study. The study will run for 3 years. Second, to estimate the association of bone mineral markers (parathyroid hormone [PTH], calcium [Ca], serum phosphorus [P] and calcium phosphate product [CaxP]) classified by achievement of K/DOQI targets with mortality and overall cardiovascular hospitalization. Third, to characterize the longitudinal changes in bone mineral markers. As part of this objective, we will describe the patterns and predictors of bone mineral markers and achievement, with K/DOQI targets, using repeated measurements on individuals over time. SECONDARY OBJECTIVES: First, To estimate the association of bone mineral markers (PTH, Ca, P and CaxP) classified by achievement of K/DOQI targets with specific cardiovascular outcomes, parathyroidectomy, manifest bone disease (including incidence of symptomatic bone fractures), hospitalizations and vascular access. Second, to evaluate the additional value of albumin and hemoglobin levels in conjunction with bone mineral markers in the prediction of mortality and clinical events.

Purpose: Dynamic Contrast Enhanced MRI is a promising non-invasive method for imaging renal perfusion and function [1-5]. The feasibility of voxel-by-voxel perfusion mapping based on deconvolved T1-DCE renal data has already been shown by our group [5]. This study compares the values of perfusion with this method between three different age groups. Methods: Measurements were performed in the supine position at 1.5 T on 15 humans without known or suspected renal disease. The three different age groups were: 20 to 35 years (group A, 5 patients), 50 to 60 years (group B, 6 patients) and above 70 years (group C, 4 patients). Average age was 28 years (SD 7) , 53 years (SD 3) and 72 years (SD 1) respectively in group A, B and C. All experiments were approved by the local ethical board. The first pass of 10 ml Gd-DTPA, injected by power injector at 2cc/s, was acquired using single slice axial IR-prepared Flash (FA 50 °, TI 172 ms, TR 4.4 ms, TE 2.2 ms, slice thickness of 4 mm, matrix size of 128*256, temporal resolution 0.3s/slice ). Postprocessing was performed offline on a personal computer using software written in-house in IDL for Linux (Research Systems, Boulder, CO). Signals were calibrated by using a test tube containing 2mM Gadolinium in saline solution placed in the FOV during the measurement. Signals were converted to tracer concentratios and an arterial input function (AIF) was selected manually in the aorta. The tissue time courses were deconvolved using standard-form Tikhonov regularization and the L-curve criterion for selection of the regularisation parameter [6]. A simple inflow correction was applied. Parametric maps of renal blood flow (RBF), renal blood volume (RBV) and mean transit time (MTT) were calculated as the maximum of the impulse response function (IRF) , the time integral of the IRF and the ratio RBV/ RBF. Only the vascular part of the data (manual cut of at the start of the plateau following the vascular peak in the tracer time courses) was used for calculation in order to estimate RBV.Whole cortical measures of RBF, RBV and MTT were calculated of whole left and right cortex ROIs, drawn on the RBF images. Results: Parametric images with sufficient contrast to noise were obtained in all patients. Figure 1 illustrates a typical result for the quantitative parametric maps of RBF in a patient from each age group. The average results of RBF, RBV and MTT for the different age groups are given in figure 2. Average RBF was 2.1 ml/min/ml with SD 0.5 ml/min/ml (group A), 1.3 ml/min/ml with SD 0.5 ml/min/ml (group B) and 1.5 ml/min/ml with SD 0.7 ml/min/ml (group C). Average RBV and MTT were 0.3 ml/ml SD 0.1 ml/ml and 9s SD 3s (A), 0.3 ml/ml SD 0.2 ml/ml and 11s SD 2 s (B) and 0.3 ml/ml SD 0.06 ml/ml and 13 s SD 4s (C). Based on non parametric statistics (Mann-Whitney), the difference in RBF of age group A and B (p=0.004) and A and C (p=0.03) is significant, while RBF of group B and C (p=0.7) is not significantly different. When we compare RBV, we found no difference between group A and B (p=0.7), group A and C (p=0.6) and B and C (p=1), respectively. For MTT, the results indicate a significant difference between group A and B (p=0.02) and A and C (p=0.004),respectively and no significant difference between group B and C (p=0.8). Conclusion: RBF values are lower than those found in the literature [2,3,8]. This is presumably due to dispersion and/or remaining inflow effects on the AIF estimate: flow related enhancement causes an overestimation of the arterial input function and therefore an underestimation of the perfusion values [9]. The results in these preliminary data suggest a significant difference between RBF and MTT in young patients compared to patients of >50 years, which seems in agreement with physiological considerations since especially in the age group of over 50, more sclerotic glomeruli are found in the healthy population [10]. Although preliminary and highly speculative, study of such physiological mechanisms of pathology with this patient friendly technique seems interesting. References: [1] Hermoye L. et al (2004) MRM 51: 1017- 1025 [2] Schoenberg S. et al (2003) MRM 49:288-298 [3] Aumann S. et al (2003), MRM 49: 276- 287 [4] Pedersen M. et al (2004) Proc. ISMRM 11:879 [5] Dujardin M. et al (2005) MRM 54(4):841-9 [6] Sourbron S. et al (2004) PMB 49:3307-3324 [8] Hierholzer K (1999) Physiologie des Menschen:737-776 [9] Ivancevic M. et al (2003) Proc. ISMRM 11:149 [10]Kaplan C. et al (1975) Am J. Pathol 80(2): 227-34

The cell-mediated immunity was studied in 14 hemodialysis patients by determination of the serum levels of soluble interleukin 2 receptor (sIL-2R) before (hemoglobin 7.9 +/- 0.6 g/dl) and after 16 months of recombinant human erythropoietin (rHuEPO) administration (hemoglobin 10.3 +/- 1.1 g/dl) and compared with 14 hemodialysis patients not receiving the drug (hemoglobin 9.7 +/- 1.4 g/dl). The sIL-2R level was higher in severely anemic patients starting rHuEPO than in patients not receiving the drug (9,414 +/- 2,822 vs. 5,001 +/- 2,905 pg/ml; p < 0.05). At the end of the 16-month observation period, a decrease in sIL-2R of about 48% was observed following raising hemoglobin with rHuEPO, whereas untreated patients exhibited a further increase in sIL-2R, amounting to 59% (p < 0.001). There was a correlation between sIL-2R and hemoglobin (r = -0.40; p < 0.02) at the start of the study and between sIL-2R and hemoglobin (r = -0.43; p < 0.02) and monocyte number (r = 0.48; p < 0.01) at the end of the observation period. Elevated serum sIL-2R levels, a characteristic finding of the altered cell-mediated immunity of hemodialysis patients, may be influenced by the increase in hemoglobin concentration following rHuEPO administration rather than by the hormone itself.