Background. While cardiovascular events remain the primary form of mortality in haemodialysis (HD) patients, few centres are aware of the impact of the hydration status (HS). The aim of this study was to investigate how the magnitude of the prevailing overhydration influences long-term survival.Methods. We measured the hydration status in 269 prevalent HD patients (28% diabetics, dialysis vintage = 41.2 ± 70 months) in three European centres with a body composition monitor (BCM) that enables quantitative assessment of hydration status and body composition. The survival of these patients was ascertained after a follow-up period of 3.5 years. The cut off threshold for the definition of hyperhydration was set to 15% relative to the extracellular water (ECW), which represents an excess of ECW of ∼2.5 l. Cox-proportional hazard models were used to compare survival according to the baseline hydration status for a set of demographic data, comorbid conditions and other predictors.Results. The median hydration state (HS) before the HD treatment (ΔHSpre) for all patients was 8.6 ± 8.9%. The unadjusted gross annual mortality of all patients was 8.5%. The hyperhydrated subgroup (n = 58) presented ΔHSpre = 19.9 ± 5.3% and a gross mortality of 14.7%. The Cox adjusted hazard ratios (HRs) revealed that age (HRage = 1.05, 1/year; P < 0.001), systolic blood pressure (BPsys) (HRBPsys = 0.986 1/mmHg; P = 0.014), diabetes (HRDia = 2.766; P < 0.001), peripheral vascular disease (PVD) (HRPVD = 1.68; P = 0.045) and relative hydration status (ΔHSpre) (HRΔHSpre = 2.102 P = 0.003) were the only significant predictors of mortality in our patient population.Conclusion. The results of our study indicate that the hydration state is an important and independent predictor of mortality in chronic HD patients secondary only to the presence of diabetes. We believe that it is essential to measure the hydration status objectively and quantitatively in order to obtain a more clearly defined assessment of the prognosis of haemodialysis patients.

Longer treatment time (TT) and slower ultrafiltration rate (UFR) are considered advantageous for hemodialysis (HD) patients. The study included 22,000 HD patients from seven countries in the Dialysis Outcomes and Practice Patterns Study (DOPPS). Logistic regression was used to study predictors of TT > 240 min and UFR > 10 ml/h/kg bodyweight. Cox regression was used for survival analyses. Statistical adjustments were made for patient demographics, comorbidities, dose of dialysis (Kt/V), and body size. Europe and Japan had significantly longer (P < 0.0001) average TT than the US (232 and 244 min vs 211 in DOPPS I; 235 and 240 min vs 221 in DOPPS II). Kt/V increased concomitantly with TT in all three regions with the largest absolute difference observed in Japan. TT > 240 min was independently associated with significantly lower relative risk (RR) of mortality (RR = 0.81; P = 0.0005). Every 30 min longer on HD was associated with a 7% lower RR of mortality (RR = 0.93; P < 0.0001). The RR reduction with longer TT was greatest in Japan. A synergistic interaction occurred between Kt/V and TT (P = 0.007) toward mortality reduction. UFR > 10 ml/h/kg was associated with higher odds of intradialytic hypotension (odds ratio = 1.30; P = 0.045) and a higher risk of mortality (RR = 1.09; P = 0.02). Longer TT and higher Kt/V were independently as well as synergistically associated with lower mortality. Rapid UFR during HD was also associated with higher mortality risk. These results warrant a randomized clinical trial of longer dialysis sessions in thrice-weekly HD.

Using data from the international Dialysis Outcomes and Practice Patterns Study (DOPPS), we determined incidence, prevalence, and outcomes among hemodialysis patients with atrial fibrillation. Cox proportional hazards models, to identify associations with newly diagnosed atrial fibrillation and clinical outcomes, were stratified by country and study phase and adjusted for descriptive characteristics and comorbidities. Of 17,513 randomly sampled patients, 2188 had preexisting atrial fibrillation, with wide variation in prevalence across countries. Advanced age, non-black race, higher facility mean dialysate calcium, prosthetic heart valves, and valvular heart disease were associated with higher risk of new atrial fibrillation. Atrial fibrillation at study enrollment was positively associated with all-cause mortality and stroke. The CHADS2 score identified approximately equal-size groups of hemodialysis patients with atrial fibrillation with low (less than 2) and higher risk (more than 4) for subsequent strokes on a per 100 patient-year basis. Among patients with atrial fibrillation, warfarin use was associated with a significantly higher stroke risk, particularly in those over 75 years of age. Our study shows that atrial fibrillation is common and associated with elevated risk of adverse clinical outcomes, and this risk is even higher among elderly patients prescribed warfarin. The effectiveness and safety of warfarin in hemodialysis patients require additional investigation.

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 Յ4 and Ͼ4 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 Յ4 g/dl had significantly higher survival rates in the high-flux group compared with the low-flux group (P ϭ 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 Յ4 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 Յ4 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. 20: 645-654, 200920: 645-654, . doi: 10.1681 Patients who have stage 5 chronic kidney disease (CKD) and are on dialysis therapy have a high mortality rate, estimated between 14 and 26% in Europe and at 24% per year in the United States. 1 The accumulation of various retention solutes over a broad range of molecular weights and chemical composition is involved in the complex pathophysiology of uremia and, among other factors, implicated in the high mortality observed in CKD. 2 Because of their higher porosity, high-flux hemodialysis (HD) membranes have the capacity to remove retention solutes of higher molecular weight than do low-flux membranes, 3 which contain smaller pores. Whether this enhanced solute elimination of high-flux membranes translates J Am Soc Nephrol

Our study illustrated the wide variability in BPsys regardless of the degree of DeltaHS. The HRP provides an invaluable tool for classifying patients in terms of BPsys and DeltaHS and the proximity of these parameters to reference ranges. This represents an important step towards more objective choice of strategies for the optimal treatment of hypertension and FO. Further studies are required to assess the prognostic and therapeutic role of the HRP.