The effect of online hemodiafiltration on infections: Results from the CONvective TRAnsport STudy

Background: Hemodialysis (HD) patients have a high risk of infections. The uremic milieu has a negative impact on several immune responses. Online hemodiafiltration (HDF) may reduce the risk of infections by ameliorating the uremic milieu through enhanced clearance of middle molecules. Since there are few data on infectious outcomes in HDF, we compared the effects of HDF with low-flux HD on the incidence and type of infections. Patients and Methods: We used data of the 714 HD patients (age 64 ±14, 62% men, 25% Diabetes Mellitus, 7% catheters) participating in the CONvective TRAnsport STudy (CONTRAST), a randomized controlled trial evaluating the effect of HDF as compared to low-flux HD. The events were adjudicated by an independent event committee. The risk of infectious events was compared with Cox regression for repeated events and Cox proportional hazard models. The distributions of types of infection were compared between the groups. Results: Thirty one percent of the patients suffered from one or more infections leading to hospitalization during the study (median follow-up 1.96 years). The risk for infections during the entire follow-up did not differ significantly between treatment arms (HDF 198 and HD 169 infections in 800 and 798 person-years respectively, hazard ratio HDF vs. HD 1.09 (0.88-1.34), P = 0.42. No difference was found in the occurrence of the first infectious event (either fatal, nonfatal or type specific). Of all infections, respiratory infections (25% in HDF, 28% in HD) were most common, followed by skin/musculoskeletal infections (21% in HDF, 13% in HD). Conclusions: HDF as compared to HD did not result in a reduced risk of infections, larger studies are needed to confirm our findings. Trial Registration: ClinicalTrials.gov NCT00205556

Optimization of the convection volume in online post-dilution haemodiafiltration : practical and technical issues

In post-dilution online haemodiafiltration (ol-HDF), a relationship has been demonstrated between the magnitude of the convection volume and survival. However, to achieve high convection volumes (>22 L per session) detailed notion of its determining factors is highly desirable. This manuscript summarizes practical problems and pitfalls that were encountered during the quest for high convection volumes. Specifically, it addresses issues such as type of vascular access, needles, blood flow rate, recirculation, filtration fraction, anticoagulation and dialysers. Finally, five of the main HDF systems in Europe are briefly described as far as HDF prescription and optimization of the convection volume is concerned

Optimization of the convection volume in online post-dilution haemodiafiltration : practical and technical issues

In post-dilution online haemodiafiltration (ol-HDF), a relationship has been demonstrated between the magnitude of the convection volume and survival. However, to achieve high convection volumes (>22 L per session) detailed notion of its determining factors is highly desirable. This manuscript summarizes practical problems and pitfalls that were encountered during the quest for high convection volumes. Specifically, it addresses issues such as type of vascular access, needles, blood flow rate, recirculation, filtration fraction, anticoagulation and dialysers. Finally, five of the main HDF systems in Europe are briefly described as far as HDF prescription and optimization of the convection volume is concerned

Should we still focus that much on cardiovascular mortality in end stage renal disease patients? The CONvective TRAnsport STudy

Contains fulltext : 117652.pdf (publisher's version ) (Open Access)BACKGROUND: We studied the distribution of causes of death in the CONTRAST cohort and compared the proportion of cardiovascular deaths with other populations to answer the question whether cardiovascular mortality is still the principal cause of death in end stage renal disease. In addition, we compared patients who died from the three most common death causes. Finally, we aimed to study factors related to dialysis withdrawal. METHODS: We used data from CONTRAST, a randomized controlled trial in 714 chronic hemodialysis patients comparing the effects of online hemodiafiltration versus low-flux hemodialysis. Causes of death were adjudicated. The distribution of causes of death was compared to that of the Dutch dialysis registry and of the Dutch general population. RESULTS: In CONTRAST, 231 patients died on treatment. 32% died from cardiovascular disease, 22% due to infection and 23% because of dialysis withdrawal. These proportions were similar to those in the Dutch dialysis registry and the proportional cardiovascular mortality was similar to that of the Dutch general population. cardiovascular death was more common in patients <60 years. Patients who withdrew were older, had more co-morbidity and a lower mental quality of life at baseline. Patients who withdrew had much co-morbidity. 46% died within 5 days after the last dialysis session. CONCLUSIONS: Although the absolute risk of death is much higher, the proportion of cardiovascular deaths in a prevalent end stage renal disease population is similar to that of the general population. In older hemodialysis patients cardiovascular and non-cardiovascular death risk are equally important. Particularly the registration of dialysis withdrawal deserves attention. These findings may be partly limited to the Dutch population

A composite score of protein-energy nutritional status predicts mortality in haemodialysis patients no better than its individual components

Item does not contain fulltextBACKGROUND: Protein-energy wasting is tightly associated with mortality in haemodialysis patients. An expert panel of the International Society of Renal Nutrition and Metabolism (ISRNM) has published a consensus on the parameters that define protein-energy nutritional status and posed the question, 'which scoring system most effectively predicts outcome?' The aim of our study was therefore to develop a composite score of protein-energy nutritional status (cPENS) and to assess its prediction of all-cause mortality. METHODS: We used the data of 560 haemodialysis patients participating in the CONvective TRAnsport STudy (CONTRAST). All participants were followed for occurrence of death. Internationally recommended nutritional targets were used as components of the cPENS, including the subjective global assessment (target score >/= 6), albumin (>/= 4.0 g/dL), normalized protein nitrogen appearance (>/= 0.8 g/kg/day), cholesterol (>/= 100 mg/dL), creatinine (>/= 10 mg/dL) and BMI (> 23 kg/m(2)). A Cox regression model was used to analyse the relation between different cPENS variants and mortality. RESULTS: The median follow-up time was 1.4 years (max 4.2). One hundred and five patients (19%) died. A cPENS variant based on albumin, BMI, creatinine and the nPNA yielded the strongest relation with mortality (hazard ratio 0.63, 95% confidence interval 0.54-0.74, P < 0.001), after adjustments for confounders. Some of the individual parameters of the cPENS, notably albumin and creatinine, were related to mortality with similar strength and magnitude. CONCLUSIONS: In conclusion, albumin reflects mortality risk similarly to multiple nutritional parameters combined. This questions the clinical value of the proposed diagnostic criteria for protein-energy wasting

Short-term effects of online hemodiafiltration on phosphate control: a result from the randomized controlled Convective Transport Study (CONTRAST).

Contains fulltext : 89240.pdf (publisher's version ) (Closed access)BACKGROUND: Hyperphosphatemia is an independent risk factor for all-cause and cardiovascular mortality in hemodialysis (HD) patients. Phosphate control often is unsuccessful using conventional dialysis therapies. STUDY DESIGN: Short-term analysis of a secondary outcome of an ongoing randomized controlled trial. SETTING & PARTICIPANTS: 493 (84%) consecutive patients from 589 patients included in the Convective Transport Study (CONTRAST) by January 2009 from 26 centers in 3 countries. INTERVENTION: Online hemodiafiltration (HDF) versus continuation of low-flux HD. OUTCOMES: Differences in change from baseline to 6 months in phosphate levels and proportion of patients reaching phosphate treatment targets (phosphate < or = 5.5 mg/dL). MEASUREMENTS: Phosphate, use of phosphate-binding agents, and proportion of patients achieving treatment targets at baseline, 3 months, and 6 months. RESULTS: Phosphate levels decreased from 5.18 +/- 0.10 (SE) mg/dL at baseline to 4.87 +/- 0.10 mg/dL at 6 months in HDF patients (P < 0.001) and were stable in HD patients (5.10 +/- 0.10 mg/dL at baseline and 5.03 +/- 0.10 mg/dL after 6 months; P = 0.5). The difference in change in phosphate levels between HD and HDF patients (B = -0.24; 95% CI, -0.52 to 0.03; P = 0.08) increased after adjustment for phosphate-binder use (B = -0.36; 95% CI, -0.65 to -0.06; P = 0.02). The proportion of patients reaching phosphate treatment targets increased from 64% to 74% in HDF patients and was stable in HD patients (66% and 66%); the difference between groups reached statistical significance (P = 0.04). Nutritional parameters and residual renal function were similar in both treatment groups. LIMITATIONS: Only predialysis serum phosphate levels were measured; phosphate clearance could therefore not be calculated. CONCLUSION: HDF may help improve phosphate control. Whether this contributes to improved clinical outcome remains to be established.1 januari 201

Role of Residual Renal Function in Phosphate Control and Anemia Management in Chronic Hemodialysis Patients

Item does not contain fulltextBACKGROUND AND OBJECTIVES: There is increasing awareness that residual renal function (RRF) has beneficial effects in hemodialysis (HD) patients. The aim of this study was to investigate the role of RRF, expressed as GFR, in phosphate and anemia management in chronic HD patients. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Baseline data of 552 consecutive patients from the Convective Transport Study (CONTRAST) were analyzed. Patients with a urinary output>/=100 ml/24 h (n=295) were categorized in tertiles on the basis of degree of GFR and compared with anuric patients (i.e., urinary output4.13 ml/min per 1.73 m2), as compared with 46% in anuric patients despite lower prescription of phosphate-binding agents. Mean hemoglobin levels were 11.9+/-1.2 g/dl with no differences between the GFR categories. The ESA index was 31% lower in patients in the upper tertile as compared with anuric patients. After adjustments for patient characteristics, patients in the upper tertile had significantly lower serum phosphate levels and ESA index as compared with anuric patients. CONCLUSIONS: This study suggests a strong relation between RRF and improved phosphate and anemia control in HD patients. Efforts to preserve RRF in HD patients could improve outcomes and should be encouraged