The Effect of On-line Hemodiafiltratrion on Nutritional Status and Body Composition

Study Overview
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Brief Summary
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Compared to conventional hemodialysis (HD), on-line hemodiafiltration (OL-HDF) achieves a more efficient removal of uremic toxins and reduces inflammation, which could favourably affect nutritional status. The aim of this study was to evaluate the 1-year effect of OL-HDF on nutritional status and body composition in prevalent HD patients.

Detailed Description
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Postdilution on-line hemodiafiltration (OL-HDF) is considered the most efficient renal replacement treatment modality. Compared with conventional hemodialysis (HD), OL-HDF enables a better removal of middle molecular weight uremic toxins by combining convective and diffusive clearance. Although higher convection volume exchange has been associated with an increased survival advantage for dialysis patients, the mechanisms by which OL-HDF may improve outcomes remain unknown. On the basis of improved toxin removal, a potential benefit of OL-HDF on nutritional status has been postulated. However, evidence on the effect of OL-HDF on nutritional status is scarce and at times conflicting. Some observational and interventional studies have suggested that OL-HDF is associated with improved nutritional parameters; others have found no effect; and one study even reported negative effects of OL-HDF on nutritional status. The majority of these observations come from cohort studies, non-controlled interventions and/or secondary analysis of controlled trials. Further, there are currently no data examining the plausible effect of postdilution OL-HDF on body composition. To clarify this important knowledge gap, this prospective, controlled, study evaluated the effects of high volume postdilution OL-HDF on nutritional status and body composition in prevalent HD patients.

Official Title
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The Effect of On-line Hemodiafiltratrion on Nutritional Status and Body Composition: A Prospective, Controlled, Pilot Study

Conditions
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Chronic Kidney Disease Requiring Chronic Dialysis

Intervention / Treatment
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* Device: High-flux hemodialysis
* Device: On line-hemodiafiltration


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: being over 18 yr old; receiving stable high-flux hemodialysis treatment for at least 3 mo (Kt/Vurea ≥1.2 and hemodialysis performed 3.0 to 6.0 h, three times weekly), and agreed to give informed consent. Exclusion Criteria: malabsorption syndrome; active malignant disease or other critical illnesses; or treated with steroids or antiandrogens.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: High-flux hemodialysis<br>3 times per week | Device: High-flux hemodialysis<br>* Hemodialysis treatment thrice weekly with the high-flux FX-100 dialyzer (Fresenius Medical Care, Bad Homburg, Germany; membrane: Helixone®; surface: 2.2 m2; UF coefficient: 73 ml/h mm Hg; ß2-microglobulin-sieving coefficient: 0.8; albumin-sieving coefficient: 0.001), including a minimum target dialysis dose (Kt/Vurea) ≥1.2 and a session length of 3.0 to 6.0 h. Hemodialysis treatments were performed with the 5008 hemodialysis system (Fresenius Medical Care).<br>|
| Experimental: On line-hemodiafiltration<br>3 times per week | Device: On line-hemodiafiltration<br>* Post-dilution on line-hemodiafiltration treatment thrice weekly with the high-flux FX-100 dialyzer (Fresenius Medical Care, Bad Homburg, Germany; membrane: Helixone®; surface: 2.2 m2; UF coefficient: 73 ml/h mm Hg; ß2-microglobulin-sieving coefficient: 0.8; albumin-sieving coefficient: 0.001), including a minimum target dialysis dose (Kt/Vurea) ≥1.2 and a session length of 3.0 to 6.0 h. Post-dilution on line-hemodiafiltration treatments were performed with the 5008 hemodialysis system (Fresenius Medical Care), with automatic adjustment of the substitution fluid flow rate for maximising substitution volume while simultaneously avoiding haemoconcentration and filter clotting.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Lean tissue mass in kilograms | Change from baseline to end of study in lean tissue mass in kilograms, measured quarterly throughout the 12-month intervention. Lean tissue mass was assessed by multi-frequency bioimpedance spectroscopy (Fresenius Medical Care) by experienced research staff blinded to all clinical and biochemical data of the patients. In order to control for potential variability and the effect of overhydration, all bioimpedance analyses were performed before a mid-week dialysis session. | Baseline, 4, 8, and 12 months. | 
| Intracellular water in liters | Change from baseline to end of study in intracellular water in liters, measured quarterly throughout the 12-month intervention. Intracellular water was assessed by multi-frequency bioimpedance spectroscopy (Fresenius Medical Care) by experienced research staff blinded to all clinical and biochemical data of the patients. In order to control for potential variability and the effect of overhydration, all bioimpedance analyses were performed before a mid-week dialysis session. | Baseline, 4, 8, and 12 months. | 
| Body cell mass in kilograms | Change from baseline to end of study in body cell mass in kilograms, measured quarterly throughout the 12-month intervention. Body cell mass was assessed by multi-frequency bioimpedance spectroscopy (Fresenius Medical Care) by experienced research staff blinded to all clinical and biochemical data of the patients. In order to control for potential variability and the effect of overhydration, all bioimpedance analyses were performed before a mid-week dialysis session. | Baseline, 4, 8, and 12 months. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Serum prealbumin levels in milligrams per deciliter | Change from baseline to end of study in serum prealbumin concentration in milligrams per decilitre, measured quarterly throughout the 12-month intervention. Pre-dialytic blood samples were collected after insertion of the access needle, and the post-dialytic sample was drawn from the arterial needle after slowing the blood punt to 50 ml/min. Prealbumin was determined by nephelometry with the IMMAGE800 Immunochemistry System (Beckman Coulter, Galway, Ireland). | Baseline, 4, 8, and 12 months. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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body composition, bioimpedance, hemodialysis, hemodiafiltration, nutritional status, protein energy wasting