Low-Phosphate Diet and Fibroblast Growth Factor-23 Level

NCT ID: NCT03367338

Last Updated: 2018-10-02

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Clinical Phase

NA

Total Enrollment

35 participants

Study Classification

INTERVENTIONAL

Study Start Date

2018-01-03

Study Completion Date

2018-06-08

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

The aims of the study are to evaluate the effect of low-phosphate diet on FGF23 level and to determine the optimal amount of dietary phosphate restriction in hemodialysis patients. In particular, the investigators will assess the comparing effect of pre-specified low-phosphate diets, very low-phosphate diet, phosphate-to-protein ratio (PPR) value of 8 mg/g, versus low-phosphate diet, PPR value of 10 mg/g, on the change of FGF23 and phosphate level.

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

In patients with hemodialysis, the prevalence of cardiovascular disease (CVD) is high, and is the leading cause of death. Among several cardiovascular risk factors of hemodialysis patients, elevated fibroblast growth factor-23 (FGF23) level is common, and plays major role in the development of CVD with independent pathophysiologic mechanisms. Evidence from animal studies demonstrated that low-phosphate diet reduced FGF23 level. Clinical trials assessing the effect of dietary phosphate restriction on FGF23 focused on non-dialysis populution. However, little is known about the effect of low-phosphate diet on FGF23 in hemodialysis patients who have higher prevalence of hyperphosphatemia and severely elevated FGF23 level. In addition, current clinical guideline, based on evidence from observational studies of non-dialysis population, has recommended that dietary phosphate intake should be restricted to 800-1000 mg/day (adjusted for dietary protein needs) when serum phosphate levels are greater than 5.5 mg/dL in those with kidney failure. For hemodialysis population, the optimal amount of dietary phosphate restriction has not been determined. The aims of the study are to evaluate the effect of low-phosphate diet on FGF23 level and to determine the optimal amount of dietary phosphate restriction in hemodialysis patients. In particular, the investigators will compare the effect of pre-specified low-phosphate diets, very low-phosphate diet, phosphate-to-protein ratio (PPR) value of 8 mg/g, versus low-phosphate diet, PPR value of 10 mg/g, on the change of FGF23 and phosphate level.

It is to conduct a randomized, active-controlled trial with cross-over design at a hemodialysis unit of tertiary teaching hospital in Northern Taiwan. Subjects with aged older than 20 years, end-stage renal disease undergoing thrice-weekly hemodialysis for more than three months, having adequate dialysis (urea reduction ratio equal to or greater than 65%) and the most recent serum phosphate level greater than 5.5 mg/dL or between 3.5 and 5.5 mg/dL with regular phosphate binder use will be randomly assigned into two groups: those in group A will receive 2-day diet with known PPR of 8 mg/g, followed by 5-day washout period and then receive another 2-day diet with PPR of 10 mg/g. The opposite order of diets will be prescribed in group B. The study diets will be prepared and cooked at hospital cafeteria. Dietary compositions of the study diets were analyzed before the start of the study. Primary outcome measures are difference in change-from-baseline intact FGF-23 level between the two dietary interventions. Secondary outcomes include changes in serum phosphate, intact parathyroid hormone and C-terminal FGF-23 level.

Since food additives include readily absorbable inorganic phosphorus, only natural food sources were chosen for study diets. All study food items had the following unique characteristics including: 1. Using locally produced raw materials. 2. Meeting healthy and safety requirements. 3. Complying with national quality standards. Prior to enrollment of the eligible patients, the study diets were prepared and cooked with the food hygiene practice using Hazard Analysis and Critical Control Points (HACCP) system at hospital cafeteria and dietary composition of study diets were analyzed for chemical analysis. With reference to Association of Official Analytical Communities (AOAC) Official Method 984.27, phosphorus, and calcium were determined by inductively coupled plasma-optical emission spectrometer (ICP-OES) analysis with the detection limit of 0.1 mg/L. In brief, the sample weight were obtained, the edible portions of samples were ashed at high temperature, digested in nitric acid, and used inductively coupled plasma to determine their actual contents of phosphorus and calcium. With reference to Taiwanese official methods, study diets were measured for analyses of protein, fat, saturated fat, sugar, moisture, and ash. Carbohydrates were calculated by the formula: 100 - (Protein + Fat + Moisture + Ash) (g/100 g). Calories were calculated by the formula: Protein (g) x 4 kcal + Fat (g) x 9 kcal + Carbohydrate (g) x 4 kcal.

Based on the measured values of food items, dietitian had crafted low-phosphate diets. Less than 800 mg per day of phosphate amount is designed to fulfill the current clinical recommendation. Two different contents of phosphate diets were prepared to find out the optimal amount of dietary phosphate. Each of the diets was designed to have similar calcium, protein and total caloric contents but only differ in phosphate contents. To enhance nutrition, and to reduce phosphate amount and bioavailability, study diets were designed to fulfill the following criteria including high protein diet (≧1.2 g/kg/day), adequate calories (≧ 30 kcal/kg/day), low phosphate-to-protein ratio (\< 10 mg/g), and higher percentage of plant source of phosphate than that of animal source. In addition, meats were sliced and boiled for 30 minutes before cooking to reduce the amount of phosphate while preserving protein content.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Chronic Kidney Disease Requiring Chronic Dialysis Hyperphosphatemia Dietary Intervention Elevated Fibroblast Growth Factor-23

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

RANDOMIZED

Intervention Model

CROSSOVER

Primary Study Purpose

TREATMENT

Blinding Strategy

TRIPLE

Participants Caregivers Outcome Assessors

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

Group A

Participants in group A consumed a 2-day very low-phosphate diet with PPR of 8 mg/g, followed by a 5-day washout period in which they adhered to usual diets, and then consumed a 2-day low-phosphate diet with PPR of 10 mg/g.

Group Type ACTIVE_COMPARATOR

Low-phosphate diet

Intervention Type OTHER

Very low-phosphate diet, PPR value of 8 mg/g, vs. low-phosphate diet, PPR value of 10 mg/g

Group B

Compared with group A, the opposite order of low-phosphate diets will be prescribed in group B.

Group Type ACTIVE_COMPARATOR

Low-phosphate diet

Intervention Type OTHER

Very low-phosphate diet, PPR value of 8 mg/g, vs. low-phosphate diet, PPR value of 10 mg/g

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

Low-phosphate diet

Very low-phosphate diet, PPR value of 8 mg/g, vs. low-phosphate diet, PPR value of 10 mg/g

Intervention Type OTHER

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* Subjects with end-stage kidney disease undergoing thrice-weekly hemodialysis for more than three months, the most recent serum phosphate level greater than 5.5 mg/dL or between 3.5 and 5.5 mg/dL with regular phosphate binder use, and having adequate dialysis (urea reduction ratio equal to or greater than 65%)

Exclusion Criteria

* Subjects with serum albumin less than 2.5 g/dL, having psychiatric disorders, mental retardation or poor adherence
Minimum Eligible Age

20 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

Wan-Chuan Tsai

OTHER

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Wan-Chuan Tsai

Attending Physician

Responsibility Role SPONSOR_INVESTIGATOR

Principal Investigators

Learn about the lead researchers overseeing the trial and their institutional affiliations.

Wan-Chuan Tsai

Role: PRINCIPAL_INVESTIGATOR

Far Eastern Memorial Hospital

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

Far Eastern Memorial Hospital

New Taipei City, , Taiwan

Site Status

Countries

Review the countries where the study has at least one active or historical site.

Taiwan

References

Explore related publications, articles, or registry entries linked to this study.

Grabner A, Amaral AP, Schramm K, Singh S, Sloan A, Yanucil C, Li J, Shehadeh LA, Hare JM, David V, Martin A, Fornoni A, Di Marco GS, Kentrup D, Reuter S, Mayer AB, Pavenstadt H, Stypmann J, Kuhn C, Hille S, Frey N, Leifheit-Nestler M, Richter B, Haffner D, Abraham R, Bange J, Sperl B, Ullrich A, Brand M, Wolf M, Faul C. Activation of Cardiac Fibroblast Growth Factor Receptor 4 Causes Left Ventricular Hypertrophy. Cell Metab. 2015 Dec 1;22(6):1020-32. doi: 10.1016/j.cmet.2015.09.002. Epub 2015 Oct 1.

Reference Type BACKGROUND
PMID: 26437603 (View on PubMed)

Isakova T, Gutierrez OM, Smith K, Epstein M, Keating LK, Juppner H, Wolf M. Pilot study of dietary phosphorus restriction and phosphorus binders to target fibroblast growth factor 23 in patients with chronic kidney disease. Nephrol Dial Transplant. 2011 Feb;26(2):584-91. doi: 10.1093/ndt/gfq419. Epub 2010 Jul 14.

Reference Type BACKGROUND
PMID: 20631407 (View on PubMed)

Di Iorio B, Di Micco L, Torraca S, Sirico ML, Russo L, Pota A, Mirenghi F, Russo D. Acute effects of very-low-protein diet on FGF23 levels: a randomized study. Clin J Am Soc Nephrol. 2012 Apr;7(4):581-7. doi: 10.2215/CJN.07640711. Epub 2012 Feb 23.

Reference Type BACKGROUND
PMID: 22362063 (View on PubMed)

Tsai WC, Wu HY, Peng YS, Hsu SP, Chiu YL, Chen HY, Yang JY, Ko MJ, Pai MF, Tu YK, Hung KY, Chien KL. Effects of lower versus higher phosphate diets on fibroblast growth factor-23 levels in patients with chronic kidney disease: a systematic review and meta-analysis. Nephrol Dial Transplant. 2018 Nov 1;33(11):1977-1983. doi: 10.1093/ndt/gfy005.

Reference Type BACKGROUND
PMID: 29420827 (View on PubMed)

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

FEMH-IRB-106108-F

Identifier Type: -

Identifier Source: org_study_id

More Related Trials

Additional clinical trials that may be relevant based on similarity analysis.