Dietary Phosphorus Load and Postprandial Serum Phosphate in HD Patients

NCT ID: NCT04845724

Last Updated: 2021-04-30

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 8 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2016-11-26
• Study Completion Date: 2016-12-14

Brief Summary

This study is to investigate the acute postprandial effect of a modified versus standard low phosphorus diet on serum phosphate, potassium and intact parathyroid levels in prevalent hemodialysis (HD) patients

Detailed Description

Background: Potential dietary strategies for controlling hyperphosphataemia include the use of protein sources with lower phosphorus bioavailability such as pulses and nuts, focus on phosphorus to protein ratios and the avoidance of all phosphate additives.

Method: Controlled crossover feeding study in 8 HD patients. On one day, participants were directly observed eating a standard low phosphorous diet and on the other day, a modified low phosphorus diet. The modified diet included beef and less dairy, with a lower phosphorus to protein ratio, as well as plant-based protein, whole grains, pulses and nuts containing phytates which reduces phosphorus bioavailability. Both diets were tailored for each participant to provide 1.1g protein/kg ideal body weight. Participants provided fasting bloods before breakfast, a pre-prandial sample before lunch and samples at one hour intervals for the four hours after the meal, for analysis of phosphate, potassium and intact parathyroid hormone (iPTH).

Conditions

Hemodialysis

Keywords

Dietary phosphorus; Hyperphosphatemia; Hyperkalaemia; Phytate; Hemodialysis

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

Standard Diet

The standard diet was based on the current dialysis diet sheet. The standard diet main meal contained a higher proportion of foods with a higher phosphorus to protein ratio (salmon and dairy), and foods with higher phosphorus bioavailability (cake). The diet was tailored for each participant to provide 1.1g protein/kg ideal body weight. The major differences between the diets were at the main meal.

Group Type: ACTIVE_COMPARATOR

Standard Diet

Intervention Type: OTHER

Modified Diet

The modified diet, representative of the proposed modified phosphorus diet used food of lower phosphorus to protein ratio such as beef and less dairy. Approximately 30% dietary phosphorus in the modified diet came from foods with significant phytate content such as pulses, nuts and whole grains. The modified diet was tailored for each participant to provide 1.1g protein/kg ideal body weight.

Group Type: EXPERIMENTAL

Modified Diet

Intervention Type: OTHER

Interventions

Standard Diet

Intervention Type: OTHER

Modified Diet

Intervention Type: OTHER

Other Intervention Names

Modified Diet

Eligibility Criteria

Inclusion Criteria

• > 18 years of age;
• on dialysis for > 3 months;
• pre-dialysis serum phosphate < 2.5 mmol/L and
• serum potassium < 6.3 mmol/L on most recent routine monthly blood test;
• urinary outputs of < 200 ml/day by self-report;
• being in their usual state of health

Exclusion Criteria

• history of diabetes mellitus
• history of parathyroidectomy
• history of calciphylaxis

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 80 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University College Cork

OTHER

Sponsor Role: lead

Responsible Party

Joseph Eustace

Professor Joseph Eustace

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Joseph Eustace, MB

Role: PRINCIPAL_INVESTIGATOR

University College Cork

References

Byrne F, Gillman B, Palmer B, Kiely M, Eustace J, Kearney P, Davidson F, Shiely F. The effect of dietary phosphorus load and food matrix on postprandial serum phosphate in hemodialysis patients: a pilot study. HRB Open Res. 2021 Nov 10;4:119. doi: 10.12688/hrbopenres.13382.1. eCollection 2021.

Reference Type: DERIVED

PMID: 35187396 (View on PubMed)

Other Identifiers

16-CRFC-32

Identifier Type: -

Identifier Source: org_study_id