Hormonal changes induced by changing amounts of protein and phosphorus in the diet of healthy volunteers
| ISRCTN | ISRCTN10876564 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN10876564 |
| Protocol serial number | 2008/155 |
| Sponsor | Vrije University Medical Centre (VUMC) (Netherlands) |
| Funder | Vrije University Medical Centre (VUMC) (Netherlands) - Departments of nephrology and biochemistry |
- Submission date
- 06/05/2010
- Registration date
- 27/05/2010
- Last edited
- 30/08/2011
- Recruitment status
- No longer recruiting
- Overall study status
- Completed
- Condition category
- Urological and Genital Diseases
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data
Record updated in last year
Plain English summary of protocol
Not provided at time of registration
Contact information
Dr Marc Vervloet
Scientific
Scientific
De Boelelaan 1117
Amsterdam
1081 HV
Netherlands
| Phone | 31-20-4442673 |
|---|---|
| m.vervloet@vumc.nl |
Study information
| Primary study design | Interventional |
|---|---|
| Study design | Non-randomised controlled crossover group trial |
| Secondary study design | Non randomised controlled trial |
| Study type | Participant information sheet |
| Scientific title | Effects of changes in dietary phosphorus intake on fibroblast growth factor 23 (FGF23) levels in healthy volunteers: a controlled crossover trial |
| Study objectives | Background: This study is related to patients with kidney disease. Kidney disease, as defined by a decline in estimated Glomerular Filtration Rate (GFR), as even in early stages related to disturbances in the metabolism of minerals, especially calcium and phosphorus, and Fibroblast growth factor 23 (FGF23). The latter is related to clinical endpoints and mortality. Hypothesis Changes in phosphate intake lead to parallel changes in levels of FGF23, even in healthy volunteers. These changes in FGF23 in turn lead to increases in phosphaturia and changes in levels of 1,25 dihydroxyvitamin D, both independent from possible changes in PTH or serum phosphate levels. |
| Ethics approval(s) | The local medical ethics committe (Medisch Ethische Toetsingscommissie) of Vrije University Medical Centre (VUMC) approved on the 11th of August 2008 (ref: 2008/155) |
| Health condition(s) or problem(s) studied | Kidney disease |
| Intervention | Subjects are switched from regular diet to phosphate-restricted diet for two days, and the back to regular diet for ten days. After that they are switched from regular diet to phopsphate-enriched diet and the back again. No other interventions are made. Both the primary and secondary endpoint were determined during the interventional periods, because changes induced by the intervention are almost immediate. |
| Intervention type | Other |
| Primary outcome measure(s) |
Changes in FGF23 levels, determined using sandwich ELISA for both C-terminal FGF23 (provided by Immutopics, San Clemente, USA) and Intact FGF23 (provided by Kainos, Japan). |
| Key secondary outcome measure(s) |
1. Changes in phosphaturia |
| Completion date | 31/12/2008 |
Eligibility
| Participant type(s) | Patient |
|---|---|
| Age group | Adult |
| Sex | All |
| Target sample size at registration | 10 |
| Key inclusion criteria | 1. Male or female 2. Non-smoking subjects 3. Normal renal function, as defined by estimated Glomerular Filtration Rate (GFR) above 80 ml/min. 4. Females should have a negative test for pregnancy at baseline |
| Key exclusion criteria | 1. Abnormal kidney function 2. Substantial comorbidity |
| Date of first enrolment | 01/08/2008 |
| Date of final enrolment | 31/12/2008 |
Locations
Countries of recruitment
- Netherlands
Study participating centre
De Boelelaan 1117
Amsterdam
1081 HV
Netherlands
1081 HV
Netherlands
Results and Publications
| Individual participant data (IPD) Intention to share | No |
|---|---|
| IPD sharing plan summary | Not provided at time of registration |
| IPD sharing plan |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Participant information sheet | Participant information sheet | 11/11/2025 | 11/11/2025 | No | Yes |
