The CPH-MBD Cohort Dietary Substudy - Comparison of Methods for Dietary Registrations

The CPH-MBD Cohort - Substudy on Dietary History

The aim of the study is to assess the association between the calcium and phosphorus balance and the stage of kidney disease measured by creatinine clearence in patients with chronic kidney disease stage 4 and 5. The balance is measured a measurement between the recorded diatery intake and the urinary excretion. Additionally a comparison between image based diatery accessment and weighted records will be measured

Study Overview

• Status: Recruiting
• Conditions: CKD; CKD-MBD - Chronic Kidney Disease Mineral and Bone Disorder; Pre-dialysis; Renal Insufficiency Chronic

Detailed Description

All participants will be asked to take photos of all the food and fluids they consume during 24 hours. Additionally participants will be offered to weight their food and fluid for 3 days.

• Study Type: Observational
• Enrollment (Estimated): 50

Contacts and Locations

• Study Contact: Name: Jens Rikardt Andersen, MD, MPA; Phone Number: 004523346654; Email: jra@nexs.ku.dk
• Study Contact Backup: Name: Julian Askøe Bluming, RD; Phone Number: 004591568528; Email: lft190@alumni.ku.dk

Study Locations

• Denmark
  • Herlev, Denmark, 2730
    • Recruiting
    • Herlev Hospital, Dept Nephrology
    • Contact: Julian Askøe Bluming, RD; Phone Number: 004591568528; Email: lft190@alumni.ku.dk
    • Sub-Investigator: Julian A Bluming, RD
  • Capital Region
    • Herlev, Capital Region, Denmark, 2730
      • Active, not recruiting
      • Copenhagen University Hospital - Herlev

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Patients with chronic kidney disease stage 4-5

Description

Inclusion Criteria:

• A glomerular filtration rate of <30 ml ml/min/1.73m2
• 18 years and above

Exclusion Criteria:

None

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Comparison of diatery photograph method with weighted records.	The intake of calcium and phosphate assesed by the 24 hour photos and the 72 hour weighing of food and fluid items will be compared.	3 days
Calcium and phosphate balance in relation to the stage of kidney disease	Measured by the diatery intake of calcium and phosphate in relation to the urinary calcium and phosphate excretion	3 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Urinary Calcium	mmol/day	3 days
Urinary phosphate	mmol/day	3 days
Calcium intake total and the distribution of vegetarian and animal sources	mg/day	3 days
Phosphate intake total and the distribution of vegetarian and animal sources	mg/day	3 days
sodium intake total and the distribution of vegetarian and animal sources	mg/day	3 days
Energy intake	Kcal/day	3 days
Protein intake	g/day	3 days
Fat intake	g/day	3 days
Fluid intake	ml/day	3 days
Plasma phosphate	mmol/l	3 days
Plasma calcium	mmol/l	3 days
Urinary creatinine	mmol/day	3 days
Urinary urea	mmol/day	3 days
Urinary sodium	mmol/day	3 days
Plasma FGF23	mmol/l	3 days
P-calcium P- phosphate product	Can be calculated by multiplying plasma calcium and plasma phosphate	3 days
plasma 25-OH-Vitamin D	nmol/l	3 days
plasma PTH	pmol/l	3 days
Plasma Albumin	g/dl	3 days
eGFR	ml/min/1.73m2	3 days

Collaborators and Investigators

• Sponsor: University of Copenhagen
• Collaborators: Herlev Hospital
• Investigators: Principal Investigator: Jens Rikardt Andersen, MD, MPA, Assoc Prof, University of Copenhagen

Study record dates

Study Major Dates

• Study Start (Actual): December 15, 2025
• Primary Completion (Estimated): May 15, 2026
• Study Completion (Estimated): May 15, 2029

Study Registration Dates

• First Submitted: December 17, 2025
• First Submitted That Met QC Criteria: December 17, 2025
• First Posted (Actual): December 31, 2025

Study Record Updates

• Last Update Posted (Actual): December 31, 2025
• Last Update Submitted That Met QC Criteria: December 17, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Elderly; Humans; Observational; Cohort; Diet; Mineral bone disorder; Phosphate/urine; Calcium/urine; Calcium Balance; Phosphate Balance
• Additional Relevant MeSH Terms: Urogenital Diseases; Endocrine System Diseases; Bone Diseases; Musculoskeletal Diseases; Pathologic Processes; Nutrition Disorders; Male Urogenital Diseases; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Chronic Disease; Disease Attributes; Metabolic Diseases; Renal Insufficiency; Bone Diseases, Metabolic; Parathyroid Diseases; Avitaminosis; Deficiency Diseases; Malnutrition; Rickets; Calcium Metabolism Disorders; Vitamin D Deficiency; Hyperparathyroidism, Secondary; Hyperparathyroidism; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Renal Insufficiency, Chronic; Chronic Kidney Disease-Mineral and Bone Disorder
• Other Study ID Numbers: H-25039131

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Currently no plans for sharing

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No