The Effect of a 2-week Preoperative Vegan Diet Versus Omnivorous Diet on the Protein Turnover in the Osteoarthritic Knee
KneeT-vegan
1 other identifier
interventional
40
1 country
2
Brief Summary
Rationale: Protein from plant-based foods may be unable to stimulate protein synthesis due to a suboptimal essential amino acid content and a lower digestibility. However, a more optimal amino acid profile may be achieved by increasing portions sizes and blending multiple plant-based sources. Studies investigating the anabolic properties of vegan diets (total elimination of animal-based foods) rather than single plant-based foods in older adults are scarce. It remains unknown if a vegan diet can also affect protein synthesis rates in other musculoskeletal tissues than muscle. Primary objective: To assess the effects of a 2-week preoperative vegan diet in comparison to an omnivorous diet on protein synthesis rates in Hoffa's fat pad, synovium, tendon, bone, ligaments, menisci, and cartilage in older adults with knee osteoarthritis undergoing total knee arthroplasty. Secondary objective: To assess the effects of a 2-week preoperative vegan diet in comparison to an omnivorous diet on blood pressure and plasma amino acids in older adults with knee osteoarthritis undergoing total knee arthroplasty. Study design: Multi-center, randomized, controlled trial with an intervention and a control group. Study population: 40 older adults (60 - 80 years) with osteoarthritis of the knee undergoing total knee replacement. Intervention: Controlled vegan diet versus controlled omnivorous diet, for a duration of 14 days. Main study parameters/endpoints: Primary study parameters are protein synthesis rates of Hoffa's fat pad, synovium, tendon, bone, ligament, menisci, and cartilage. Secondary parameters include blood pressure and plasma amino acids.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P25-P50 for not_applicable
Started Oct 2024
Typical duration for not_applicable
2 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
November 8, 2023
CompletedFirst Posted
Study publicly available on registry
November 14, 2023
CompletedStudy Start
First participant enrolled
October 22, 2024
CompletedPrimary Completion
Last participant's last visit for primary outcome
December 1, 2026
ExpectedStudy Completion
Last participant's last visit for all outcomes
December 1, 2026
April 1, 2025
March 1, 2025
2.1 years
November 8, 2023
March 25, 2025
Conditions
Outcome Measures
Primary Outcomes (1)
Change in tissue-specific protein synthesis rates
Tissue-specific protein synthesis rates in the knee using D2O dosing methodology
During the 2-week preoperative period
Secondary Outcomes (2)
Change in blood pressure
Measured at baseline and 1 day before surgery
Change in plasma amino acids
During the 2-week preoperative period
Study Arms (2)
Vegan group
EXPERIMENTALSubjects in the vegan group will receive a vegan diet during the 2-week preoperative period.
Omnivorous group
ACTIVE COMPARATORSubjects in the omnivorous group will receive an omnivorous diet during the 2-week preoperative period.
Interventions
Eligibility Criteria
You may qualify if:
- Written informed consent;
- Patients scheduled for total knee arthroplasty;
- BMI between 20-32 kg/m2;
- Aged 60 - 80 years;
- Mentally competent, as judged by the treating physician;
You may not qualify if:
- Following a vegetarian or vegan diet or a diet that affects protein intake during the six months prior to the study;
- Participating in a structured progressive exercise training program in the past three months;
- Lost more than 4 kg body weight during three months prior to the study;
- Chronic use of medications that affect protein metabolism (i.e. systemic corticosteroids, or prescription strength acne medications);
- Being diagnosed with one of the following: diabetes mellitus, rheumatoid arthritis, peripheral artery disease Fontaine III or IV, COPD GOLD III or IV, neoadjuvant chemotherapy or radiotherapy, phenylketonuria, collagen disorders (e.g. Marfan and Ehler-Danlos);
- Alcohol abuse;
- Surgical intervention to the knee in the past four weeks;
- Total parenteral nutrition at day of surgery;
- Glomerular filtration rate (GFR) \<20 mL/min/1.73 m2;
- Allergic or intolerant to any product included in the diets;
- Osteoarthritis of the knee secondary to septic arthritis, osteonecrosis, fracture, osteochondritis dissecans, or malignant processes;
- Any other medical condition that may interfere with the safety of the participants or the outcome parameters, in the investigators judgement;
- Not willing to stop nutritional supplements, with the exception of vitamin D and supplements on medical advice.
- Investigator's uncertainty about the willingness or ability of the participant to comply with the protocol instructions;
- Participation in other studies that may have an impact on the outcomes during the three months before the start of the current study.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Wageningen Universitylead
- Gelderse Vallei Hospitalcollaborator
- Rijnstate Hospitalcollaborator
Study Sites (2)
Rijnstate Hospital
Arnhem, Netherlands
Hospital Gelderse Vallei
Ede, Netherlands
MeSH Terms
Interventions
Intervention Hierarchy (Ancestors)
Study Officials
- PRINCIPAL INVESTIGATOR
Lisette de Groot, PhD
Wageningen University
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- not applicable
- Allocation
- RANDOMIZED
- Masking
- NONE
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
- Responsible Party
- PRINCIPAL INVESTIGATOR
- PI Title
- prof.dr.ir.
Study Record Dates
First Submitted
November 8, 2023
First Posted
November 14, 2023
Study Start
October 22, 2024
Primary Completion (Estimated)
December 1, 2026
Study Completion (Estimated)
December 1, 2026
Last Updated
April 1, 2025
Record last verified: 2025-03
Data Sharing
- IPD Sharing
- Will not share