Diet Interventions
Conditions
Keywords
Diet Interventions, rheumatoid arthritis
Brief summary
The main goal of this trial is to investigate whether a dietary intervention based on a typical Mediterranean Diet enriched with fermented foods (MedDiet+) can impact gut microbiota and RA-related outcomes.
Detailed description
100 RA patients will be recruited at ULS Santa Maria in Lisbon, Portugal, and randomly assigned to either the intervention (MedDiet+) or the control group. The 12-week nutritional intervention will include a personalized dietary plan based on the MedDiet+ pattern, educational resources, food basket deliveries, and clinical culinary workshops, all developed and monitored weekly by registered dietitians. The control group will receive general recommendations for a healthy diet at baseline. The intervention's effects will be assessed by evaluating disease activity, functional status, quality of life, intestinal permeability, endotoxemia, inflammatory biomarkers, intestinal and oral microbiota, serum proteomics, and serum glycome profile characterisation.
Interventions
OTHERMedDiet+ intervention
Study arm will consume a Mediterranean like style diet enriched in fermented foods for 12 weeks
Study arm will be given general healthy eating advice at baseline.
Sponsors
Gulbenkian Institute for Molecular Medicine
Lisbon Academic Medical Center - Centro Académico de Medicina de Lisboa
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Masking description
Block randomization was performed through an online software, and patients are being allocated into the intervention (MedDiet+) or control groups. Due to the nature of the trial, the participants and the dietitians responsible for implementing the study are not blinded. However, the clinicians evaluating the clinical outcome measures (disease activity score in 28 joints and the doppler ultrasound score in 32 joints) and the researchers performing the laboratory tests are blinded.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* RA patients (ACR/EULAR2010 criteria) * Age \>18-years * Disease duration \>1-year * Active disease (DAS28 \> 2.6units) * On stable medication for 12 weeks * Low/medium MedDiet adherence (PREDIMED\<10) * Willing to comply with study protocol
Exclusion criteria
* Prednisolone dose ≥ 7.5 mg/day * Antibiotic therapy 4-weeks prior to baseline * Persistent use of NSAID's * Inflammatory or irritable bowel disease * Celiac disease * Chronic diarrhea * Diabetes * Other immune-mediated inflammatory diseases besides RA * Major organ dysfunction * Cancer diagnosed in the last five years * Health conditions which may difficult participation (cognitive impairment/psychiatric disease) * Pregnant or lactating individuals
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| DAS28-ESR | 12 weeks | Disease Activity Score in 28 Joints Calculated with erythrocyte sedimentation rate (DAS28-ESR), higher scores indicate higher disease activity |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| EULAR Good or Moderate Response | 12 weeks | Proportion of patients achieving moderate or good response based on European Alliance of Associations for Rheumatology (EULAR) criteria; measured with Disease Activity Score using Erythrocyte Sedimentation Rate) (DAS28-ESR\<2.6 (%). |
| Ultrasound score | 12 weeks | i. Change in ultrasound score for 32 joints assessed using a 0-3 scale for grey scale and power Doppler, score (0-3) per joint, higher scores indicate worse disease activity. ii. Proportion of patients achieving a 10% improvement in the ultrasound joint score (%). |
| DAS28-CRP | 12 weeks | Change in Disease Activity Score in 28 joints calculated with C-reactive protein (DAS28-CRP), higher scores indicate worse disease activity. |
| Quality of life | 12 weeks | Change in Short Form-36 (SF-36): higher scores indicate better quality of life, score ranging from 0 to 100 |
| Functional status | 12 weeks | Change in Health Assessment Questionnaire (HAQ): higher scores indicate greater disability, score ranging from 0 to 3 |
| α- and β- diversity of the gut and oral microbiota | 12 weeks | i. Change in α-diversity: changes in alpha diversity between the different groups using the Chao-1 index, Phylogenetic Diversity index, Simpson index, and Shannon index. ii. Change in β-diversity: we will perform Principal Coordinates Analysis (PCoA) using Bray-Curtis dissimilarity, Weighted UniFrac, and Unweighted |
| Changes in key gut microbial species | 12 weeks | i. Change in the relative abundance of Lactobacillus/ Limosilactobacillus and Bifidobacterium, relative abundance in percentage. ii. Change in butyrate-producing species, relativ abundance in percentage. iii. Change in H₂S-producing species, relative abundance in percentage. |
| Intestinal permeability | 12 weeks | Change in the lactulose/mannitol ratio |
| Endotoxemia | 12 weeks | Change in Endotoxemia measured by TLR4 activation in reporter cells |
| ESR | 12 weeks | Change in erythrocyte sedimentation rate (ESR, mm/hr) |
| Faecal calprotectin | 12 weeks | Change in faecal calprotectin (μg/g) |
| CD14s | 12 weeks | Change in serum soluble CD14 (CD14s, ng/mL) |
| LBP | 12 weeks | Change in lipopolysaccharide-binding protein (LBP, ng/mL) |
| IFABP | 12 weeks | Change in intestinal fatty acids binding protein levels (IFABP, pg/mL) |
| Lipid Profile | 12 weeks | i.Change in triglycerides (mg/dL) ii.Change in total cholesterol (mg/dL) iii.Change in high-density lipoprotein cholesterol (HDL, mg/dL) iv.Change in low-density lipoprotein cholesterol (LDL, mg/dL) |
| Body composition | 4 th, 8 th and 12 th weeks | Change in body mass index (BMI, kg/m²; weight in kilograms and height in meters will be comined to report BMI in kg/m²) |
| Anthropometric measurements | 4 th, 8 th and 12 th weeks | Change in body mass index and waist circumference |
| Waist circunference | 4 th, 8 th and 12 th weeks | Change in waist circumference (cm) |
| CRP | 12 weeks | Change in C-reactive protein (CRP, mg/L) |
Other
| Measure | Time frame | Description |
|---|---|---|
| zonulin levels, serum proteomics, and serum glycomics | 12 weeks | We will also analyse: i. Change in zonulin levels (ng/mL). ii. Change in serum proteomics. iii. Change in serum glycomics. |
Countries
Portugal
Contacts
Primary ContactCatarina Sousa Guerreiro, PhD
Outcome results
None listed