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Nutrition in Rheumatic Diseases

Not Applicable
Recruiting
Conditions
Rheumatoid Arthritis
Polyarthritis
Spondyloarthritis
Interventions
Dietary Supplement: Placebo (soya)
Dietary Supplement: Omega-3
Behavioral: Dietary guidance
Registration Number
NCT04586933
Lead Sponsor
Haukeland University Hospital
Brief Summary

Background: Patients with inflammatory rheumatic diseases (IRD) are prone to malnutrition for several reasons. The diseases and treatment can cause reduced intake and absorption of nutrients and the inflammatory processes may cause an increased demand for nutrients, especially proteins. Studies report that nutritional status can affect disease activity. Dietary supplement of 3-4 gram omega-3 has shown beneficial effect upon disease activity in patients with IRD.

Aim: To investigate whether improved dietary intake with and without supplements of omega-3 will affect disease activity in patients with rheumatoid arthritis (RA) and spondyloarthritis (SpA).

Hypothesis 1: A systematic change of diet in line with the Norwegian dietary guidelines, which will result in increased intake of, among other nutrients, omega-3 fatty acids and complete protein, as well as reduced intake of saturated fat and sugar, will improve nutritional status and reduce disease activity.

Hypothesis 2: A systematic change of diet (as above), included a high dose of omega-3 will further improve nutritional status and reduce disease activity compared with placebo.

Design: A DB-RCT-study will be conducted. All patients will receive individualized dietary guidance by a clinical dietician for 12 weeks, before randomization to supplements of omega-3 or placebo, for 24 weeks. The supplement will be blinded for the participants, researchers and physicians.

Clinical implications: The study will investigate the effect of improved diet and nutrition on treatment offered to patients with IRD to provide more evidence-based knowledge, and thus specific dietary guidelines for patients with IRD. In addition, the study might increase the understanding of the role of omega-3 in the pathogenesis of inflammation.

Detailed Description

The study is approved by the Regional Committee for Medical and Health Research Ethics. Participation is voluntary, and informed consent will be requested. Outpatients will be recruited by doctors at the Rheumatology Department at Haukeland University Hospital (HUH). Patients recruited will be included consecutively. The recruitment period will last up to 12 months. Anthropometrical measurements, analysis of body composition, blood tests, clinical parameters, and dietary data will be collected at baseline, and after 12, 24, 36 and 52 weeks.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
120
Inclusion Criteria
  • Patients must be diagnosed with one of the following diagnoses: rheumatoid arthritis, according to the ACR / EULAR 2010 criteria, psoriatic arthritis, according to the CASPAR criteria, axial spondylarthritis, including ankylosing spondylarthritis and non-radiographic spondylarthritis, according to the ASAS criteria
  • Duration of illness ≥0.5 years
  • Between 18 and 75 years
  • Understand Norwegian
  • The patient has given informed consent to participate
  • No change in medication the last 12 weeks before inclusion
Exclusion Criteria

Diagnoses / conditions that make it difficult to follow a dietary intervention and / or supplementation of omega-3s, including:

  • Conditions or use of medications where omega-3 is contraindicated
  • Pregnancy / lactation
  • Allergy to soy or fish
  • Severe liver disease
  • Severe mental or physical illnesses, such as insulin-requiring diabetes

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Placebo capsulesPlacebo (soya)Soya oil
Omega-3Omega-30,9 gram omega-3/capsule x 4 = 3,6 gram omega-3 daily It will be investigated whether diet optimization followed with supplementation of omega-3s can reduce disease activity in patients with inflammatory arthritis. A new omega-3 high concentrate from GC Rieber Oils will be used
Omega-3Dietary guidance0,9 gram omega-3/capsule x 4 = 3,6 gram omega-3 daily It will be investigated whether diet optimization followed with supplementation of omega-3s can reduce disease activity in patients with inflammatory arthritis. A new omega-3 high concentrate from GC Rieber Oils will be used
Placebo capsulesDietary guidanceSoya oil
Primary Outcome Measures
NameTimeMethod
DAS28 (Disease Activity Score 28-joint count)Change between week 0, 12, 24, 36 and 52

Disease activity score, higher values indicate a higher disease activity and below 2.6 meaning remission.

DAPSA (Disease Activity Index for Psoriatic Arthritis)Change between week 0, 12, 24, 36 and 52

Disease activity score, higher values indicate a higher disease activity and below 4 meaning remission

ASDAS-CRP (Ankylosing Spondylitis Disease Activity Score)Change between week 0, 12, 24, 36 and 52

Disease activity score, higher values indicate a higher disease activity

Secondary Outcome Measures
NameTimeMethod
Handgrip strengthChange between week 0, 12, 24, 36 and 52

Nutritional status: Handgrip strength, measured by a dynamometer (kg)

Body compositionChange between week 0, 12, 24, 36 and 52

Estimation of fat mass (kg), fat-free mass (kg), measured by BIA and DXA. Fat-free mass index (kg/m2), and fat-mass index (kg/m2) will be calculated.

BASDAI (Bath Ankylosing Spondylitis Disease Activity Index)Change between week 0, 12, 24, 36 and 52

Disease activity scores and scores evaluating quality of life, range 0-10, and higher values indicate higher disease activity

BASFI (Bath Ankylosing Spondylitis Functional Index)Change between week 0, 12, 24, 36 and 52

Disease activity scores and scores evaluating quality of life, range 0-10, and higher values indicate a higher grade of disability

Dietary intake of macro- and micronutrients, based on a 24h recall.Week 0, 12, 24, 36, 52

Energy (E%, kcal) proteins (g and E%) ratio of fatty acids fibers (g) Vitamins and minerals

Blood lipid profileChange from week 0, 12, 24, 36 and 52

HDL (mmol/L) LDL (mmol/L) total cholesterol (mmol/L) triglycerides (mmol/L)

Waist circumferenceChange between week 0, 12, 24, 36 and 52

Nutritional status: Waist circumference (cm)

MHAQ (Modified Health Assessment Questionnaire)Change between week 0, 12, 24, 36 and 52

Disease activity scores and scores evaluating quality of life, range from 0 to 3 while higher values indicate a higher grade of disability

CDAI (Clinical Disease Activity Index)Change between week 0, 12, 24, 36 and 52

Disease activity scores and scores evaluating quality of life, range 0-76, and scores below 2.8 indicate remission

Dietary intake of macro- and micronutrients, based on a dietary registration of 7 daysWeek -1,10, 50

Energy (E%, kcal) proteins (g and E%) ratio of fatty acids fibers (g) Vitamins and minerals

BMI (Body Mass Index)Change between week 0, 12, 24, 36 and 52

Nutritional status: Weight (kg) and height (m) will be combined to report BMI (kg/m\^2) Change in BMI, waist circumference, fat mass (kg), fat-free mass (kg), fat-free mass index (kg/m2), fat-mass index (kg/m2), handgrip strength

RAID (Rheumatoid Arthritis Impact of Disease)Change between week 0, 12, 24, 36 and 52

Disease activity scores and scores evaluating quality of life, range 0-10, and higher scores indicate a higher grade of disability

RAND12 (short form health survey)Change between week 0, 12, 24, 36 and 52

Disease activity scores and scores evaluating quality of life

Consumption of medicine after 12 monthsChange between baseline and week 52

The proportion who must start or change biological treatment, use of NSAIDs and steroids

Trial Locations

Locations (1)

Haukeland University Hospital

🇳🇴

Bergen, Vestland, Norway

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