Clinical trial NCT00638950: A Long-term Moderate Intervention With n-3 LC-PUFA-supplemented Dairy Products in Patients With Rheumatoid Arthritis
Official title: Long-term Moderate Intervention With n-3 LC-PUFA-supplemented Dairy Products: Effects on Pathophysiological Biomarkers in Rheumatoid Arthritis
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Rheumatoid Arthritis
Keywords: n-3 LC-PUFA
Rheumatoid arthritis
disease activity
inflammation
oxidative stress
immune system
Lead sponsor: University of Jena
Sponsor class: OTHER
First posted: 2008-03-19
Enrollment: 45
Sex: ALL
Minimum age (years): 35
Maximum age (years): 74
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: TREATMENT

Brief summary: The effects of n-3 LC-PUFA-supplemented dairy products on inflammation and immunological parameters, biomarkers of oxidative stress, serum lipids, and disease activity were determined in patients with rheumatoid arthritis (RA).

Detailed description: Recent studies suggest that n-3 LC-PUFA may improve cardiovascular and inflammatory diseases.

As a precondition for participating in this study, the subjects were provided information in writing and verbally about the details of the study. Informed consent was obtained from all volunteers. Before the beginning of the study, all participants were subject to a medical examination in the Clinic for Rheumatology (Internal Medicine III, Friedrich Schiller University, Jena). The RA was diagnosed according to the 1987 revised criteria of the American Rheumatism Association (ARA). Severity of disease activity was evaluated by using the disease activity score DAS 28.

Forty five subjects (43 f, 2 m) were randomly divided into two groups to carry out a double-blind, placebo-controlled cross-over study.

The study consisted of two investigation periods of 12 weeks, with an eight-week washout period in between. Patients received about 40 g fat daily (200 g yoghurt with 3.8% fat, 30 g cheese with about 50% fat in the dry matter, and 20-30 g butter). The milk fat was partially exchanged by special oils with high amounts of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha linoleic acid (ALA). The daily dose of n-3 FA amounted to 2.4 g, consisting of 1.1 g ALA, 0.7 g EPA, 0.1 g DPA, and 0.4 g DHA. The placebo products were commercial dairy products with comparable fat contents.

Venous blood and 24h urine were collected at the beginning and at the end of each period. The DAS 28 score was assessed at the beginning and the end of each period, respectively.

Eligibility criteria: Inclusion Criteria:

* Clear diagnosis of Rheumatoid Arthritis
* Patients receiving nonsteroidal anti-inflammatory drugs (NSAID) or corticosteroids (max. 15 mg/d) or both were eligible if dosage had been stable for at least 4 weeks before day 1 of the study and remained below this limit throughout the study
* Patients on disease-modifying antirheumatic drugs (DMARD) had to be on a constant dosage for at least 8 weeks before and throughout the study

Exclusion Criteria:

* Subjects with gastrointestinal or metabolic diseases, alcohol abuse, taking dietary supplements (e. g. fish oil capsules), known allergies or foodstuff indigestibility
* patient's request, serious infections, inadequate control of arthritis symptoms (over 50% increase of the number of swollen or tender joints), reinstitution of therapy with DMARD, or if patient compliance with the study protocol was doubtful.

Primary outcomes:
measure: disease activity score DAS28
timeFrame: 12 weeks
measure: inflammatory markers (c-reactive protein, erythrocyte sedimentation rate)
timeFrame: 12 weeks
Secondary outcomes:
measure: cellular and humoral immunological parameters (CDs)
timeFrame: 12 weeks
measure: COX expression
timeFrame: 12 weeks
measure: biomarkers of oxidative stress (8-iso-prostaglandin F2α, 15-keto-dh prostaglandin F2α, 8-oxo-deoxy-guanosine)
timeFrame: 12 weeks
measure: hydroxypyridinium crosslinks
timeFrame: 12 weeks
Other outcomes:
Locations:
city: Jena
country: Germany
facility: University of Jena, Institute of Nutrition, Department of Nutritional Physiology
state: Thuringia
Study officials:
affiliation: University of Jena, Dept. of Nutritional Physiology
name: Gerhard Jahreis, Prof. Dr.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Dawczynski C, Schubert R, Hein G, Muller A, Eidner T, Vogelsang H, Basu S, Jahreis G. Long-term moderate intervention with n-3 long-chain PUFA-supplemented dairy products: effects on pathophysiological biomarkers in patients with rheumatoid arthritis. Br J Nutr. 2009 May;101(10):1517-26. doi: 10.1017/S0007114508076216. Epub 2009 Feb 27.