Background Many patients with rheumatoid arthritis (RA) report symptom relief from certain foods. Earlier research indicates positive effects of food and food components on clinical outcomes in RA, but insufficient evidence exists to provide specific dietary advice. Food components may interact but studies evaluating combined effects are lacking. Objectives We aimed to investigate if an anti-inflammatory diet reduces disease activity in patients with RA. Methods In this single-blinded crossover trial, 50 patients with RA were randomly assigned to an intervention diet containing a portfolio of suggested anti-inflammatory foods, or a control diet similar to the general dietary intake in Sweden, for 10 wk. After a 4-mo washout period the participants switched diet. Food equivalent to ∼50% of energy requirements was delivered weekly to their homes. For the remaining meals, they were encouraged to consume the same type of foods as the ones provided during each diet. Primary outcome was change in Disease Activity Score in 28 joints-Erythrocyte Sedimentation Rate (DAS28-ESR). Secondary outcomes were changes in the components of DAS28-ESR (tender and swollen joints, ESR, and visual analog scale for general health) and DAS28-C-reactive protein. Results In the main analysis, a linear mixed ANCOVA model including the 47 participants completing ≥1 diet period, there was no significant difference in DAS28-ESR between the intervention and control periods (P = 0.116). However, in unadjusted analyses, DAS28-ESR significantly decreased during the intervention period and was significantly lower after the intervention than after the control period in the participants who completed both periods (n = 44; median: 3.05; IQR: 2.41, 3.79 compared with median: 3.27; IQR: 2.69, 4.28; P = 0.04, Wilcoxon's Signed Rank test). No significant differences in the components were observed. Conclusions This trial indicates positive effects of a proposed anti-inflammatory diet on disease activity in patients with RA. Additional studies are required to determine if this diet can cause clinically relevant improvements. This trial was registered at clinicaltrials.gov as NCT02941055.

Background:Many patients with rheumatoid arthritis (RA) experience symptom relief of certain foods and earlier research has shown positive effects of food and food components on clinical outcomes of RA. Food components may potentiate each other in their effects on RA, but even so, studies combining foods and food components with probable effects on RA are scarce. Furthermore, comorbidities are common in RA and the risk of cardiovascular disease is elevated in this group. Assumed mechanisms include classical risk factors such as systemic inflammation, dyslipidemia as well as an unfavorable body composition.Objectives:We investigated if a diet combining foods with anti-inflammatory effects, i.e. an anti-inflammatory portfolio diet, could reduce RA disease activity, markers of inflammation, body composition and blood lipid levels compared to a control diet.Methods:In this controlled cross-over trial, 50 patients with RA were randomized to start with either intervention or control diet for ten weeks followed by a wash-out period of four months. The intervention diet was an anti-inflammatory portfolio diet containing foods rich in omega-3 fatty acids, fibers and probiotics. The control diet was a typical Swedish diet. Food equivalent to 50% of daily energy needs was delivered home weekly. For the remaining intake, participants were instructed to consume similar foods as the study diet regimen. Primary outcome measure was change in DAS28, using ESR. Secondary outcomes included changes in blood lipid levels, ESR and CRP as well as body composition.Results:No significant difference in DAS28 between the groups was seen using Mixed Models analyze (p=0.116). However, DAS28 was significantly lower after the intervention diet compared to after control diet (p=0.04) and a significant reduction over time was seen in the intervention group (p=0.012) using Wilcoxon signed rank test. HDL-cholesterol was increased and TG were lowered after intervention compared to control, analyzed using Mixed Models (p=0.046 and p=0.006 respectively). In addition, there was a non-significant trend towards lowered LDL-cholesterol (p=0.077). Comparing after intervention to after control, there were non-significant lower weight, BMI and fat mass after the intervention (p=0.077, p=0.075 and p=0.058 respectively). None of the other outcomes changed significantly between groups.Conclusion:This study showed positive effects on disease activity and blood lipid levels of a diet combining foods with anti-inflammatory properties, but the results must be confirmed in larger studies.References:[1] Agca R, et al. EULAR recommendations for cardiovascular disease risk management in patients with rheumatoid arthritis and other forms of inflammatory joint disorders: 2015/2016 update. Annals of the rheumatic diseases. 2017;76(1):17-28.[2] Piepoli MF, et al. 2016 European Guidelines on cardiovascular disease prevention in clinical practice: The Sixth Joint Task Force of the European Society of Cardiology and Other Societies on Cardiovascular Disease Prevention in Clin...