Intake frequency of vegetables or seafoods negatively correlates with disease activity of rheumatoid arthritis.

To clarify the relationship between dietary habit and disease activity of rheumatoid arthritis (RA). This study enrolled RA patients who met the ACR/EULAR 2010 classification criteria from Kyoto University Rheumatoid Arthritis Management Alliance (KURAMA) cohort in 2015. 22-item food frequency questionnaire (FFQ) was taken for the measurement of dietary habit in a single-institution cohort of RA (Kyoto University Rheumatoid Arthritis Management Alliance: KURAMA) in 2015. The disease activities of RA using the Disease Activity Score calculated based on the erythrocyte sedimentation rate (DAS28-ESR), Simplified Disease Activity Index (SDAI), Health Assessment Questionnaire (HAQ), and serum matrix metalloproteinase-3 (MMP-3) level, the use of disease-modifying anti-rheumatic drugs (DMARDs), disease duration, rheumatoid factor, anti-cyclic citrullinated antibody, and body mass index were also examined. All of them were combined and statistically analyzed. 441 RA patients (81% women; mean age 65 years; mean disease duration 15 years) were enrolled from the KURAMA cohort. Average Disease Activity Score-28 using the erythrocyte sedimentation rate (DAS28-ESR) was 2.7. Univariate analysis showed that intake frequency of vegetables had a statistically significant negative correlation with disease activity markers, such as DAS28-ESR (ρ = -0.11, p<0.01), Simplified Disease Activity Index (SDAI) (ρ = -0.16, p<0.001), matrix metalloproteinase-3 (MMP-3) (ρ = -0.21, p<0.0001), and Health Assessment Questionnaire (HAQ) (ρ = -0.13, p<0.01). Factor analysis with varimax rotation was done to simplify the relevance of disease activity to various food items. 22 foods were categorized into five dietary patterns: "seafoods", "vegetables/fruits", "meats/fried foods", "snacks", and "processed foods". The multivariate analysis adjusted for clinically significant confounders showed that "seafoods" had statistically significant negative correlations with DAS28-ESR (β = -0.15, p<0.01), SDAI (β = -0.18, p<0.001), MMP-3 (β = -0.15, p<0.01), and HAQ (β = -0.24, p<0.0001). "Vegetables/fruits" had statistically significant negative correlations with SDAI (β = -0.11 p<0.05), MMP-3 (β = -0.12, p<0.01), and HAQ (β = -0.11, p<0.05). These results suggest that high intake frequency of vegetables/fruits and/or seafoods might correlate with low disease activity.

Déclaration de conflit d'intérêts

I.M. has declared no conflicts of interests. K.M. has received speaking fees, and/or consulting fees from Eisai Co. Ltd. M.H. received research grant and/or speaker fee from Astellas, Eisai, Tanabe-Mitsubishi, and Brystol-Meyers. T. M. received research grants and/or speaking fees from Asahikasei Pharma Corp., Astellas Pharma Inc., AYUMI Pharmaceutical Corp., Bristol-Myers Squibb, Chugai Pharmaceutical Co, Ltd., Diaichi-Sankyo Co.,Ltd., Eisai Co., Ltd., Eli Lilly Japan K.K., Mitsubishi-Tanabe Pharma Co., Pfizer Japan Inc., Sanofi K.K. and Takeda Pharmaceutical Co., Ltd.. These companies had no role in the design of the study, the collection or analysis of the data, the writing of the manuscript or decision to submit the manuscript for the publication. This does not alter our adherence to PLOS ONE policies on sharing data and materials.