The aim was to study whether dietary quality was associated with disease activity and inflammation among patients with rheumatoid arthritis (RA). This cross-sectional analysis included 66 Swedish participants, who each completed a food frequency questionnaire (FFQ) at screening. Food intake was scored by a dietary quality index created by the Swedish National Food Agency. Disease activity was measured as Disease Activity Score 28 (DAS28), based on erythrocyte sedimentation rate (ESR), a patient administered visual analogue scale of perceived global health and the number of tender and swollen joints out of 28 examined. Inflammation was measured as ESR and C-reactive protein (hs-CRP). Associations between dietary quality, disease activity and inflammation were evaluated using multivariable linear regression analysis. High dietary quality (high intake of fish, shellfish, whole grain, fruit and vegetables and low intake of sausages and sweets) was not related to DAS28 (B = -0.02, p = 0.787). However, dietary quality was significantly negatively associated with hs-CRP (B = -0.6, p = 0.044) and ESR (B = -2.4, p = 0.002) after adjusting for body mass index, age, education, smoking and gender. Both hs-CRP and ESR decreased with increasing dietary quality. In conclusion, among patients with RA, high dietary quality was associated with reduced inflammation but not with disease activity.
Keywords: C-reactive protein; blood sedimentation; diet; inflammation; rheumatoid arthritis.