Oklahoma University Health Sciences Center Oklahoma City, Oklahoma, United States
Disclosure(s): No financial relationships with ineligible companies to disclose
Background/Purpose: Rheumatoid arthritis (RA) patients have higher body fat percentages, particularly in the abdominal region, which is associated with increased systemic inflammation. Obesity is associated with changes in plasma fatty acid composition, which can affect inflammatory responses. Omega-3 polyunsaturated fatty acids (n3-PUFA) are precursors for anti-inflammatory oxylipins while the roles of n6 PUFAs and monounsaturated fatty acids (MUFAs) remain less well understood. The goal of this study was to investigate FFA composition of plasma of patients with RA and its associations with RA disease activity. Methods: Cross-sectional study involving 52 RA patients and 30 age-, sex-, and BMI-matched non-RA controls. Participants were evaluated for body mass index (BMI), healthy eating index (HEI), and lipid plasma fatty acid composition after an overnight fast. RA disease activity was assessed using the Clinical Disease Activity Index (CDAI). The correlation between plasma FFAs and CDAI was examined using univariate, Spearman correlation and multivariate linear regression analyses. Results: Among RA subjects, plasma levels of MUFAs [palmitoleic acid (p=0.022), oleic acid (p=0.001), and gondoic acid (p=0.048)] were higher compared to controls. In contrast, plasma levels of n6 PUFAs [linoleic acid (p=0.031) and arachidonic acid (0.004)] were higher in controls compared to RA patients. Oleic acid (r = 0.349, p = 0.013) and gondoic acid (r = 0.435, p = 0.002) showed significant correlations with CDAI. Correlation analyses showed oleic acid (r = 0.349, p = 0.013) and gondoic acid (r = 0.435, p = 0.002) significantly correlated with CDAI. Multivariate linear regression analyses revealed CDAI was independently associated with oleic acid (β = 0.09, 95% CI = 0.02-0.16, p = 0.014) and gondoic acid (β = 0.0012, 95% CI = 0.0005-0.0020, p = 0.002), after adjusting for age, sex, BMI, and HEI.
Conclusion: The findings suggest a potential association between elevated plasma MUFAs and disease activity in patients with RA.
