Reduced Serum Maresin-1 in Rheumatoid Arthritis and Fibromyalgia Compared with Healthy Controls: A Cross-Sectional Study

Abstract

Background/Aims: Maresin-1 (MaR-1), a specialized pro-resolving mediator, modulates inflammation and pain signaling. Serum MaR-1 was compared across rheumatoid arthritis (RA), fibromyalgia (FM), and healthy controls and examined its associations with disease activity and pain measures. Materials and Methods: In this cross-sectional study, patients with rheumatoid arthritis (RA) (n = 30), patients with fibromyalgia (FM) (n = 30), and healthy controls (n = 29) were enrolled. Clinical assessments included visual analog scale (VAS) scores for pain and fatigue, DAS28-CRP in the RA group, the PainDETECT questionnaire for neuropathic pain screening in RA patients, the Fibromyalgia Impact Questionnaire (FIQ) in the FM group, and the Beck Depression and Beck Anxiety Inventories (BDI and BAI) to assess emotional status. Serum MaR-1 was quantified by enzyme-linked immunosorbent assay. Group comparisons, correlations, and receiver-operating characteristic analyses were performed. Results: Controls had higher MaR-1 than both patient groups (P < .001). In RA, MaR-1 inversely correlated with VAS pain, DAS28; in FM, MaR-1 inversely correlated with VAS pain (P < .001). Discriminative ability in this cohort (RA): Area under the curve (AUC) 0.941 (95% CI 0.887-0.996), cut-off <= 1.07, sensitivity 86.7%, and specificity 93.1%. Discriminative ability in this cohort (FM): AUC 0.933 (95% CI 0.861-1.000), cut-off <= 1.19, sensitivity 90.0%, specificity 93.1%. Conclusion: Serum MaR-1 is reduced in RA and FM and tracks with pain severity and disease activity, supporting its potential as a biomarker of chronic inflammatory pain biology. Larger longitudinal studies are warranted to establish clinical utility.