Beyond Pain Intensity: Central Sensitization and Psychosocial Symptom Burden in Women with Rheumatoid Arthritis

Background and Objectives: Persistent pain in rheumatoid arthritis (RA) may reflect mechanisms not fully captured by systemic inflammatory markers. This study estimated the frequency of elevated Central Sensitization Inventory (CSI) scores in women with RA and examined associations with pain, fatigue, depressive symptoms, function, inflammatory markers, and disease activity. Materials and Methods: This prospective single-center observational cohort included 97 female inpatients who completed a standardized three-week rehabilitation program. The CSI was used as a symptom-based screening instrument. Pain, function, fatigue, and depressive symptoms were assessed with the Visual Analog Scale (VAS), Health Assessment Questionnaire (HAQ), FACIT-Fatigue scale, and Beck Depression Inventory-II (BDI-II), respectively. Results: Fifty-seven participants (58.8%) had CSI scores ≥ 40. Higher CSI scores were associated with greater pain, more depressive symptoms, more fatigue, and higher DAS28-CRP scores, but not with ESR, CRP, IL-6, or disease duration. In adjusted baseline models, the association with VAS pain was statistically significant but modest (unstandardized beta = 0.024 per CSI point; standardized beta = 0.273). Across the three-week follow-up, VAS pain decreased by 2.53 points; mean FACIT-Fatigue and HAQ changes were smaller than commonly cited clinically important thresholds, and CSI changed only modestly. In adjusted multivariable models, higher CSI scores remained independently associated with VAS pain, FACIT-Fatigue, and BDI-II scores, whereas no significant association was found with HAQ. CSI was not associated with CRP, IL-6, or disease duration. Conclusions: In this cohort of women with RA, elevated CSI scores identified a greater self-reported symptom burden and were independently associated with pain, fatigue, and depressive symptoms after adjustment, though the pain association remained modest in magnitude. No meaningful association was found with functional disability. The uncontrolled, single-arm design and restricted inflammatory-marker range preclude causal conclusions or proof that symptoms were independent of inflammation.