FATIGUE INDEX IN RHEUMATOID ARTHRITIS: CORRELATION WITH CDAI AND RAPID3

Abstract

Background: Fatigue is a major and disabling symptom of rheumatoid arthritis (RA), often persisting despite controlled inflammation. Its relationship with composite disease activity indices remains incompletely understood. Objectives: To evaluate the correlation between fatigue and disease activity indices (CDAI and RAPID3) and to identify predictors of fatigue severity in a real-world RA cohort. Methods: A cross-sectional study of 160 RA patients fulfilling 2010 ACR/EULAR criteria was conducted. Fatigue was assessed using the FACIT-F and VAS scales; disease activity by CDAI and RAPID3. Depression (PHQ-9) and sleep quality (PSQI) were included as covariates. Correlations were analyzed using Spearman’s coefficient, and multivariable regression identified independent predictors. Results: Mean CDAI and RAPID3 were 17.2 ± 7.6 and 4.9 ± 2.1, respectively; mean FACIT-F was 30.8 ± 8.5. Fatigue correlated strongly with RAPID3 (ρ = −0.61, p < 0.001) and moderately with CDAI (ρ = −0.46, p < 0.001). In adjusted models, RAPID3 (β = −0.52, p < 0.001), pain, and depressive symptoms independently predicted fatigue (adjusted R² = 0.584). Conclusions: Fatigue in RA is multifactorial and correlates more closely with patient-reported indices than with physician-assessed activity, emphasizing the need for holistic, patient-centered management