A cross-sectional study of multidimensional fatigue in biologic-treated rheumatoid arthritis: which variables play a role?

Purpose: Despite efficient biological disease-modifying antirheumatic drugs (bDMARDs) Rheumatoid Arthritis (RA) patients still suffer from high fatigue. This study aims to further our knowledge by assessing severity levels of the various fatigue dimensions and their associations with pain, sleep quality, and psychological well-being in bDMARDs treated RA patients. Material and Methods: The sample consisted of 146 RA patients (84.9% females; mean age 56.6 ± 13.6 years), who completed the MFI-20, SF-36, PSQI, GAD-7 and PHQ-9. Correlation analyses and multiple linear regressions were used to analyse the data. Results: General fatigue was the highest reported type of fatigue, followed by physical fatigue dimensions. In the final regression model, pain and disability were significantly associated with physical fatigue (p ≤ 0.001, p ≤ 0.05, respectively) and reduced activity (p ≤ 0.01, p ≤ 0.05, respectively). Anxiety was significantly associated with mental fatigue (p ≤ 0.05) and reduced motivation (p ≤ 0.01). Regression analyses showed no significant associations between depression, sleep quality, and fatigue in any of the final models. Conclusions: Our findings indicate that effectively addressing fatigue in RA patients requires an individualized approach. This approach should acknowledge the varying degrees of fatigue across different fatigue dimensions (physical or mental), while also taking into account the patient’s mental health problems, pain levels, and disability levels.