RESUMO
OBJECTIVES: Fatigue is one of the most prevalent and disabling symptoms among patients with rheumatoid arthritis (RA), however, it is frequently neglected by health professionals. This study aimed to develop a multidimensional explanatory model of fatigue in patients with RA as a basis for better understanding and intervention. METHODS: This was an ancillary analysis of an observational, cross-sectional, single centre study. Patients completed a questionnaire including demographic data and measures of pain, sleep, disability, anxiety, depression, and personality. Fatigue was assessed by the Functional Assessment of Chronic Illness Therapy - Fatigue (FACIT-F). Disease activity and haemoglobin levels were assessed. Path analysis was performed to test and improve a hypothesised model for fatigue. RESULTS: This analysis included 142 patients, with a mean (SD) age of 61.1 (11.7) years. The final path analysis model presented acceptable fit and explained 60.0% of the variance of fatigue. The predominant direct explanatory factors identified were disability (46.5%) and depression (41.2%), the latter having an additional indirect influence of 19% through disability. Age (-16.2%) and sleep disturbance (15.7%) were also directly linked to fatigue. Personality trait extroversion (-22.4%), pain (20.0%), and disease activity (14.9%) are only indirectly related to fatigue. CONCLUSIONS: Depression, disability and sleep disturbance appear to be the main factors explaining fatigue in patients with RA. Disease activity, pain, and personality seem to play only a secondary role, extroversion being the only personality trait associated with fatigue. These findings foster a shift in the paradigm of care towards a more holistic management of fatigue, integrating adjunctive therapies beyond measures targeted solely at disease remission.