RESUMEN
OBJECTIVES: While fatigue is an extremely common complaint of patients with systemic lupus erythematosus (SLE), the information on factors influencing SLE fatigue in the long term is still limited. This study aims to investigate the actual level of physical activity in the daily life of SLE outpatients and its association with fatigue. METHODS: In a cross-sectional survey on 93 SLE outpatients we combined clinical assessment with questionnaires to comprehensively assess SLE fatigue, its impact on function and health-related quality of life (hrQoL), and potential contributing factors, with particular emphasis on physical activity. RESULTS: Fatigue by visual analogue scores and FACIT fatigue scores correlated closely (r=-0.61, p<0.0001). We analysed fatigue in three patient groups, defined by both VAS and FACIT score, as those with severe fatigue, moderate fatigue, and less fatigue. Severe fatigue was associated with greatly diminished hrQoL. SLE patients regularly doing sports showed significantly lower fatigue values than those not doing sports; dog owners were less fatigued than other patients. Fatigue values were not significantly different between employed and unemployed patients. Severe fatigue was also associated with more pain and with shorter sleep duration and worse quality of sleep. DISCUSSION: This study finds a clear association of fatigue with physical activity, but also with pain and sleep disturbance, and reiterates the impact of fatigue on the SLE patients' quality of life.