THE PREVALENCE AND MEANING OF FATIGUE IN RHEUMATIC DISEASE

Objective. To determine the prevalence of fatigue in rheumatic disease ; to characterize the strength of associations between demographic and clinical features and fatigue; to identify predictors of fatigue, and to determine the consequence of clinically significant fatigue. Metho ds, 1488 consecutive patients with rheumatic disease were assessed wit h the Clinical Health Assessment Questionnaire, a health status instru ment with scales for fatigue, pain, global severity, sleep disturbance , gastrointestinal problems, anxiety, depression, health status, healt h satisfaction, and work ability. All patients underwent rheumatic dis ease examinations and laboratory testing. Results, Fatigue measured by visual analog scale (VAS) was present in 88-98% of patients, but clin ically important levels of fatigue (greater than or equal to 2.0 on VA S) were present in more than 41% of patients with rheumatoid arthritis (RA) or osteoarthritis (OA) and 76% of those with fibromyalgia (FM). Fatigue was related to almost all demographic and clinical variables, but in multivariate analyses the strongest independent predictors of f atigue were pain, sleep disturbance, depression, tender point count an d Health Assessment Questionnaire (HAQ) disability, About 90% of the R (2) Of the model (all patients=0.51, RA=0.49, OA=0.45, FM=0.41) was ex plained by pain, sleep disturbance, and depression. In RA assessed by erythrocyte sedimentation rate, joint count and grip strength, no asso ciation of the inflammatory process with fatigue could be found in the multivariate analyses. In measuring health status, fatigue was strong ly associated with work dysfunction and general measures of health (VA S of global severity, health status, and health satisfaction). Conclus ion. Fatigue is common across all rheumatic diseases, associates with all measures of distress, and is a predictor of work dysfunction and o verall health status. The correlates of fatigue are generally similar across RA, OA and FM. Fatigue assessment adds much to understanding an d management of patients and diseases.