AB0229 Fatigue in Rheumatoid Arthritis Patients with Low Disease-Activity

Background Unless effective pharmacological treatment for controlling disease-activity in rheumatoid arthritis, the majority of patients report clinically relevant fatigue which challenges the view of disease-activity as main cause of elevated levels of fatigue.
Objectives The primary aim of this study was to analyse the prevalence of fatigue in RA patients with very low disease-activity, by using a novel multidimensional fatigue questionnaire (BRAF-MDQ). As the Dutch version was not yet validated, the second aim was to psychometrically evaluate the Dutch BRAF-MDQ.
Methods Data of 199 RA patients (69% women, mean age 59 years, mean DAS-28 =1.99) were selected from a multi-centre randomized clinical trial. Firstly, the prevalence rates of clinical important levels of fatigue were examined and Spearman Rho correlations were used to determine how fatigue was related to disease-activity. Secondly, the dimensional structure, internal consistency, discriminant validity, distinctiveness, reliability, construct validity and possible floor- and ceiling effects were examined to psychometrically evaluate the BRAF-MDQ.
Results Clinically relevant fatigue was present in 73% of the patients. The correlation coefficients between disease-activity and dimensions of fatigue ranged from 0.05 to 0.09. The dimensional structure of the BRAF-MDQ was broadly confirmed, but major floor effects were detected.
Conclusions The findings indicate that even though RA inflammation is clinically under control, the majority of the patients still reported clinically relevant fatigue. Not all items of BRAF-MDQ are equally suitable for patients with low disease-activity, pointing to possibilities for improving fatigue measurement by, for example, adaptive testing methodologies.