OBJECTIVES: To determine whether rheumatoid factors (RFs), measured as continuous variables by time resolved fluoroimmunoassay, reflect disease activity in @entity309 ( @entity309 ). Further, to study the association of RFs and other disease activity parameters with @entity16 , especially in individual @entity1 . METHODS: In active, early @entity309 , IgM and IgA RFs, as well as erythrocyte sedimentation rate (ESR), @entity1851 ( @entity1851 ), tender joint score, and swollen joint score were assessed regularly. At the study start and at 56 and 80 weeks, radiographs of hands and feet were assessed by the Sharp score (van der Heijde modification). Associations between RFs and disease activity parameters were studied. In addition, associations between radiographic damage and disease activity parameters (baseline and time integrated) were analysed by non-parametric tests and multiple regression analysis. The relation between time integrated disease activity parameters and @entity16 in individual @entity1 was analysed and visualised. RESULTS: 155 @entity1 were included. RF levels were strongly associated with the disease activity parameters (especially ESR and @entity1851 ) and with each other. All disease activity parameters, at baseline as well as time integrated parameters, were associated with (the progression of) radiographic damage. Moreover, in individual @entity1 , a linear relationship between time integrated disease activity parameters and progression of @entity16 was seen. CONCLUSION: RFs, measured as continuous variables, can be considered as disease activity parameters in @entity1 with @entity309 . The level of RF at baseline and the exposure to RF over time is associated with @entity16 . In individual @entity1 , there is a constant relation between disease activity and @entity16 .

Rheumatoid factor measured by fluoroimmunoassay: a responsive measure of XXXX activity that is associated with @entity16 .

@entity1 :: ('9606', 'Species') :: ['patients'] @entity16 :: ('MESH:D009422', 'Disease') :: ['radiological joint damage', 'radiological damage'] @entity309 :: ('MESH:D001172', 'Disease') :: ['rheumatoid arthritis', 'RA'] @entity1851 :: ('1401', 'Gene') :: ['C reactive protein', 'CRP']
@entity309 :: (MESH:D001172,Disease) :: ['rheumatoid arthritis disease']
