To compare the burden of disease and its development over time in patients referred to an early arthritis cohort who were diagnosed either as having arthralgias without synovitis or as having rheumatoid arthritis (RA).
Patients diagnosed as having arthralgias without synovitis or RA were selected from the Rotterdam Early Arthritis Cohort. Data on clinical and psychological characteristics, demographics, pain scores (Rheumatoid Arthritis Disease Activity Index), functional ability (Health Assessment Questionnaire), health-related quality of life (HRQOL; Short Form 36), fatigue (visual analog scale and Fatigue Assessment Scale), and health care utilization (HCU) were collected at baseline and at 6 and 12 months of followup. The burden of disease measures (pain, functional ability, fatigue, and HRQOL) and HCU levels were plotted over time for both groups. A Poisson regression model for repeated data was used to identify determinants of HCU for both groups.
At baseline, 330 patients with arthralgias without synovitis (nonsynovitis [NS] group) and 244 RA patients (RA group) were included. Overall, the burden of disease measures and HCU levels were very similar between groups. Both groups showed improvement over time with respect to pain scores, functional ability, HRQOL, and HCU levels. Independent predictors of high HCU were identified as more pain, worse physical health, and external locus of control in the NS group and as shorter duration of symptoms, low chance locus of control, and worse physical functioning in the RA group.
Despite the absence of an inflammatory diagnosis, patients with arthralgias without synovitis experienced a similar burden of disease compared with RA patients.