Sources of discrepancy in patient and physician global assessments of rheumatoid arthritis disease activity.

OBJECTIVE: To investigate discrepancy in the perception of rheumatoid arthritis (RA) disease activity between patient and physician, and its possible sources.
METHODS: Eighty patients with RA rated their level of disease activity on a visual analog scale (VAS). Physician global assessment (MDGA) of disease activity was performed blinded to the patient evaluation except for the results of laboratory tests. A discrepancy score (DS) was calculated by subtracting MDGA from patient global assessment (PTGA), leading to definition of 3 groups of patients: (1) no discrepancy when PTGA and MDGA were within 1.0 or 3.0 cm of each other; (2) negative discrepancy when PTGA was under-rated relative to the physician; and (3) positive discrepancy when PTGA was over-rated relative to the physician. Age, sex, disease duration, education, income, residence area, employment, use of antirheumatic drugs, comorbidity, pain score, Health Assessment Questionnaire (HAQ) rating, tender (TJC) and swollen (SJC) joint count, and Disease Activity Score (DAS28) were recorded.
RESULTS: Negative discrepancy was found in 27.5% (VAS 1 cm) and 8.7% (VAS 3 cm) of patients, positive discrepancy in 43.7% (VAS 1 cm) and 23.7% (VAS 3 cm), and no discrepancy in 28.7% (VAS 1 cm) and 67.5% (VAS 3 cm). Patients were predominantly older (mean age near 50 yrs), female, with long disease duration and low income. The negative discrepancy group had a lower level of education and higher C-reactive protein (p < 0.05). The positive discrepancy group presented a higher pain score, HAQ score, and TJC (p < 0.0001). The no-discrepancy group had lower SJC (p < 0.05).
CONCLUSION: Our results indicate that for disease activity in patients with RA assessed on pain score, HAQ, and TJC, the only important feature that determined perception of their RA disease activity was education.