Objectives:To compare the disease activity and the improvement of disease activity evaluated between by Disease Activity Score 28 using ESR (DAS28-ESR) and by DAS28 using CRP (DAS28-CRP) in Japanese patients with rheumatoid arthritis (RA).
Methods: Data from 3073 RA patients registered in the large cohort database (NinJa: National Database of Rheumatic Diseases by iR-net in Japan) of 2003 was used to calculate DAS28-ESR and DAS28-CRP and disease activities were evaluated. Furthermore, improvements of disease activities were evaluated according to the European League Against Rheumatism (EULAR) response criteria in 1482 RA patients whose DAS28-ESR and DAS28-CRP could be calculated from data of both 2002 and 2003.
Results:The mean value of DAS28-CRP (3.59, SD 1.25) was significantly smaller than that of mean DAS28- ESR (4.31, SD 1.32) (p<0.0001). The number of patients who satisfied the criteria of remission was 297 (9.7%) in DAS28-ESR vs 705 (22.9%) in DAS28-CRP and the number of patients with high disease activity was 842 (27.4%) vs 357 (11.6%) for DAS28-ESR and DAS28-CRP, respectively; there was a significant difference between the two (p<0.0001). Change of respective DAS28 was significantly correlated (ΔDAS28-ESR: -0.05, SD 1.14 vs ΔDAS28-CRP: -0.10, SD 1.10) (p< 0.0001); however, the number of 'good response' patients was significantly different (p<0.03) between DAS28-ESR (97 patients, 6.5%) and DAS28-CRP (136 patients, 9.2%).
Conclusions:DAS28-CRP significantly underestimated the disease activity and overestimated the improvement of disease activity compared with DAS28- ESR. DAS28-CRP should be evaluated using different criteria from that for DAS28-ESR.
- The EULAR response criteria
- rheumatoid arthritis