Validation of the 28-joint Disease Activity Score (DAS28) and European League Against Rheumatism response criteria based on C-reactive protein against disease progression in patients with rheumatoid arthritis, and comparison with the DAS28 based on erythrocyte sedimentation rate

• Published in: Annals of the rheumatic diseases Vol. 68; no. 6; pp. 954 - 960
• Main Authors: Wells, G, Becker, J-C, Teng, J, Dougados, M, Schiff, M, Smolen, J, Aletaha, D, van Riel, P L C M
• Format: Journal Article
• Language: English
• Published: London BMJ Publishing Group Ltd and European League Against Rheumatism 01.06.2009; BMJ Publishing Group; BMJ Publishing Group LTD
• Series: Extended report
• Subjects: Abatacept; Acute Disease; Adult; Agreements; Antirheumatic Agents - therapeutic use; Arthritis, Rheumatoid - blood; Arthritis, Rheumatoid - diagnostic imaging; Arthritis, Rheumatoid - drug therapy; Arthrography; Biological and medical sciences; Biomarkers - blood; Blood Sedimentation; C-Reactive Protein - analysis; Clinical and Epidemiological Research; Clinical Trials, Phase III as Topic; Datasets; Disease Progression; Diseases of the osteoarticular system; Female; Humans; Immunoconjugates - therapeutic use; Inflammatory joint diseases; Male; Medical sciences; Middle Aged; Miscellaneous. Osteoarticular involvement in other diseases; Randomized Controlled Trials as Topic; Reproducibility of Results; Rheumatism; Rheumatoid arthritis; Severity of Illness Index; Treatment Outcome; Tumor necrosis factor-TNF; Validity; Human; Immunopathology; Prognosis; Evaluation scale; Activity index; Diseases of the osteoarticular system; Rheumatology; Autoimmune disease; Inflammatory joint disease; Chronic; Sedimentation rate; Rheumatoid arthritis; Arthropathy; Evolution; C reactive protein; Comparative study
• ISSN: 0003-4967; 1468-2060
• DOI: 10.1136/ard.2007.084459

Objective:To validate and compare the definition of the Disease Activity Score 28 based on C-reactive protein (DAS28 (CRP)) to the definition based on erythrocyte sedimentation rate (ESR).Methods:Data were analysed from two randomised, double-blind, placebo-controlled trials of abatacept of 6-month and 12-month duration in patients with rheumatoid arthritis. European League Against Rheumatism (EULAR) response criteria and the proportion of patients in remission (DAS28 <2.6) based on the two DAS28 definitions were examined. Trends in radiographic progression (erosion score, joint space narrowing score and total score) and physical function (Health Assessment Questionnaire Disability Index (HAQ-DI)) across the EULAR responder states (none, moderate and good) were analysed.Results:There was general agreement in determining the EULAR responder state using both DAS28 definitions (κ = 0.80, 95% CI 0.76 to 0.83). Overall, there was 82.4% agreement on the EULAR response criteria; when disagreements occurred, the DAS28 (CRP) yielded a better EULAR response more often then DAS28 (ESR) (12.6% vs 4.9%, respectively). There was also agreement in determining remission: κ = 0.69 (95% CI 0.60 to 0.78). Radiographic progression decreased in patients treated with abatacept across EULAR states (from none to moderate to good) based on both definitions. For patients treated with placebo, the trend was not as pronounced, with radiographic scores higher for moderate vs non-responders. For physical function, similar trends were observed across the EULAR states for both DAS28 definitions.Conclusions:The DAS28 (CRP) has been validated against radiographic progression and physical function. While the DAS28 (CRP) yielded a better EULAR response more often than the DAS28 (ESR), the validation profile was similar to the DAS28 (ESR), indicating that both measures are useful for assessing disease activity in patients with rheumatoid arthritis.