Session Information
Title: Rheumatoid Arthritis - Clinical Aspects: Novel Biomarkers and Other Measurements of Disease Activity
Session Type: Abstract Submissions (ACR)
Background/Purpose:
Measuring disease activity in Rheumatoid Arthritis (RA) remains an elusive goal. Both DAS and CDAI have an inherent weakness because similar numbers can result from dissimilar clinical situations. Snapshot, a hands on immediate clinical tool, shows where a patient stands with SJC, TJC, MD and Patient Global, and visualizes the discrepancies between MD and patient assessments. We have validated Snapshot Traditional (SS-T) (SJC-PtGlobal), Snapshot MD (SS-M) (SJC-MD global) and Snapshot Patient (SS-P) (TJC-Pt. global) to DAS28 (ESR), DAS28 (CRP) and CDAI. in 96 Canadian RA patients, at onset, and disease control.
Methods:
We validated Snapshot (SS-T, SS-M and SS-P) in data from 96 patients of active RA using SAS version 9.3. The Snapshot scores were validated against DAS28 (ESR), DAS28 (CRP) and CDAI scores. We used Pearson correlation coefficients to assess the correlation (r) and ordinary linear regression analysis to estimate regression coefficients (β) between Snapshot and other measures (DAS28 and CDAI). We also assessed the extent of agreement between Snapshot and other measures DAS28 using Bland-Altman plots.
Results:
The results revealed direct significant linear correlation of Snapshot with DAS28 and CDAI (r=0.83 with DAS28 (ESR), 0.92 with DAS28 (CRP), 0.94 with CDAI for SS-T, r=0.82 with DAS28 (ESR), 0.91 with DAS28 (CRP), 0.91 with CDAI for SS-P and r=0.70 with DAS28 (ESR), 0.79 with DAS28 (CRP), 0.89 with CDAI for SS-M). In a linear regression model with DAS28 (ESR) as a predictor, regression coefficients (β) were 1.33 (p<0.001), 0.98 (p<0.001) and 1.27 (p<0.001) for SS-T, SS-M and SS-P respectively with good model fit. Bland-Altman plots showed high degree of agreement between Snapshot and DAS28 (ESR) with 96.7% (SS-T), 96% (SS-M) and 95.6% (SS-P) of the observations of the difference between Snapshot and DAS28 lying between mean±2SD. Similar results were observed for change score data (for disease control).
|
|
SS change score (Pt. Global and SJC) |
SS change score (MD Global and SJC) |
SS change score (Pt. Global and TJC) |
|||
|
|
Pearson’s correlation (P-value) |
Regression coefficient (95% confidence interval) |
Pearson’s correlation (P-value) |
Regression coefficient (95% confidence interval) |
Pearson’s correlation (P-value) |
Regression coefficient (95% confidence interval) |
|
DAS28 (ESR) change score |
0.839 (<0.0001) |
1.47 (1.26, 1.68) |
0.751 (<0.0001) |
1.15 (0.93, 1.37) |
0.824 (<0.0001) |
1.32 (1.12, 1.52) |
|
DAS28 (CRP) change score |
0.896 (<0.0001) |
1.68 (1.49, 1.86) |
0.813 (<0.0001) |
1.33 (1.12, 1.53) |
0.885 (<0.0001) |
1.51 (1.34, 1.69) |
|
CDAI change score |
0.915 (<0.0001) |
0.16 (0.14, 0.17) |
0.921 (<0.0001) |
0.14 (0.13, 0.15) |
0.911 (<0.0001) |
0.15 (0.13, 0.16) |
Conclusion:
All Snapshots (SS-T, SS-M, SS-P) validated well with DAS28 and CDAI in measuring RA disease activity with the benefit of one second visual recognition for patient and MD at the clinical visit and without calculation. The discrepancy between MD and patient values is obvious and prompts an alternative therapeutic decision. Some patients understate their disease as compared to their SJC and need more RA therapy, while others overstate because of soft tissue pain, or depression. We prefer Snapshot Traditional. Snapshot offers an immediate and validated clinical tool for doctors and patients allowing better understanding of disease activity and need for therapeutic intervention.
Disclosure:
W. G. Bensen,
None;
W. Bensen,
None;
M. Deamude,
None;
C. Mech,
None;
R. Bensen,
None;
A. N. Lau,
None;
A. Shah,
None.
« Back to 2014 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/validation-of-snapshot-a-rheumatoid-arthritis-assessment-tool-against-cdai-das28-esr-and-das28-crp-in-canadian-patients-with-rheumatoid-arthritis/