Can remission in rheumatoid arthritis be assessed without laboratory tests or a formal joint count? possible remission criteria based on a self-report RAPID3 score and careful joint examination in the ESPOIR cohort.

OBJECTIVE

To explore 5 possible criteria for remission in rheumatoid arthritis (RA) based on a patient self-report index, the Routine Assessment of Patient Index Data (RAPID3), with a careful joint examination and possible physician global estimate (DOCGL), but without a formal joint count or laboratory test.

METHODS

The ESPOIR early RA cohort of 813 French patients recruited in 2002-2005 was analyzed to identify patients in remission 6 months after enrollment, according to 2 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) criteria: Boolean ≤ 1 for total tender joint count-28, swollen joint count-28, C-reactive protein, and patient global estimate (PATGL), and Simplified Disease Activity Index (SDAI) ≤ 3.3. Agreement with 7 other remission criteria was analyzed - Disease Activity Score-28 (DAS28) ≤ 2.6, Clinical Disease Activity Index (CDAI) ≤ 2.8, and 5 candidate criteria based on RAPID3, joint examination, and DOCGL: "RAPID3R" (RAPID3 ≤ 3.0); "RAPID3R+SJ1" (RAPID3 ≤ 3.0, ≤ 1 swollen joint); "RAPID3R+SJ1+D1" (RAPID3 ≤ 3.0, ≤ 1 swollen joint, DOCGL ≤ 1); "RAPID3R+SJ0" (RAPID3 ≤ 3.0, 0 swollen joints); and "RAPID3R+SJ0+D1" (RAPID3 ≤ 3.0, 0 swollen joints, DOCGL ≤ 1), according to kappa statistics, sensitivity, and specificity. Residual global, articular, and questionnaire abnormalities according to each criteria set were analyzed.

RESULTS

Among 813 ESPOIR patients, 720 had complete data to compare all 9 possible criteria. Substantial agreement with the Boolean criteria was seen for SDAI, CDAI, RAPID3R+SJ1, RAPID3R+SJ1+D1, RAPID3R+SJ0, and RAPID3R+SJ0+D1 (92.2%-94.7%, kappa 0.67-0.79), versus only moderate agreement for DAS28 or RAPID3R (79.9%-85.8%, kappa 0.46-0.55).

CONCLUSION

Remission according to CDAI and RAPID3R+SJ1, but not DAS28 or RAPID3R, is similar to that of the ACR/EULAR criteria. RAPID3 scores require a complementary careful joint examination for clinical decisions, do not preclude formal joint counts or other indices, and may be useful in busy clinical settings.