Some RA Remission Criteria Underestimate Foot Synovitis
Only 1981 ACR and proposed 2011 ACR/ EULAR criteria include it in remission classification
THURSDAY, Dec. 15 (HealthDay News) -- For patients with rheumatoid arthritis (RA), remission criteria based on 28 joint counts underestimate foot involvement, compared with criteria which assess full joint counts, according to a study published online Dec. 1 in Arthritis & Rheumatism.
Mihir D. Wechalekar, M.B.B.S., M.D., from the Queen Elizabeth Hospital in Adelaide, Australia, and colleagues investigated whether remission criteria underestimated foot involvement in 123 patients with RA, assessed at baseline and after six months in a clinical setting. The 28 joint Disease Activity Score (DAS28), Simplified Disease Activity Index (SDAI), Clinical Disease Activity Index (CDAI), the Boolean-based 1981 American College of Rheumatology (ACR), and the proposed 2011 ACR/ European League against Rheumatism (EULAR) criteria were used to evaluate remission. The prevalence of foot synovitis, and mean foot joint scores, were estimated for patients meeting each of the remission criteria.
The investigators found that, at six months, 1981 ACR and 2011 ACR/EULAR criteria, which utilize full joint counts, classified the least patients as being in remission (12 to 14 percent), with limited evidence of foot synovitis in these patients. However, a substantial proportion of patients (more than 20 percent) who met DAS28, SDAI, CDAI and 2011 ACR/ EULAR criteria (clinical or trial), calculated using 28 joint counts, had foot synovitis. Residual foot synovitis was differentially detected by the new 2011 ACR/EULAR remission criteria.
"Although the DAS28, CDAI, and SDAI have been validated for assessment of remission in RA, their performance in detecting foot synovitis, which they fail to measure directly, is poor, in contrast to ACR and 2011 ACR/EULAR remission criteria," the authors write.