Background/Purpose: Several
sets of remission criteria have been developed. The ACR/EULAR criteria were
validated against their potential to predict prognosis of rheumatoid arthritis
(RA) [1]. Duration of remission was not studied, but is likely to be an even
better predictor of RA prognosis. We investigated whether remission at one point
in time and sustained remission during 26, 52 and 78 weeks of treatment are
predictive of RA prognosis in early RA patients after 104 weeks of treatment.

Methods: In the COBRA-light trial [2,3], patients were
assessed for remission according to Boolean, SDAI, CDAI, RAPID, DAS44 and DAS28
criteria at 26, 52, 78 and 104 weeks of treatment. ‘Sustained’ was defined as
remission present at 1) 26 and 52 weeks, and 2) at 26, 52 and 78 weeks.
Following the methodology of the ACR/EULAR remission committee [1] good outcome
was defined as 1) DHAQ≤0 and HAQ consistently ≤0.5 and 2)
DSHS≤0, between 52 and 104 weeks. Logistic regression analyses
studied the potential of the above remission criteria to predict good outcome:
both at one point in time and according to the two defined periods of sustained
remission. Patients with missing data of remission criteria at ≥1 visits
(n=64) were excluded from these preliminary analyses.

Results: Hundred early RA patients (66% women, mean age 53
years) were included. Remission percentages at 26, 52, 78 and 104 weeks after
treatment are shown in
Figure 1.
The proportion of patients in sustained remission during 26-52 and 26-52-78
weeks respectively were: Boolean: 10%, 8%; RAPID: 13%, 12%; SDAI:19%, 16%;
CDAI: 19%, 17%; DAS44: 36%, 30%; and DAS28: 44%, 38%. Low, stable HAQ scores
were seen in 40% of the patients, and lack of radiological progression in 81%. All
remission criteria were predictive of low, stable HAQ scores between 52 and 104
weeks of follow-up, both at single points in time, as well as during periods of
sustained remission, except for sustained Boolean remission. Sustained
remission periods resulted in higher odds ratio’s for a low, stable HAQ
compared to remission at one point in time, except for DAS28 remission at 52
weeks. None of the criteria were predictive of lack of radiological progression,
neither at one point in time nor during periods of sustained remission, except
for RAPID remission at 52 weeks.

Conclusion: Early RA patients that reach
remission according to any of the available criteria during short or sustained
periods are likely to retain a good physical function in the subsequent months,
in which sustained periods of remission might be a stronger predictor than
remission at one point in time. In contrast, radiological damage progression
does not seem to be associated as strongly with (sustained) remission, probably
as a consequence of the low radiological damage progression overall.

Ref.: 1. Felson, Arthritis Rheum 2011; 2. Den Uyl, Ann Rheum
Dis 2014; 3. Ter Wee, Ann Rheum Dis 2015.

Figure 1: Remission percentages after 26, 52, 78 and 104
weeks of treatment in the COBRA-light trial (n=100)