Background Radiographic progression of joint damage in Rheumatoid Arthritis (RA) is associated with disease activity of RA. But the joint damage may progress in patients considered to be in clinical remission. It requires clarification whether the duration of remission of RA influence on joint damage progression.

Objectives The aim of this study was to compare radiographic progression of joint damage in patients (pts) with RA who had remission ≥ 6 months, pts with low disease activity and pts who had moderate disease activity.

Methods In the prospective study 127 pts with RA (according to ACR 1987) was performed analysis of development of new bone erosions in hands and feet in 2 years. All pts received controlled treatment with DMARDS according «treat-to-target» concept. The pts were divided into 3 groups: during 2 years 1 group - 31 pts were in remission ≥ 6 months, 2 group - 45 pts had low disease activity, 3 group - 51 pts had moderate disease activity. There were no differences in all baseline demographic and clinical characteristics (P>0,05) between 3 groups. The mean age was 42,4±15,8; 43,1±16,9; 43,5± 14,3 years; the median [25^th percentile-75^th percentile] duration of RA was 5,5 [2,5-13,5]; 15 [2,5-30,5]; 6 [2-39], the mean DAS28 was 5,5±1,0; 6,2±0,8; 6,1±1,7 respectively. Clinical remission, disease activity were defined according DAS28. Radiographic progression was assessed by the modified Sharp’s method. The statistical analysis was performed using parametric and nonparametric methods.

Results After 2 years the development of new bone erosions was in 11 (35%) pts of 1 group, in 34 (75%) pts of 2 group and in 41 (80%) pts of 3 group. (1 group vs 2 group P<0,01; 1 group vs 2 group P<0,01; 2 group vs 3 group P>0,05). The mean number of new erosions was: 0,7±1,2, median 0 [25^th percentile -75^th percentile] [0- 1] in pts of 1 group; 3,4±4,3 median 2 [0- 4] in pts of 2 group;13,3±12, median 10 [3,5-18,5] in pts of 3 group, P <0,001 between each group. 11 pts of 3th group had short-term remission (< 6 months), the mean number of new erosions was13,5±17,2, median 3,5 [2-24.5] and there was no difference from pts of 3th group without short-term remission (40 pts) - the mean number of new erosions was 13,2±11, median 10 [4,5-18] P>0,05.

Conclusions Thus, the remission ≥ 6 months is correlated with development significantly less numbers of new bone erosions, than persistent low and particularly, moderate activity of RA. Duration of remission < 6 months not inhibit progression of joint damage.

Disclosure of Interest None Declared