Background: Achieving remission is one of the main goal in the management of patients (pts) with rheumatoid arthritis (RA). According to the literature, one of the determining predictor of the disease course is the serological variant of RA [1]. However, there are conflicting data in scientific publications concerning relationship between the presence/titre of antibodies to cyclic citrullinated peptide (ACCP) or rheumatoid factor (RF) and the frequency/rate of remission [1].

Objectives: To examine associations of ACCP- and RF-status with possibility and timing of clinical and radiological remission in Ukrainian pts with RA while taking the main non-biological disease modifying anti-rheumatic drugs (DMARD).

Methods: In enrolled pts RF titer was determined by the latex agglutination method (Humatex, Germany), reference values <20 IU/ml; ACCP level - by ELISA (IBL-Hamburg, Germany), the diagnostic limit of ACCP was ≥15U/ml, the maximum value ≥ 345U/ml. All pts received non-biological DMARD: methotrexate, leflunomide, sulfasalazine or its combination with hydroxychloroquine. At baseline and after 6, 12 and 24 months (mth) of treatment the disease activity and achievement of remission (by DAS28; Sharpe-van der Heide scale) in different subgroups of RA pts were analysed.

Results: 128 pts with RA were included in the study; the mean (SD) age was 54 (12.7) years and follow-up was for 2.0 (1.3) years. Most were women (72.4%), mean disease duration 18.4± 3.18 mth. ACCP-positive were 64.8% and RF - 57.1% pts. According to serological status at baseline, pts were stratified into four classes: ACCP+RF- (n=19), RF+ACCP- (n=9), dual positive (n=64) and dual negative (n=36). There were no significant differences between the analysed groups in age, sex, RA duration, disease activity, radiological changes and prescribed therapy (p>0.05).

During the 2-year follow-up, clinical remission was achieved in a total of 27 (21.1%) pts, including early remission (during first 6 mth) in 25 (19.5%). The percentage of pts in remission were 36.1, 33.3, 15.8, and 12.5 respectively for RF−/ACCP−, ACCP−/RF+, ACCP+/RF−, and ACCP+/RF+ (χ2 = 7.74, p<0.05 RF−/ACCP− vs ACCP+/RF+; χ2 = 4.55, p <0.05 ACCP−/RF+ vs ACCP+/RF+). The rate of remission (frequency of early remission in the structure of general remission) in four analysed groups did not differ significantly and was 75%, 66.6%, 66.6% and 84.6%, respectively. The ACCP titer in pts who achieved and didn’t achieve remission were respectively 240.8 ± 38.5 U / ml and 187.8 ± 13.7 U / ml, p>0.05. There also wasn’t difference between RF titer and the frequency of remission in these groups (257.9±233.8 IU / ml vs 293.2±257.3 IU / ml, p> 0.05). According to our data, there was no correlation between the level of RF / ACCP and the frequency of remission.

Radiological remission was achieved in 46.7% of ACCP-negative patients and only in 10.6% of ACCP-positive patients (p <0.01). The absence of RF in the blood was also associated with a more frequent achievement of radiological remission (in 34.2% of pts) compared with the RF-positive cohort of pts (in 15.4%, p <0.05). Double seronegative pts achieved remission three times more often (48.1% pts) than double seropositive (13.9%, p<0.01).

Conclusion: Our data suggest that the frequency of clinical remission, including early, is three times higher in patients with RA, negative for ACCP. The rate of clinical remission (ratio of early in the structure of the general) doesn’t depend on the serological variant of RA: about two thirds of pts in all analysed groups achieve remission in the first 6 mth of DMARD therapy. ACCP- and RF-titers in the onset of the disease don’t influence on the possibility of achieving clinical and radiological remission. Radiological remission is observed three times more often in seronegative (for ACCP or RF) pts. Double seropositivity has an additive effect on subsequent joint destruction.

REFERENCES:

[1]Yilmaz-Oner S. et al. Predictors and the optimal duration of sustained remission in rheumatoid arthritis. Clin Rheum. 2019;38(11):3033-3039.

Disclosure of Interests: None declared