AB0596 ASSESSING THE ASSOCIATION BETWEEN ACCP ANTIBODY STATUS AND THE TIME-TO-REMISSION AMONG RHEUMATOID ARTHRITIS PATIENTS TREATED WITH CONVENTIONAL DMARDs

Background: Rheumatoid arthritis (RA) is a systemic inflammatory disorder primarily involving the synovial joints of the body. It affects up to 0.24% of the global population, and untreated disease invariably leads to permanent joint damage, compromised quality of life, and death from extra-articular disease. Whereas anti-cyclic citrullinated peptide (ACCP) antibody positivity puts RA patients at a greater risk of disease severity, whether it affects response to conventional disease-modifying antirheumatic drugs (DMARDs) is not clearly known. Objectives: This study aims to compare the time-to-remission between ACCP antibody-positive and negative rheumatoid arthritis patients treated with conventional DMARDs. Methods: A multicenter institution-based retrospective follow-up study was conducted from September 2019 to August 2023 at one public and four private hospitals in Addis Ababa, Ethiopia. Patients with any one of the following were excluded: (1) previous exposure to conventional DMARDs; (2) no baseline erythrocyte sedimentation rate (ESR), tender joint count (TJC), swollen joint count (SJC), or ACCP antibody; (3) remission at baseline; and (4) no follow-up visit. Eligible patients were categorized into two groups based on their ACCP antibody status: ACCP negative and ACCP positive, and were then retrospectively followed until any one of the following occurred: (1) remission; (2) 12 months since the start of DMARD; (3) medication discontinuation; (4) loss to follow-up; or (5) end of study period (August 31, 2023). Remission was defined as a disease activity score in 28 joints (DAS-28) score of less than 2.6. The Kaplan-Meier survival function was used to compare the survival experiences of the two groups. Adjusted hazard ratio (AHR) was calculated using the Cox regression model to control for potential confounders including age, sex, duration of illness, rheumatoid factor (RF) status, baseline disease severity (TJC, SJC, ESR, C-reactive protein [CRP], and DAS-28), the presence of comorbidities, and the treatment regimens used. Odds ratios (ORs) were used to determine factors associated with ACCP positivity and variables with less than 0.25 p-values in the binary logistic regression model were used for multiple logistic regression model. Results: A total of 1,429 RA patients were screened, and 214 patients (153 ACCP positive and 61 ACCP negative) were found to be eligible for the study and included in the final analysis. The mean (standard deviation) age at diagnosis was 46.9 (14.1) years, and 175 (81.8%) were female. The mean duration of symptoms was 33.2 ± 41.8 months, and the mean duration of follow-up was 5 months. Remission occurred in 60.1% of ACCP-positive and 45.9% of ACCP-negative patients (AHR, 2.16; 95% confidence interval [CI], 1.25 to 3.72; P = 0.006). Female sex (adjusted odds ratios [AOR], 2.79; 95% CI, 1.15 to 6.77; P = 0.023), RF positivity (AOR, 5.77; 95% CI, 2.82–11.77; P<0.001), and having no comorbidities (AOR, 0.46; 95% CI, 0.22–0.97; P = 0.04) were significantly associated with ACCP positivity. Conclusion: ACCP antibody positivity is significantly associated with a faster time-to-remission among RA patients treated with conventional DMARDs. Female sex, RF positivity, and having no comorbidities are independently associated with ACCP antibody positivity. REFERENCES: NIL. Acknowledgements: NIL. Disclosure of Interests: None declared.