P130 The relationship between antinuclear antibodies and erosive disease in patients with rheumatoid arthritis

Abstract

Abstract Background/Aims The effects of antinuclear antibodies (ANA) in rheumatoid arthritis (RA) are not fully characterised. Studies investigating the effect of ANA on disease activity in RA have yielded mixed results. The presence of ANA has been correlated with higher levels of CRP and joint inflammation in RA. Evidence suggests that ANA positivity at baseline may predict poor response to both traditional disease modifying agents and biologic therapy. ANA may also be associated with higher incidences of ocular disease, Felty’s syndrome, vasculitis and subjective pain in RA patients. On the other hand, other studies showed a lack of correlation between ANA status and joint inflammation in RA. Our study investigates the relationship between ANA positivity and joint erosions in rheumatoid patients. Methods This is a cross-sectional study of patients attending the early arthritis clinic at Northwick Park Hospital in London over a five year period (2014-2019). A total of 631 patients were identified of whom 261 had RA. We collected data on the age, gender, ANA positivity, the presence of anti-CCP (anti cyclic-citrullinated peptide) antibodies and rheumatoid factor (RF) at presentation as well as the presence of erosive disease on radiological reports of hand X-rays. Positive ANA was defined as having a titre of 1:80 or greater. Patients with missing ANA result or hand X-ray reports were excluded, leaving 228 patients. Two-tailed Chi-square tests for categorical data and two-tailed student’s t-tests for continuous data were performed to determine the statistical significance of comparisons made between the ANA positive and negative groups. Results Of the 228 patients, 49 (21.5%) were male and 179 (78.5%) were female. The mean age was 58 years. 84 (36.8%) patients were ANA positive (group 1) and 144 (63.2%) were ANA negative (group 2). In group 1, 23/84 (27.4%) patients had erosive disease. In group 2, erosions were found in 25/144 patients (17.4%). This difference was not statistically significant (p = 0.073). The number of patients who were RF positive in groups 1 and 2 were 79.5% and 73.6% respectively (p = 0.317); 75/84 (89.3%) patients in group 1 and 113/143 (79.0%) in group 2 were anti-CCP antibody positive (p = 0.048). The means of the age of patients were 53 and 62 years in group 1 and group 2 respectively (p < 0.0001); the ANA positive group was significantly younger. The male:female ratio was 13:71 in group 1 and 36:108 in group 2 (p = 0.091). Conclusion Our study showed no significant association between ANA status and erosive disease in RA, although a greater proportion of patients had erosions in the ANA positive group. Larger observational studies may better study this relationship. Disclosure T. Guruparan: None. M. Hutchinson: None. R. Hayward: None. H. Penn: None. P. Kalia: None.