A Cross-Sectional Hospital Based Study on Correlation between Serum Uric Acid Levels and Disease Activity in Recently Diagnosed Rheumatoid Arthritis in Chennai, Tamilnadu

Abstract

BACKGROUND Rheumatoid arthritis (RA) is an autoimmune chronic inflammatory disorder. Uric acid is a by-product of purine metabolism, associated with diseases such as gouty arthritis, hypertension and cardiovascular disease (CVD). The association between serum uric acid concentrations and inflammation in patients with RA has been controversial. Some case reports suggest coexistence of gout and RA. Uric acid crystals can induce robust inflammation causing joint destruction and fibrosis. The purpose of this study was to estimate the serum uric acid levels in subjects with recently diagnosed rheumatoid arthritis and to correlate with disease activity. METHODS This cross-sectional study was done on 55 recently diagnosed RA subjects [American college of Rheumatology (ACR) criteria 2010] attending the rheumatology out-patient department (OPD) of a tertiary care institute in Chennai, Tamil Nadu. After clinical examination, evaluation of disease activity score (DAS), serum uric acid and rheumatoid factor (RF) were done. Data was analysed using Statistical Package for Social Sciences (SPSS trial version 28). Descriptive and inferential analysis was done. Correlation between serum uric acid levels and DAS was the main outcome. RESULTS The mean age was 41.51 ± 11.7 years. 87.3 % were females. Majority (58.2 %) were aged between 31 to 50 years. The mean duration of symptoms was 4.78 months. The mean serum uric acid level was 4.99 ± 1.2 mg/dl with 95 % C.I. of 4.66 to 5.31. The mean DAS was 5.34 ± 0.96. 56 % had high disease activity while only 44 % had moderate disease activity. 44 % were RF positive. There was no significant difference in serum uric acid levels across groups based on RF positivity and DAS severity respectively. There was no statistically significant correlation serum uric acid levels and DAS (-0.024, P value = 0.861). CONCLUSIONS Mean serum uric acid levels were elevated in recently diagnosed rheumatoid arthritis. Serum uric acid levels have no association with DAS and RF positivity in rheumatoid arthritis. Further studies are needed to investigate the role of specific treatment of elevated uric acid levels in rheumatoid arthritis independent of rheumatoid arthritis treatment. KEYWORDS Rheumatoid Arthritis, Uric Acid, Rheumatoid Factor, Disease Activity Score (DAS), Correlation, Recently Diagnosed Rheumatoid Arthritis