ROLE OF URIC ACID IN CLINICAL MANIFESTATIONS OF ANKYLOSING SPONDYLITIS

Abstract

Prevalence of ankylosing spondylitis (AS) is about 0.2–0.8% and increasing during last decades in Russia. Coronary Heart Disease (CHD) plays an important role in mortality in patients with rheumatic diseases. AS mainly affects able-bodied age persons thus having a significant social and economic impact. There plenty of biomarkers of AS, including those for early diagnosis. Purpose. To study the level of uric acid (UA) in patients with AS and its role in development of AS. Materials and methods. A total of 72 medical charts of patients hospitalized at Smolensk Regional Rheumatological Center were evaluated, among them 73.6% were men and 26.4% – women. AS was diagnosed according to classification criteria. Lab tests were done in a central lab using standard methodology. All data collected for each patient was entered into an Excel spreadsheet and analyzed. Results. Average patients age was 49.6±12.4 years. BMI was 28.1±5.4 kg/m2. Arterial Hypertension (AH) and CHD was diagnosed in 44.4% of patients. Glomerular Filtration Rate (GFR) was 95.1±21.9 mL/min. UA concentration were equal to 301.3±94.3 mmol/L, total cholesterol (TC) – 5.0±1.0 mmol/L, CRP – 60.5±35.1 IU/L. A direct correlation between CRP and BMI was revealed (p<0.005). UA concentration in patients with AS and CHD was 347.3±73.9 mmol/L, while in patients with AS without CHD it was significantly lower: 261.8±77.4 mmol/L (p<0,001). UA concentration in patients with AS and HLA-B27(+) was 345.1±90.8 mmol/L, in patients with AS and HLA-B27(-) – 259.1±75.1 mmol/L (p<0,001). BASDAI in patients with AS was equal to 5.7±2.1. UA concentration in patients with mild to moderate AS was 255.4±77.7 mmol/L; severe AS – 343.4±75.3 mmol/L (p<0.001). Correlations between TC level and BASDAI (p<0.05) as well as between UA level and BASDAI (p<0.05) were revealed. Conclusion. In patients with AS increased level of UA supports inflammation activity, forces subjective symptoms of the disease (pain), correlates with disease activity and BASDAI. Hyperuricemia increases risk of CHD, worsens prognosis of AS. UA may be considered as a biomarker of disease activity and prognosis of AS, atherosclerosis and cardiovascular diseases