POS0279 GOUT PATIENTS ACHIEVING RECOMMENDED SERUM URIC ACID LEVELS OVER 5 YEARS OBTAIN LOW SCORES OF ULTRASOUND DEPOSITIONS; RESULTS FROM THE NOR-GOUT STUDY
Authors: H. B. Hammer, L. Karoliussen, L. Terslev, E. A. Haavardsholm, T. Uhlig
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Ultrasound (US) is sensitive for detecting monosodium urate (MSU) crystal depositions in gout, described as double contour (DC), tophi and aggregates. After persistent urate lowering treatment (ULT) we had at 1 year seen a significant decrease of the US depositions of MSU, and 85.3% of patients achieved the serum uric acid (sUA) target of &lt;360 µmol/L (i.e. &lt; 6 mg/dL) and 96.2% had &lt;400 µmol/L [1]. The patients were after the first year followed on ULT by their general practitioner and had follow-up study visits at year 2 and 5. <h3>Objectives:</h3> To explore whether the amount of US detected depositions at 2 and 5 years after initiation of ULT were related to achievement of the sUA target. <h3>Methods:</h3> Patients had clinical, laboratory and US assessments at baseline, 1, 2 and 5 years. The US examination (General Electric E9) included a semi-quantitative scoring of MSU depositions using the OMERACT scoring system [2] with bilateral examination of radiocarpal, metacarpophalangeal2, knee, ankle, and metatarsophalangeal1 joints as well as triceps, quadriceps, patellar (proximal and distal) and Achilles tendons and insertions. Total sum scores of US depositions (DC, tophi and aggregates, respectively) were calculated. Changes from baseline were explored by separate paired samples T-test for patients with sUA levels &lt; or &gt; 360 µmol/L. Differences between US depositions dependent on sUA was assessed by independent sample T-test. <h3>Results:</h3> 209 patients were included at baseline (mean (SD) age 56.4 (13.8) years, time since first flare (disease duration) 7.9 (7.7) years, 95.5% men). Mean sUA (µmol/L) during the study were 500 at baseline, 312 (n=184) at 1 year, 325 (n=173) at 2 years and 337 (n=161) at 5 years. At 2 years, 78.6% had sUA &lt;360 µmol/L and 89% &lt;400 µmol/L, and the corresponding percentages were 71.4 and 82.6 at 5 years. From 1 to 5 years, the sum scores of US (DC, tophi, and aggregates) decreased for patients with sUA &lt;360 µmol/L (p&lt;0.001) (Figure 1), but for patients having &gt;360 µmol/L at the visits, significant decreases were only found for tophi between year 1 and 2 (p=0.001) and for aggregates between year 2 and 5 (p=0.02). Patients with sUA &gt;360 µmol/L versus &lt;360 µmol/L at 2 years (n=37 vs 136) had higher scores of DC (p=0.02) and at 5 years (n= 46 vs 115) the patients with sUA &gt;360 µmol/L had higher scores of DC (p&lt;0.001), tophi (p=0.008) and aggregates (p=0.046). Figure 2 shows the US depositions at 5 years according to sUA levels, and highest scores were found in patients with sUA levels &gt; 400 µmol/L (p&lt;0.001). <h3>Conclusion:</h3> After treat-to-target ULT in the first year, 5-year reductions in US depositions were most favourable in patients who had a sUA levels &lt;360 µmol/L. Our findings support the recommendation to keep a low sUA level over time. <h3>REFERENCES:</h3> [1] Hammer HB et al. Ann Rheum Dis 2020. [2] Christiansen SN et al. Semin Arthritis Rheum 2021. <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> Hilde Berner Hammer AbbVie, Lilly, Novartis, UCB, Lars Karoliussen: None declared, Lene Terslev: None declared, Espen A. Haavardsholm Pfizer, AbbVie, Celgene, Novartis, Janssen, Gilead, Lilly, and UCB, Till Uhlig Novartis, SOBI.